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Systematic review| Volume 123, ISSUE 3, P346-354, June 2017

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Comparison of particle beam therapy and stereotactic body radiotherapy for early stage non-small cell lung cancer: A systematic review and hypothesis-generating meta-analysis

  • Alexander Chi
    Correspondence
    Corresponding authors at: Department of Radiation Oncology, Shanghai Proton and Heavy Ion Center, Shanghai, China (A. Chi). Department of Biostatistics, School of Public Health, West Virginia University, Morgantown, WV, USA (S. Wen).
    Affiliations
    Department of Radiation Oncology, Shanghai Proton and Heavy Ion Center, China
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  • Haiquan Chen
    Affiliations
    Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, China
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  • Sijin Wen
    Correspondence
    Corresponding authors at: Department of Radiation Oncology, Shanghai Proton and Heavy Ion Center, Shanghai, China (A. Chi). Department of Biostatistics, School of Public Health, West Virginia University, Morgantown, WV, USA (S. Wen).
    Affiliations
    Department of Biostatistics, School of Public Health, West Virginia University, Morgantown, USA
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  • Haijuan Yan
    Affiliations
    Department of Biostatistics, School of Public Health, West Virginia University, Morgantown, USA
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  • Zhongxing Liao
    Affiliations
    Department of Radiation Oncology, MD Anderson Cancer Center, Houston, USA
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Published:May 22, 2017DOI:https://doi.org/10.1016/j.radonc.2017.05.007
Comparison of particle beam therapy and stereotactic body radiotherapy for early stage non-small cell lung cancer: A systematic review and hypothesis-generating meta-analysis
Previous ArticleFirst clinical investigation of a 4D maximum likelihood reconstruction for 4D PET-based treatment verification in ion beam therapy
Next ArticleVerifying tumor position during stereotactic body radiation therapy delivery using (limited-arc) cone beam computed tomography imaging

      Abstract

      Purpose

      To assess hypo-fractionated particle beam therapy (PBT)’s efficacy relative to that of photon stereotactic body radiotherapy (SBRT) for early stage (ES) non-small cell lung cancer (NSCLC).

      Methods

      Eligible studies were identified through extensive searches of the PubMed, Medline, Google-scholar, and Cochrane library databases from 2000 to 2016. Original English publications of ES NSCLC were included. A meta-analysis was performed to compare the survival outcome, toxicity profile, and patterns of failure following each treatment.

      Results

      72 SBRT studies and 9 hypo-fractionated PBT studies (mostly single-arm) were included. PBT was associated with improved overall survival (OS; p = 0.005) and progression-free survival (PFS; p = 0.01) in the univariate meta-analysis. The OS benefit did not reach its statistical significance after inclusion of operability into the final multivariate meta-analysis (p = 0.11); while the 3-year local control (LC) still favored PBT (p = 0.03).

      Conclusion

      Although hypo-fractionated PBT may lead to additional clinical benefit when compared with photon SBRT, no statistically significant survival benefit from PBT over SBRT was observed in the treatment of ES NSCLC in this hypothesis-generating meta-analysis after adjusting for potential confounding variables.

      Keywords

      Lung cancer is the most common cancer and the leading cause of cancer-related deaths worldwide [

      Worldwide cancer statistics. Cancer Research UK, www.cancerresearchuk.org/health-professional/cancer-statistics/worldwide-cancer, accessed in July, 2016.

      ]. Non-small cell lung cancer (NSCLC), which represents the majority of lung cancer diagnosed, often presents in late stages. Low-dose (LD) CT screening of patients who are at a high risk to develop lung cancer has been associated with a decrease in lung cancer related mortality and a high specificity in selected studies [
      • The National Lung Screening Trial Research Team
      Reduced lung-cancer mortality with low-dose computed tomographic screening.
      N Engl J Med. 2011; 365: 395-409
      ,
      • Aberle D.R.
      • Abtin F.
      • Brown K.
      Computed tomography screening for lung cancer: has it finally arrived? Implications of the national lung screening trial.
      J Clin Oncol. 2013; 31: 1002-1008
      ,
      • van Klaveren R.J.
      • Oudkerk M.
      • Prokop M.
      • Scholten E.T.
      • Nackaerts K.
      • Vernhout R.
      • et al.
      Management of lung nodules detected by volume CT scanning.
      N Engl J Med. 2009; 361: 2221-2229
      ,
      • Walter J.E.
      • Heuvelmans M.A.
      • de Jong P.A.
      • Vliegenthart R.
      • van Ooijen P.M.A.
      • Peters R.B.
      • et al.
      Occurrence and lung cancer probability of new solid nodules at incidence screening with low-dose CT: analysis of data from the randomised, controlled NELSON trial.
      Lancet Oncol. 2016; 17: 907-916
      ]. Its clinical adaptation in the high-risk population has caused an increase in the number of patients diagnosed with stage I NSCLC in recent years [
      • The National Lung Screening Trial Research Team
      Reduced lung-cancer mortality with low-dose computed tomographic screening.
      N Engl J Med. 2011; 365: 395-409
      ,
      • Aberle D.R.
      • Abtin F.
      • Brown K.
      Computed tomography screening for lung cancer: has it finally arrived? Implications of the national lung screening trial.
      J Clin Oncol. 2013; 31: 1002-1008
      ,
      • van Klaveren R.J.
      • Oudkerk M.
      • Prokop M.
      • Scholten E.T.
      • Nackaerts K.
      • Vernhout R.
      • et al.
      Management of lung nodules detected by volume CT scanning.
      N Engl J Med. 2009; 361: 2221-2229
      ,
      • Walter J.E.
      • Heuvelmans M.A.
      • de Jong P.A.
      • Vliegenthart R.
      • van Ooijen P.M.A.
      • Peters R.B.
      • et al.
      Occurrence and lung cancer probability of new solid nodules at incidence screening with low-dose CT: analysis of data from the randomised, controlled NELSON trial.
      Lancet Oncol. 2016; 17: 907-916
      ,
      • Yip R.
      • Henschke C.I.
      • Yankelevitz D.F.
      • Boffetta P.
      • Smith J.P.
      The impact of the regimen of screening on lung cancer cure: a comparison of I-ELCAP and NLST.
      Eur J Cancer Prev. 2015; 24: 201-208
      ,
      • Gould M.K.
      • Donington J.
      • Lynch W.R.
      • Mazzone P.J.
      • Midthun D.E.
      • Naidich D.P.
      • et al.
      Evaluation of individuals with pulmonary nodules: when is it lung cancer? Diagnosis and management of lung cancer, 3rd ed: American college of chest physicians evidence-based clinical practice guidelines.
      Chest. 2013; 143: e93S-120S
      ,

      Callister MEJ, Baldwin DR, Akram AR, Barnard S, Cane P, Draffan J, et al. British thoracic society guidelines for the investigation and management of pulmonary nodules. Thorax 2015; 70 Suppl 2: ii1 - ii54.

      ]. Early-stage (ES) NSCLC has traditionally been treated with surgery in operable patients. As an alternative, excellent clinical outcome following high dose irradiation delivered with stereotactic body radiotherapy (SBRT) has been observed in inoperable patients with ES, lymph node negative, NSCLC [
      • Chi A.
      • Liao Z.
      • Nguyen N.P.
      • Xu J.
      • Stea B.
      • Komaki R.
      Systemic review of the patterns of failure following stereotactic body radiation therapy in early-stage non-small-cell lung cancer: clinical implications.
      Radiother Oncol. 2010; 94: 1-11
      ]. This treatment technique is also known as stereotactic ablative radiotherapy (SABR). An ablative dose is delivered to the tumor with SBRT over one to two weeks. This is administered under daily image guidance to ensure accurate tumor localization and maximal sparing of the surrounding normal tissue. SBRT has been quickly adopted into clinical practice worldwide. Its efficacy was found to be potentially comparable to surgery in selected patients [
      • Onishi H.
      • Shirato H.
      • Nagata Y.
      • Hiraoka M.
      • Fujino M.
      • Gomi K.
      • et al.
      Stereotactic body radiotherapy (SBRT) for operable stage I non-small-cell lung cancer: can SBRT be comparable to surgery?.
      Int J Radiat Oncol Biol Phys. 2011; 81: 1352-1358
      ,
      • Verstegen N.E.
      • Oosterhuis J.W.A.
      • Palma D.A.
      • Rodrigues G.
      • Lagerwaard F.J.
      • van der Elst A.
      • et al.
      Stage I-II non-small-cell lung cancer treated using either stereotactic ablative radiotherapy (SABR) or lobectomy by video-assisted thoracoscopic surgery (VATS): outcomes of a propensity score-matched analysis.
      Ann Oncol. 2013; 24: 1543-1548
      ,
      • Chang J.
      • Senan S.
      • Paul M.A.
      • Mehran R.J.
      • Louie A.V.
      • Balter P.
      • et al.
      Stereotactic ablative radiotherapy versus lobectomy for operable stage I non-small-cell lung cancer: a pooled analysis of two randomised trials.
      Lancet Oncol. 2015; 16: 630-637
      ]. As more patients are diagnosed with ES NSCLC through LD-CT screening, high dose irradiation with precision, such as SBRT, may become increasingly considered for this disease. However, SBRT is not without limitations. For example, its application is still limited by tumor location with severe toxicity more frequently encountered in patients with centrally located lesions [
      • Chi A.
      • Nguyen N.P.
      • Komaki R.
      The potential role of respiratory motion management and image guidance in the reduction of severe toxicities following stereotactic ablative radiation therapy for patients with centrally located early stage non-small cell lung cancer or lung metastases.
      Front Oncol. 2014; 4: 151
      ]. This problem may be mitigated by increasing dose fractionation because of photons’ physical characteristics. However, tumor proximity to critical thoracic structures still prohibits the utility of SBRT in many patients due to the risk of severe toxicity associated high doses to these structures if a therapeutic dose were to be delivered. Also, photon SBRT poses great challenges in the delivery of subsequent high dose re-irradiation for loco-regional recurrence in many patients as a result of the high dose already delivered to critical thoracic organs during the first course of treatment. As an emerging technology, particle beam (proton and heavy ions, such as carbon ions) therapy (PBT) possesses unique physical properties that allow the irradiation of tumors at any depth within the body with a very sharp dose gradient at the distal edge of the tumor target [

      Linz U. Physical and biological rationale for using ions in therapy, Ion Beam Therapy: Fundamentals, Technology, Clinical Applications. Linz U, Ed., Springer, Heidelberg, Dordrecht, London, New York, 2012; 45–59.

      ]. This may greatly decrease the dose to the healthy tissues surrounding the tumor in the setting of high dose irradiation in comparison with photon SBRT. Heavy ions, such as carbon ions, also have a biological advantage over photons due to the higher probability of tumor DNA damage associated with their high linear energy transfer (LET). In recent years, more facilities have been delivering PBT for the treatment of ES NSCLC. In this comprehensive critical review and hypothesis-generating meta-analysis, we aim to analyze and compare the efficacy of hypo-fractionated PBT, which is delivered with highly-advanced technology, with that of photon SBRT, a relatively more mature technique that has been in clinical use for over a decade, in the treatment of ES NSCLC.

      Methods

      Search strategy and selection criteria

      A systematic search was conducted in PubMed, Medline, Google-scholar, and the Cochrane library for studies published between January 2000, and June 2016. The subject heading “non-small cell lung cancer/ carcinoma” was combined with the following terms: “early stage”, “stage I”, “T1”, “T2”, “stereotactic body radiation therapy”, “stereotactic body radiotherapy”, “stereotactic ablative radiotherapy”, “SBRT”, “SABR”, “hypo-fractionated radiotherapy”, “particle beam therapy”, “proton therapy”, “carbon ion therapy”, “carbon ion radiotherapy”, and “carbon ion radiation therapy”. Relevant articles, abstracts, and review articles were selected and reviewed. The references from these sources were searched for additional studies. Proceedings of the annual meetings of the American Society of Radiation Oncology, American Society of Clinical Oncology, and the European Society of Radiotherapy & Oncology from 2000 onward were manually searched for relevant abstracts, then a search for a fully published manuscript was done. The Physician Data Query (PDQ) clinical trials database was searched for relevant ongoing trials. The last search was conducted on July 1, 2016.
      Only studies published in English in peer-reviewed journals were included. Eligible studies include prospective or retrospective studies of SBRT or SABR, and hypo-fractionated PBT, such as proton therapy and carbon ion therapy, as definitive treatment for ES NSCLC (T1, T2, or T3, N0, M0 per the 7th edition of cancer staging by the American Joint Committee on Cancer (AJCC)). Only the latest study with the most comprehensive report of clinical outcome and treatment toxicity was selected when multiple studies on the same patient population from the same institution were found. Multiple reports from the same institution were included if the patient populations were from different time periods, treated differently, or the reports on the same patient population complement each other in data reporting. The search was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines [
      • Liberati A.
      • Altman D.G.
      • Tetzlaff J.
      • Mulrow C.
      • Gøtzsche P.C.
      • Ioannidis J.P.A.
      • et al.
      The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration.
      PLos Med. 2009; 6: e1000100
      ], and a structured literature search schema was followed (Suppl. Fig. 1).

      Data extraction

      Studies were extracted independently by two investigators. All relevant characteristics, such as first author, publication year, country, study design, age, sample size, tumor stage, follow up period, clinical outcome (including patterns of failure and survival data), and treatment related toxicity, were collected. For each study, the radiation dose fractionation regimen used was recorded. For survival endpoints, 1, 2, 3, 4, and 5 year data were collected when available. Local control was defined as freedom from any local progression. Survival data were extracted from Kaplan–Meier survival curves when survival rates were not explicitly stated. The biologically effective dose (BED10) for tumor was calculated based on the linear-quadratic equation: BED10 = D [1 + d/(α/β)], where D and d represents the total and fractional radiation dose. α/β for tumor equals to 10 Gy−1.

      Statistical analysis

      The clinical outcomes of interest include local control, overall survival, progression-free survival at 1, 2, 3, 4 and 5 years and treatment related toxicity. Descriptive statistics and exploratory data analysis were used to summarize the data, including summary tables, box-plots, proportions, mean, median, and range. Summary estimates of event proportion, and relative risk (RR) were estimated from the available data at each time point, using the weighted regression model, and the random-effects model/mixed-effects model (Supplementary material) [
      • Seber G.A.F.
      Linear regression analysis.
      Wiley, New York1977
      ,
      • Arends L.R.
      • Hunink M.G.M.
      • Stijnen T.
      Meta-analysis of summary survival data.
      Statist Med. 2008; 27: 4381-4396
      ]. Continuous data such as tumor size and median follow-up were evaluated using weighted mean with 95% confidence intervals (CI). Dichotomous data such as adverse effects were summarized using proportion and relative risk with 95% CI. Forest plots were used to evaluate relative risk on local control and 3-year survival between two conditions such as T1 vs. T2 groups, where 95% confidence intervals for RR in each study were represented by horizontal lines and the point estimate by a square. The height of each square is inversely proportional to the standard error of the estimate. The summary RR is represented by a diamond with horizontal limits at the 95% confidence interval and width inversely proportional to its standard error. A multivariate meta-regression model was used to assess treatment effect, including covariates, such as patient/tumor characteristics, and treatment modality, to account for population heterogeneity. Data analysis was performed using the meta-analysis package “meta” [
      • Schwarzer G.
      Meta: an R package for meta-analysis.
      R News. 2007; 7: 40-45
      https://cran.r-project.org/doc/Rnews/Rnews_2007-3.pdf
      ,
      • Schwarzer G.
      • Carpenter J.R.
      • Rücker G.
      Meta-analysis with R (Use-R!).
      Springer International Publishing, Switzerland2015
      ] and statistical software R (version 3.31, R Foundation, Vienna, Austria).

      Results

      Study selection and characteristics

      The study selection process is shown in Suppl. Fig. 1. Among 501 relevant publications on SBRT and 113 relevant publications on PBT, 205 full text articles for SBRT and 19 full text articles for hypo-fractionated PBT (proton and carbon ion therapy) were assessed for eligibility. Of these, 72 studies on photon SBRT and 9 studies on PBT for ES NSCLC were selected [
      • Onishi H.
      • Shirato H.
      • Nagata Y.
      • Hiraoka M.
      • Fujino M.
      • Gomi K.
      • et al.
      Stereotactic body radiotherapy (SBRT) for operable stage I non-small-cell lung cancer: can SBRT be comparable to surgery?.
      Int J Radiat Oncol Biol Phys. 2011; 81: 1352-1358
      ,
      • Chang J.
      • Senan S.
      • Paul M.A.
      • Mehran R.J.
      • Louie A.V.
      • Balter P.
      • et al.
      Stereotactic ablative radiotherapy versus lobectomy for operable stage I non-small-cell lung cancer: a pooled analysis of two randomised trials.
      Lancet Oncol. 2015; 16: 630-637
      ,
      • Timmerman R.
      • Paulus R.
      • Galvin J.
      • Michalski J.
      • Straube W.
      • Bradley J.
      • et al.
      Stereotactic body radiation therapy for inoperable early stage lung cancer.
      JAMA. 2010; 303: 1070-1076
      ,
      • Timmerman R.D.
      • Hu C.
      • Michalski J.
      • Straube W.
      • Galvin J.
      • Johnstone D.
      • et al.
      Long-term results of RTOG 0236: a phase II trial of stereotactic body radiation therapy (SBRT) in the treatment of patients with medically inoperable stage I non-small cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2014; 90: S30
      ,
      • Videtic G.M.
      • Hu C.
      • Singh A.K.
      • Chang J.Y.
      • Parker W.
      • Olivier K.R.
      • et al.
      A randomized phase 2 study comparing 2 stereotactic body radiation therapy schedules for medically inoperable patients with stage I peripheral non-small cell lung cancer: NRG Oncology RTOG 0915 (NCCTG N0927).
      Int J Radiat Oncol Biol Phys. 2015; 93: 757-764
      ,
      • Fakiris A.J.
      • McGarry R.C.
      • Yiannoutsos C.T.
      • Papiez L.
      • Williams M.
      • Henderson M.A.
      • et al.
      Stereotactic body radiation therapy for early-stage non-small-cell lung carcinoma: four-year results of a prospective phase II study.
      Int J Radiat Oncol Biol Phys. 2009; 75: 677-682
      ,
      • Baumann P.
      • Nyman J.
      • Hoyer M.
      • Wennberg B.
      • Gagliardi G.
      • Lax I.
      • et al.
      Outcome in a prospective phase II trial of medically inoperable stage I non-small-cell lung cancer patients treated with stereotactic body radiotherapy.
      J Clin Oncol. 2009; 27: 3290-3296
      ,
      • Lindberg K.
      • Nyman J.
      • Källskog V.R.
      • Hoyer M.
      • Lund J.Ǻ.
      • Lax I.
      • et al.
      Long-term results of a prospective phase II trial of medically inoperable stage I NSCLC treated with SBRT – the Nordic experience.
      Acta Oncol. 2015; 54: 1096-1104
      ,
      • Navarro-Martin A.
      • Aso S.
      • Cacicedo J.
      • Arnaiz M.
      • Navarro V.
      • Rosales S.
      • et al.
      Phase II trial of SBRT for stage I NSCLC: survival, local control, and lung function at 36 months.
      J Thorac Oncol. 2016; (In press)
      ,
      • Bral S.
      • Gevaert T.
      • Linthout N.
      • Versmessen H.
      • Collen C.
      • Engels B.
      • et al.
      Prospective, risk-adapted strategy of stereotactic body radiotherapy for early-stage non-small-cell lung cancer: results of a phase II trial.
      Int J Radiat Oncol Biol Phys. 2011; 80: 1343-1349
      ,
      • Ricardi U.
      • Filippi A.R.
      • Guarneri A.
      • Giglioli F.R.
      • Ciammella P.
      • Franco P.
      • et al.
      Stereotactic body radiation therapy for early stage non-small cell lung cancer: results of a prospective trial.
      Lung Cancer. 2010; 68: 72-77
      ,
      • Nagata Y.
      • Hiraoka M.
      • Shibata T.
      • Onishi H.
      • Kokubo M.
      • Karasawa K.
      • et al.
      Prospective trial of stereotactic body radiation therapy for both operable and inoperable T1N0M0 non-small cell lung cancer: Japan Clinical Oncology Group Study JCOG0403.
      Int J Radiat Oncol Biol Phys. 2015; 93: 989-996
      ,
      • Koto M.
      • Takai Y.
      • Ogawa Y.
      • Matsushita H.
      • Takeda K.
      • Takahashi C.
      • et al.
      A phase II study on stereotactic body radiotherapy for stage I non-small cell lung cancer.
      Radiother Oncol. 2007; 85: 429-434
      ,
      • Onishi H.
      • Kuriyama K.
      • Komiyama T.
      • Tanaka S.
      • Sano N.
      • Marino K.
      • et al.
      Clinical outcomes of stereotactic radiotherapy for stage I non-small cell lung cancer using a novel irradiation technique: patient self-controlled breath-hold and beam switching using a combination of linear accelerator and CT scanner.
      Lung Cancer. 2004; 45: 45-55
      ,
      • Onimaru R.
      • Shirato H.
      • Shibata T.
      • Hiraoka M.
      • Ishikura S.
      • Karasawa K.
      • et al.
      Phase I study of stereotactic body radiation therapy for peripheral T2N0M0 non-small cell lung cancer with PTV∗∗ 100 cc using a continual reassessment method (JCOG0702).
      Radiother Oncol. 2015; 116: 276-280
      ,
      • Chiang A.
      • Thibault I.
      • Warner A.
      • Rodrigues G.
      • Palma D.
      • Soliman H.
      • et al.
      A comparison between accelerated hypofractionation and stereotactic ablative radiotherapy (SABR) for early-stage non-small cell lung cancer (NSCLC): results of a propensity score-matched analysis.
      Radiother Oncol. 2016; 118: 478-484
      ,
      • Taremi M.
      • Hope A.
      • Dahele M.
      • Pearson S.
      • Fung S.
      • Purdie T.
      • et al.
      Stereotactic body radiotherapy for medically inoperable lung cancer: prospective, single-center study of 108 consecutive patients.
      Int J Radiat Oncol Biol Phys. 2012; 82: 967-973
      ,
      • Mak R.H.
      • Hermann G.
      • Lewis J.H.
      • Aerts H.J.W.L.
      • Baldini E.H.
      • Chen A.B.
      • et al.
      Outcomes by tumor histology and KRAS mutation status after lung stereotactic body radiation therapy for early-stage non-small-cell lung cancer.
      Clin Lung Cancer. 2015; 16: 24-32
      ,
      • Ebright M.I.
      • Russo G.A.
      • Gupta A.
      • Subramaniam R.M.
      • Fernando H.C.
      • Kachnic L.A.
      Positron emission tomography combined with diagnostic chest computed tomography enhances detection of regional recurrence after stereotactic body radiation therapy for early stage non-small cell lung cancer.
      J Thorac Cardiovasc Surg. 2013; 145: 709-715
      ,
      • Park H.S.
      • Harder E.M.
      • Mancini B.R.
      • Decker R.H.
      Central versus peripheral tumor location: influence on survival, local control, and toxicity following stereotactic body radiotherapy for primary non-small-cell lung cancer.
      J Thorac Oncol. 2015; 10: 832-837
      ,
      • Spratt D.E.
      • Wu A.J.
      • Adeseye V.
      • Din S.U.
      • Shaikh F.
      • Woo K.M.
      • et al.
      Recurrence patterns and second primary lung cancers after stereotactic body radiation therapy for early-stage non-small-cell lung cancer: implications for surveillance.
      Clin Lung Cancer. 2015; 17: 177-183
      ,
      • Parashar B.
      • Port J.
      • Arora S.
      • Christos P.
      • Trichter S.
      • Nori D.
      • et al.
      Analysis of stereotactic body radiation vs. wedge resection vs. wedge resection plus cesium-131 brachytherapy in early stage lung cancer.
      Brachytherapy. 2015; 14: 648-654
      ,
      • Kelley K.D.
      • Benninghoff D.L.
      • Stein J.S.
      • Li J.Z.
      • Byrnes R.T.
      • Potters L.
      • et al.
      Medically inoperable peripheral lung cancer treated with stereotactic body radiation therapy.
      Radiat Oncol. 2015; 10: 120
      ,
      • Vu C.C.
      • Matthews R.
      • Kim B.
      • Franceschi D.
      • Bilfinger T.V.
      • Moore W.H.
      Prognostic value of metabolic tumor volume and total lesion glycolysis from 18F-FDG PET/CT in patients undergoing stereotactic body radiation therapy for stage I non-small-cell lung cancer.
      Nucl Med Commun. 2013; 34: 959-963
      ,
      • Horne Z.D.
      • Clump D.A.
      • Vargo J.A.
      • Shah S.
      • Beriwal S.
      • Burton S.A.
      • et al.
      Pretreatment SUVmax predicts progression-free survival in early-stage non-small cell lung cancer treated with stereotactic body radiation therapy.
      Radiat Oncol. 2014; 9: 41
      ,
      • Vahdat S.
      • Oermann E.K.
      • Collins S.P.
      • Yu X.
      • Abedalthagafi M.
      • DeBrito P.
      • et al.
      Cyberknife radiosurgery for inoperable stage IA non-small cell lung cancer: 18F-fluorodeoxyglucose positron emission tomography/computed tomography serial tumor response assessment.
      J Hem Oncol. 2010; 3: 6
      ,
      • Dunlap N.E.
      • Larner J.M.
      • Read P.W.
      • Kozower B.D.
      • Lau C.L.
      • Sheng K.
      • et al.
      Size matters: a comparison of T1 and T2 peripheral non-small-cell lung cnacers treated with stereotactic body radiation therapy (SBRT).
      J Thorac Cardiovasc Surg. 2010; 140: 583-589
      ,
      • Brown W.T.
      • Wu X.
      • Fayad F.
      • Fowler J.F.
      • García S.
      • Monterroso M.I.
      • et al.
      Application of robotic stereotactic radiotherapy to peripheral stage I non-small cell lung cancer with curative intent.
      Clin Oncol. 2009; 21: 623-631
      ,
      • Grills I.S.
      • Hope A.J.
      • Guckenberger M.
      • Kestin L.L.
      • Werner-Wasik M.
      • Yan D.
      • et al.
      A collaborative analysis of stereotactic lung radiotherapy outcomes for early-stage non-small-cell lung cancer using daily online cone-beam computed tomography image-guided radiotherapy.
      J Thorac Oncol. 2012; 7: 1382-1393
      ,
      • Videtic G.M.
      • Stephans K.L.
      • Woody N.M.
      • Reddy C.A.
      • Zhuang T.
      • Magnelli A.
      • et al.
      30 Gy or 34 Gy? Comparing 2 single-fraction SBRT dose schedules for stage I medically inoperable non-small cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2014; 90: 203-208
      ,
      • Burdick M.J.
      • Stephans K.L.
      • Reddy C.A.
      • Djemil T.
      • Srinivas S.M.
      • Videtic G.M.
      Maximum standardized uptake value from staging FDG-PET/CT does not predict treatment outcome for early-stage non-small-cell lung cancer treated with stereotactic body radiotherapy.
      Int J Radiat Oncol Biol Phys. 2010; 78: 1033-1039
      ,
      • Fischer-Valuck B.W.
      • Boggs H.
      • Katz S.
      • Durci M.
      • Acharya S.
      • Rosen L.R.
      Comparison of stereotactic body radiation therapy for biopsy-proven versus radiographically diagnosed early-stage non-small lung cancer: a single-institution experience.
      Tumori. 2015; 10: 287-293
      ,
      • Zhang X.
      • Liu H.
      • Balter P.
      • Allen P.K.
      • Komaki R.
      • Pan T.
      • et al.
      Positron emission tomography for assessing local failure after stereotactic body radiotherapy for non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2012; 83: 1558-1565
      ,
      • Shultz D.B.
      • Trakul N.
      • Abelson J.A.
      • Murphy J.D.
      • Maxim P.G.
      • Le Q.T.
      • et al.
      Imaging features associated with disease progression after stereotactic ablative radiotherapy for stage I non-small-cell lung cancer.
      Clin Lung Cancer. 2014; 15: 294-301
      ,
      • Trakul N.
      • Chang C.N.
      • Harris J.
      • Chapman C.
      • Rao A.
      • Shen J.
      • et al.
      Tumor volume-adpated dosing in stereotactic ablative radiotherapy of lung tumors.
      Int J Radiat Oncol Biol Phys. 2012; 84: 231-237
      ,
      • Shaverdian N.
      • Veruttipong D.
      • Wang J.
      • Schaue D.
      • Kupelian P.
      • Lee P.
      Pretreatment immune parameters predict for overall survival and toxicity in early-stage non-small-cell lung cancer patients treated with stereotactic body radiation therapy.
      Clin Lung Cancer. 2016; 17: 39-46
      ,
      • Nath S.K.
      • Sandhu A.P.
      • Kim D.
      • Bharne A.
      • Nobiensky P.D.
      • Lawson J.D.
      • et al.
      Locoregional and distant failure following image-guided stereotactic body radiation for early-stage primary lung cancer.
      Radiother Oncol. 2011; 99: 12-17
      ,
      • Olsen J.R.
      • Robinson C.G.
      • El Naqa I.
      • Creach K.M.
      • Drzymala R.E.
      • Parikh P.J.
      • et al.
      Dose-response for stereotactic body radiotherapy in early-stage non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2011; 81: e299-303
      ,
      • Richardi U.
      • Frezza G.
      • Filippi A.R.
      • Badellino S.
      • Levis M.
      • Navarria P.
      • et al.
      Stereotactic ablative radiotherapy for stage I histologically proven non-small cell lung cancer: an Italian multicenter observational study.
      Lung cancer. 2014; 84: 248-253
      ,
      • Jeppesen S.S.
      • Schytte T.
      • Jensen H.R.
      • Brink C.
      • Hansen O.
      Stereotactic body radiation therapy versus conventional radiation therapy in patients with early stage non-small cell lung cancer: an updated retrospective study on local failure and survival rates.
      Acta Oncol. 2013; 52: 1552-1558
      ,
      • Guckenberger M.
      • Allgäuer M.
      • Appold S.
      • Dieckmann K.
      • Ernst I.
      • Ganswindt U.
      • et al.
      Safety and efficacy of stereotactic body radiotherapy for stage I non-small-cell lung cancer in routine clinical practice.
      J Thorac Oncol. 2013; 8: 1050-1058
      ,
      • Andratschke N.
      • Zimmermann F.
      • Boehm E.
      • Schill S.
      • Schoenknecht C.
      • Thamm R.
      • et al.
      Stereotactic radiotherapy of histologically proven inoperable stage I non-small cell lung cancer: patterns of failure.
      Radiother Oncol. 2011; 101: 245-249
      ,
      • Kopeck N.
      • Paludan M.
      • Petersen J.
      • Hansen A.T.
      • Grau C.
      • Høyer M.
      Co-morbidity index predicts for mortality after stereotactic body radiotherapy for medically inoperable early-stage non-small cell lung cancer.
      Radiother Oncol. 2009; 93: 402-407
      ,
      • Nyman J.
      • Johansson K.A.
      • Hultén U.
      Stereotactic hypofractionated radiotherapy for stage I non-small cell lung cancer – mature results for medically inoperable patients.
      Lung Cancer. 2006; 51: 97-103
      ,
      • Kastelijn E.A.
      • El Sharouni S.Y.
      • Hofman F.N.
      • Van Putte B.P.
      • Monninkhof E.M.
      • Van Vulpen M.
      • et al.
      Clinical outcomes in early-stage NSCLC treated with stereotactic body radiotherapy versus surgical resection.
      Anticancer Res. 2015; 35: 5607-5614
      ,
      • Peulen H.
      • Belderbos J.
      • Rossi M.
      • Sonke J.J.
      Mid-ventilation based PTV margins in stereotactic body radiotherapy (SBRT): a clinical evaluation.
      Radiother Oncol. 2014; 110: 511-516
      ,
      • Senthi S.
      • Lagerwaard F.J.
      • Haasbeek C.J.A.
      • Slotman B.J.
      • Senan S.
      Patterns of disease recurrence after stereotactic ablative radiotherapy for early stage non-small-cell lung cancer: a retrospective analysis.
      Lancet Oncol. 2012; 13: 802-809
      ,

      Van der Voort van Zyp NC, Prévost JB, Hoogeman MS, Praag J, van der Holt B, Levendag PC, et al. Stereotactic radiotherapy with real-time tumor tracking for non-small cell lung cancer: clinical outcome. 2009; 91: 296 - 300.

      ,
      • Lovinfosse P.
      • Janvary Z.L.
      • Coucke P.
      • Jodogne S.
      • Bernard C.
      • Hatt M.
      • et al.
      FDG PET/CT texture analysis for predicting the outcome of lung cancer treated by stereotactic body radiation therapy.
      Eur J Nucl Med Mol Imaging. 2016; 43: 1453-1460
      ,
      • Janssen S.
      • Kaesmann L.
      • Rudat V.
      • Rades D.
      Stereotactic body radiotherapy (SBRT) with lower doses for selected patients with stage I non-small-cell lung cancer (NSCLC).
      Lung. 2016; 194: 291-294
      ,
      • Duncker-Rohr V.
      • Nestle U.
      • Momm F.
      • Prokic V.
      • Heinemann F.
      • Mix M.
      • et al.
      Stereotactic ablative radiotherapy for small lung tumors with a moderate dose. Favorable results and low toxicity.
      Strahlenther Onkol. 2013; 189: 33-40
      ,
      • Fritz P.
      • Kraus H.J.
      • Blaschke T.
      • Mühlnickel W.
      • Strauch K.
      • Engel-Riedel W.
      • et al.
      Stereotactic, high single-dose irradiation of stage I non-small cell lung cancer (NSCLC) using four-dimensional CT scans for treatment planning.
      Lung Cancer. 2008; 60: 193-199
      ,
      • Hof H.
      • Muenter M.
      • Oetzel D.
      • Hoess A.
      • Debus J.
      • Herfarth K.
      Stereotactic single-dose radiotherapy (radiosurgery) of early stage nonsmall-cell lung cancer (NSCLC).
      Cancer. 2007; 110: 148-155
      ,
      • Wulf J.
      • Haedinger U.
      • Oppitz U.
      • Thiele W.
      • Mueller G.
      • Flentje M.
      Stereotactic radiotherapy for primary lung cancer and pulmonary metastases: a noninvasive treatment approach in medically inoperable patients.
      Int J Radiat Oncol Biol Phys. 2004; 60: 186-196
      ,
      • Scorsetti M.
      • Navarria P.
      • Facoetti A.
      • Lattuada P.
      • Urso G.
      • Mirandola A.
      • et al.
      Effectiveness of stereotactic body radiotherapy in the treatment of inoperable early-stage lung cancer.
      Anticancer Res. 2007; 27: 3615-3620
      ,
      • Onishi H.
      • Shirato H.
      • Nagata Y.
      • Hiraoka M.
      • Fujino M.
      • Gomi K.
      • et al.
      Hypofractionated stereotactic radiotherapy (HypoFXSRT) for stage I non-small cell lung cancer: updated results of 257 patients in a Japanese multi-institutional study.
      J Thorac Oncol. 2007; 2: S94-100
      ,
      • Tsurugai Y.
      • Kozuka T.
      • Ishizuka N.
      • Oguchi M.
      Relationship between the consolidation to maximum tumor diameter ratio and outcomes following stereotactic body radiotherapy for stage I non-small-cell lung cancer.
      Lung Cancer. 2016; 92: 47-52
      ,
      • Hayashi S.
      • Tanaka H.
      • Hoshi H.
      Imaging characteristics of local recurrences after stereotactic body radiation therapy for stage I non-small cell lung cancer: evaluation of mass-like fibrosis.
      Thorac Cancer. 2015; 6: 186-193
      ,
      • Shibamoto Y.
      • Hashizume C.
      • Baba F.
      • Ayakawa S.
      • Miyakawa A.
      • Murai T.
      • et al.
      Stereotactic body radiotherapy using a radiobiology-based regimen for stage I non-small-cell lung cancer.
      J Thorac Oncol. 2015; 10: 960-964
      ,
      • Yamamoto T.
      • Kadoya N.
      • Shirata Y.
      • Koto M.
      • Sato K.
      • Matsushita H.
      • et al.
      Impact of tumor attachment to the pleura measured by a pretreatment CT image on outcome of stage I NSCLC treated with stereotactic body radiotherapy.
      Radiat Oncol. 2015; 10: 35
      ,
      • Yoshitake T.
      • Nakamura K.
      • Shioyama Y.
      • Sasaki T.
      • Ohga S.
      • Shinoto M.
      • et al.
      Stereotactic body radiation therapy for primary lung cancers clinically diagnosed without pathological confirmation: a single-institution experience.
      Int J Clin Oncol. 2015; 20: 53-58
      ,
      • Satoh Y.
      • Onishi H.
      • Nambu A.
      • Araki T.
      Volume-based parameters measured by using FDG PET/CT in patients with stage I NSCLC treated with stereotactic body radiation therapy: prognostic value.
      Radiology. 2014; 270: 275-281
      ,
      • Yamashita H.
      • Haga A.
      • Takahashi W.
      • Takenaka R.
      • Imae T.
      • Takenaka S.
      • et al.
      Volumetric modulated arc therapy for lung stereotactic radiation therapy can achieve high local control rates.
      Radiat Oncol. 2014; 9: 243
      ,
      • Inoue T.
      • Katoh N.
      • Onimaru R.
      • Shimizu S.
      • Tsuchiya K.
      • Suzuki R.
      • et al.
      Stereotactic body radiotherapy using gated radiotherapy with real-time tumor-tracking for stage I non-small cell lung cancer.
      Radiat Oncol. 2013; 8: 69
      ,
      • Matsuo Y.
      • Shibuya K.
      • Nagata Y.
      • Takayama K.
      • Norihisa Y.
      • Mizowaki T.
      • et al.
      Prognostic factors in stereotactic body radiotherapy for non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2011; 79: 1104-1111
      ,
      • Hamamoto Y.
      • Kataoka M.
      • Yamashita M.
      • Shinkai T.
      • Kubo Y.
      • Sugawara Y.
      • et al.
      Local control of metastatic lung tumors treated with SBRT of 48 Gy in four fractions: in comparison with primary lung cancer.
      Jpn J Clin Oncol. 2010; 40: 125-129
      ,
      • Shen Z.T.
      • Wu X.H.
      • Li B.
      • Zhu X.X.
      Clinical outcomes of cyberknife stereotactic body radiotherapy for peripheral stage I non-small cell lung cancer.
      Med Oncol. 2015; 32: 55
      ,
      • Wu D.
      • Zhu H.
      • Tang H.
      • Li C.
      • Xu F.
      Clinical analysis of stereotactic body radiation therapy using extracranial gamma knife for patients with mainly bulky inoperable early stage non-small cell lung carcinoma.
      Radiat Oncol. 2011; 6: 84
      ,
      • Ng A.W.
      • Tung S.Y.
      • Wong V.Y.
      Hypofractionated stereotactic radiotherapy for medically inoperable stage I non-small cell lung cancer-report on clinical outcome and dose to critical organs.
      Radiother Oncol. 2008; 87: 24-28
      ,
      • Xia T.
      • Li H.
      • Sun Q.
      • Wang Y.
      • Fan N.
      • Yu Y.
      • et al.
      Promising clinical outcome of stereotactic body radiation therapy for patients with inoperable stage I/II non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2006; 66: 117-125
      ,
      • Kim M.J.
      • Yeo S.G.
      • Kim E.S.
      • Min C.K.
      • Se An P.
      Intensity-modulated stereotactic body radiotherapy for stage I non-small cell lung cancer.
      Oncol Lett. 2013; 5: 840-844
      ,
      • Song S.Y.
      • Choi W.
      • Shin S.S.
      • Lee S.W.
      • Ahn S.D.
      • Kim J.H.
      • et al.
      Fractionated stereotactic body radiation therapy for medically inoperable stage I lung cancer adjacent to central large bronchus.
      Lung Cancer. 2009; 66: 89-93
      ,
      • Baba F.
      • Shibamoto Y.
      • Ogino H.
      • Murata R.
      • Sugie C.
      • Iwata H.
      • et al.
      Clinical outcomes of stereotactic body radiotherapy for stage I non-small cell lung cancer using different doses depending on tumor size.
      Radiat Oncol. 2010; 5: 81
      ,
      • Bush D.A.
      • Cheek G.
      • Zaheer S.
      • Wallen J.
      • Mirshahidi H.
      • Katerelos A.
      • et al.
      High-dose hypofractionated proton beam radiation therapy is safe and effective for central and peripheral early-stage non-small cell lung cancer: results of a 12-year experience at Loma Linda University Medical Center.
      Int J Radiat Oncol Biol Phys. 2013; 86: 964-968
      ,
      • Miyamoto T.
      • Baba M.
      • Sugane T.
      • Nakajima M.
      • Yashiro T.
      • Kagei K.
      • et al.
      Carbon ion radiotherapy for stage I non-small cell lung cancer using a regimen of four fractions during 1 week.
      J Thorac Oncol. 2007; 2: 916-926
      ,
      • Miyamoto T.
      • Baba M.
      • Yamamoto N.
      • Koto M.
      • Sugawara T.
      • Yashiro T.
      • et al.
      Curative treatment of stage I non-small-cell lung cancer with carbon ion beams using a hypofractionated regimen.
      Int J Radiat Oncol Biol Phys. 2007; 67: 750-758
      ,
      • Karube M.
      • Yamamoto N.
      • Nakajima M.
      • Yamashita H.
      • Nakagawa K.
      • Miyamoto T.
      • et al.
      Single-fraction carbon-ion radiation therapy for patients 80 years of age and older with stage I non-small cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2016; 95: 542-548
      ,
      • Westover K.D.
      • Seco J.
      • Adams J.A.
      • Lanuti M.
      • Choi N.C.
      • Engelsman M.
      • et al.
      Proton SBRT for medically inoperable stage I NSCLC.
      J Thorac Oncol. 2012; 7: 1021-1025
      ,
      • Hatayama Y.
      • Nakamura T.
      • Suzuki M.
      • Azami Y.
      • Ono T.
      • Yabuuchi T.
      • et al.
      Clinical outcomes and prognostic factors of high-dose proton beam therapy for peripheral stage I non-small-cell lung cancer.
      Clin Lung Cancer. 2015; (in press)
      ,
      • Kanemoto A.
      • Okumura T.
      • Ishikawa H.
      • Mizumoto M.
      • Oshiro Y.
      • Kurishima K.
      • et al.
      Outcomes and prognostic factors for recurrence after high-dose proton beam therapy for centrally and peripherally located stage I non-small-cell lung cancer.
      Clin Lung Cancer. 2014; 15: e7-12
      ,
      • Fujii O.
      • Demizu Y.
      • Hashimoto N.
      • Takagi M.
      • Terashima K.
      • Mima M.
      • et al.
      Particle therapy for clinically diagnosed stage I lung cancer: comparison with pathologically proven non-small cell lung cancer.
      Acta Oncol. 2015; 54: 315-321
      ,
      • Fujii O.
      • Demizu Y.
      • Hashimoto N.
      • Araya M.
      • Takagi M.
      • Terashima K.
      • et al.
      A retrospective comparison of proton therapy and carbon ion therapy for stage I non-small cell lung cancer.
      Radiother Oncol. 2013; 109: 32-37
      ]. Relevant information on the long term clinical outcome was also extracted from an abstract for 1 phase 2 SBRT trial [
      • Timmerman R.
      • Paulus R.
      • Galvin J.
      • Michalski J.
      • Straube W.
      • Bradley J.
      • et al.
      Stereotactic body radiation therapy for inoperable early stage lung cancer.
      JAMA. 2010; 303: 1070-1076
      ,
      • Timmerman R.D.
      • Hu C.
      • Michalski J.
      • Straube W.
      • Galvin J.
      • Johnstone D.
      • et al.
      Long-term results of RTOG 0236: a phase II trial of stereotactic body radiation therapy (SBRT) in the treatment of patients with medically inoperable stage I non-small cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2014; 90: S30
      ]. Two SBRT studies reporting the results of the same phase 2 trial complemented each other, and were counted as 1 study. One phase 3 study comparing SBRT and surgery (only the SBRT data was used) [
      • Chang J.
      • Senan S.
      • Paul M.A.
      • Mehran R.J.
      • Louie A.V.
      • Balter P.
      • et al.
      Stereotactic ablative radiotherapy versus lobectomy for operable stage I non-small-cell lung cancer: a pooled analysis of two randomised trials.
      Lancet Oncol. 2015; 16: 630-637
      ], 10 phase 2 [
      • Timmerman R.
      • Paulus R.
      • Galvin J.
      • Michalski J.
      • Straube W.
      • Bradley J.
      • et al.
      Stereotactic body radiation therapy for inoperable early stage lung cancer.
      JAMA. 2010; 303: 1070-1076
      ,
      • Timmerman R.D.
      • Hu C.
      • Michalski J.
      • Straube W.
      • Galvin J.
      • Johnstone D.
      • et al.
      Long-term results of RTOG 0236: a phase II trial of stereotactic body radiation therapy (SBRT) in the treatment of patients with medically inoperable stage I non-small cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2014; 90: S30
      ,
      • Videtic G.M.
      • Hu C.
      • Singh A.K.
      • Chang J.Y.
      • Parker W.
      • Olivier K.R.
      • et al.
      A randomized phase 2 study comparing 2 stereotactic body radiation therapy schedules for medically inoperable patients with stage I peripheral non-small cell lung cancer: NRG Oncology RTOG 0915 (NCCTG N0927).
      Int J Radiat Oncol Biol Phys. 2015; 93: 757-764
      ,
      • Fakiris A.J.
      • McGarry R.C.
      • Yiannoutsos C.T.
      • Papiez L.
      • Williams M.
      • Henderson M.A.
      • et al.
      Stereotactic body radiation therapy for early-stage non-small-cell lung carcinoma: four-year results of a prospective phase II study.
      Int J Radiat Oncol Biol Phys. 2009; 75: 677-682
      ,
      • Baumann P.
      • Nyman J.
      • Hoyer M.
      • Wennberg B.
      • Gagliardi G.
      • Lax I.
      • et al.
      Outcome in a prospective phase II trial of medically inoperable stage I non-small-cell lung cancer patients treated with stereotactic body radiotherapy.
      J Clin Oncol. 2009; 27: 3290-3296
      ,
      • Lindberg K.
      • Nyman J.
      • Källskog V.R.
      • Hoyer M.
      • Lund J.Ǻ.
      • Lax I.
      • et al.
      Long-term results of a prospective phase II trial of medically inoperable stage I NSCLC treated with SBRT – the Nordic experience.
      Acta Oncol. 2015; 54: 1096-1104
      ,
      • Navarro-Martin A.
      • Aso S.
      • Cacicedo J.
      • Arnaiz M.
      • Navarro V.
      • Rosales S.
      • et al.
      Phase II trial of SBRT for stage I NSCLC: survival, local control, and lung function at 36 months.
      J Thorac Oncol. 2016; (In press)
      ,
      • Bral S.
      • Gevaert T.
      • Linthout N.
      • Versmessen H.
      • Collen C.
      • Engels B.
      • et al.
      Prospective, risk-adapted strategy of stereotactic body radiotherapy for early-stage non-small-cell lung cancer: results of a phase II trial.
      Int J Radiat Oncol Biol Phys. 2011; 80: 1343-1349
      ,
      • Ricardi U.
      • Filippi A.R.
      • Guarneri A.
      • Giglioli F.R.
      • Ciammella P.
      • Franco P.
      • et al.
      Stereotactic body radiation therapy for early stage non-small cell lung cancer: results of a prospective trial.
      Lung Cancer. 2010; 68: 72-77
      ,
      • Nagata Y.
      • Hiraoka M.
      • Shibata T.
      • Onishi H.
      • Kokubo M.
      • Karasawa K.
      • et al.
      Prospective trial of stereotactic body radiation therapy for both operable and inoperable T1N0M0 non-small cell lung cancer: Japan Clinical Oncology Group Study JCOG0403.
      Int J Radiat Oncol Biol Phys. 2015; 93: 989-996
      ,
      • Koto M.
      • Takai Y.
      • Ogawa Y.
      • Matsushita H.
      • Takeda K.
      • Takahashi C.
      • et al.
      A phase II study on stereotactic body radiotherapy for stage I non-small cell lung cancer.
      Radiother Oncol. 2007; 85: 429-434
      ,
      • Onishi H.
      • Kuriyama K.
      • Komiyama T.
      • Tanaka S.
      • Sano N.
      • Marino K.
      • et al.
      Clinical outcomes of stereotactic radiotherapy for stage I non-small cell lung cancer using a novel irradiation technique: patient self-controlled breath-hold and beam switching using a combination of linear accelerator and CT scanner.
      Lung Cancer. 2004; 45: 45-55
      ], 1 phase 1 [
      • Onimaru R.
      • Shirato H.
      • Shibata T.
      • Hiraoka M.
      • Ishikura S.
      • Karasawa K.
      • et al.
      Phase I study of stereotactic body radiation therapy for peripheral T2N0M0 non-small cell lung cancer with PTV∗∗ 100 cc using a continual reassessment method (JCOG0702).
      Radiother Oncol. 2015; 116: 276-280
      ], and 56 retrospective [
      • Chiang A.
      • Thibault I.
      • Warner A.
      • Rodrigues G.
      • Palma D.
      • Soliman H.
      • et al.
      A comparison between accelerated hypofractionation and stereotactic ablative radiotherapy (SABR) for early-stage non-small cell lung cancer (NSCLC): results of a propensity score-matched analysis.
      Radiother Oncol. 2016; 118: 478-484
      ,
      • Taremi M.
      • Hope A.
      • Dahele M.
      • Pearson S.
      • Fung S.
      • Purdie T.
      • et al.
      Stereotactic body radiotherapy for medically inoperable lung cancer: prospective, single-center study of 108 consecutive patients.
      Int J Radiat Oncol Biol Phys. 2012; 82: 967-973
      ,
      • Mak R.H.
      • Hermann G.
      • Lewis J.H.
      • Aerts H.J.W.L.
      • Baldini E.H.
      • Chen A.B.
      • et al.
      Outcomes by tumor histology and KRAS mutation status after lung stereotactic body radiation therapy for early-stage non-small-cell lung cancer.
      Clin Lung Cancer. 2015; 16: 24-32
      ,
      • Ebright M.I.
      • Russo G.A.
      • Gupta A.
      • Subramaniam R.M.
      • Fernando H.C.
      • Kachnic L.A.
      Positron emission tomography combined with diagnostic chest computed tomography enhances detection of regional recurrence after stereotactic body radiation therapy for early stage non-small cell lung cancer.
      J Thorac Cardiovasc Surg. 2013; 145: 709-715
      ,
      • Park H.S.
      • Harder E.M.
      • Mancini B.R.
      • Decker R.H.
      Central versus peripheral tumor location: influence on survival, local control, and toxicity following stereotactic body radiotherapy for primary non-small-cell lung cancer.
      J Thorac Oncol. 2015; 10: 832-837
      ,
      • Spratt D.E.
      • Wu A.J.
      • Adeseye V.
      • Din S.U.
      • Shaikh F.
      • Woo K.M.
      • et al.
      Recurrence patterns and second primary lung cancers after stereotactic body radiation therapy for early-stage non-small-cell lung cancer: implications for surveillance.
      Clin Lung Cancer. 2015; 17: 177-183
      ,
      • Parashar B.
      • Port J.
      • Arora S.
      • Christos P.
      • Trichter S.
      • Nori D.
      • et al.
      Analysis of stereotactic body radiation vs. wedge resection vs. wedge resection plus cesium-131 brachytherapy in early stage lung cancer.
      Brachytherapy. 2015; 14: 648-654
      ,
      • Kelley K.D.
      • Benninghoff D.L.
      • Stein J.S.
      • Li J.Z.
      • Byrnes R.T.
      • Potters L.
      • et al.
      Medically inoperable peripheral lung cancer treated with stereotactic body radiation therapy.
      Radiat Oncol. 2015; 10: 120
      ,
      • Vu C.C.
      • Matthews R.
      • Kim B.
      • Franceschi D.
      • Bilfinger T.V.
      • Moore W.H.
      Prognostic value of metabolic tumor volume and total lesion glycolysis from 18F-FDG PET/CT in patients undergoing stereotactic body radiation therapy for stage I non-small-cell lung cancer.
      Nucl Med Commun. 2013; 34: 959-963
      ,
      • Horne Z.D.
      • Clump D.A.
      • Vargo J.A.
      • Shah S.
      • Beriwal S.
      • Burton S.A.
      • et al.
      Pretreatment SUVmax predicts progression-free survival in early-stage non-small cell lung cancer treated with stereotactic body radiation therapy.
      Radiat Oncol. 2014; 9: 41
      ,
      • Vahdat S.
      • Oermann E.K.
      • Collins S.P.
      • Yu X.
      • Abedalthagafi M.
      • DeBrito P.
      • et al.
      Cyberknife radiosurgery for inoperable stage IA non-small cell lung cancer: 18F-fluorodeoxyglucose positron emission tomography/computed tomography serial tumor response assessment.
      J Hem Oncol. 2010; 3: 6
      ,
      • Dunlap N.E.
      • Larner J.M.
      • Read P.W.
      • Kozower B.D.
      • Lau C.L.
      • Sheng K.
      • et al.
      Size matters: a comparison of T1 and T2 peripheral non-small-cell lung cnacers treated with stereotactic body radiation therapy (SBRT).
      J Thorac Cardiovasc Surg. 2010; 140: 583-589
      ,
      • Brown W.T.
      • Wu X.
      • Fayad F.
      • Fowler J.F.
      • García S.
      • Monterroso M.I.
      • et al.
      Application of robotic stereotactic radiotherapy to peripheral stage I non-small cell lung cancer with curative intent.
      Clin Oncol. 2009; 21: 623-631
      ,
      • Grills I.S.
      • Hope A.J.
      • Guckenberger M.
      • Kestin L.L.
      • Werner-Wasik M.
      • Yan D.
      • et al.
      A collaborative analysis of stereotactic lung radiotherapy outcomes for early-stage non-small-cell lung cancer using daily online cone-beam computed tomography image-guided radiotherapy.
      J Thorac Oncol. 2012; 7: 1382-1393
      ,
      • Videtic G.M.
      • Stephans K.L.
      • Woody N.M.
      • Reddy C.A.
      • Zhuang T.
      • Magnelli A.
      • et al.
      30 Gy or 34 Gy? Comparing 2 single-fraction SBRT dose schedules for stage I medically inoperable non-small cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2014; 90: 203-208
      ,
      • Burdick M.J.
      • Stephans K.L.
      • Reddy C.A.
      • Djemil T.
      • Srinivas S.M.
      • Videtic G.M.
      Maximum standardized uptake value from staging FDG-PET/CT does not predict treatment outcome for early-stage non-small-cell lung cancer treated with stereotactic body radiotherapy.
      Int J Radiat Oncol Biol Phys. 2010; 78: 1033-1039
      ,
      • Fischer-Valuck B.W.
      • Boggs H.
      • Katz S.
      • Durci M.
      • Acharya S.
      • Rosen L.R.
      Comparison of stereotactic body radiation therapy for biopsy-proven versus radiographically diagnosed early-stage non-small lung cancer: a single-institution experience.
      Tumori. 2015; 10: 287-293
      ,
      • Zhang X.
      • Liu H.
      • Balter P.
      • Allen P.K.
      • Komaki R.
      • Pan T.
      • et al.
      Positron emission tomography for assessing local failure after stereotactic body radiotherapy for non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2012; 83: 1558-1565
      ,
      • Shultz D.B.
      • Trakul N.
      • Abelson J.A.
      • Murphy J.D.
      • Maxim P.G.
      • Le Q.T.
      • et al.
      Imaging features associated with disease progression after stereotactic ablative radiotherapy for stage I non-small-cell lung cancer.
      Clin Lung Cancer. 2014; 15: 294-301
      ,
      • Shaverdian N.
      • Veruttipong D.
      • Wang J.
      • Schaue D.
      • Kupelian P.
      • Lee P.
      Pretreatment immune parameters predict for overall survival and toxicity in early-stage non-small-cell lung cancer patients treated with stereotactic body radiation therapy.
      Clin Lung Cancer. 2016; 17: 39-46
      ,
      • Nath S.K.
      • Sandhu A.P.
      • Kim D.
      • Bharne A.
      • Nobiensky P.D.
      • Lawson J.D.
      • et al.
      Locoregional and distant failure following image-guided stereotactic body radiation for early-stage primary lung cancer.
      Radiother Oncol. 2011; 99: 12-17
      ,
      • Olsen J.R.
      • Robinson C.G.
      • El Naqa I.
      • Creach K.M.
      • Drzymala R.E.
      • Parikh P.J.
      • et al.
      Dose-response for stereotactic body radiotherapy in early-stage non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2011; 81: e299-303
      ,
      • Richardi U.
      • Frezza G.
      • Filippi A.R.
      • Badellino S.
      • Levis M.
      • Navarria P.
      • et al.
      Stereotactic ablative radiotherapy for stage I histologically proven non-small cell lung cancer: an Italian multicenter observational study.
      Lung cancer. 2014; 84: 248-253
      ,
      • Jeppesen S.S.
      • Schytte T.
      • Jensen H.R.
      • Brink C.
      • Hansen O.
      Stereotactic body radiation therapy versus conventional radiation therapy in patients with early stage non-small cell lung cancer: an updated retrospective study on local failure and survival rates.
      Acta Oncol. 2013; 52: 1552-1558
      ,
      • Guckenberger M.
      • Allgäuer M.
      • Appold S.
      • Dieckmann K.
      • Ernst I.
      • Ganswindt U.
      • et al.
      Safety and efficacy of stereotactic body radiotherapy for stage I non-small-cell lung cancer in routine clinical practice.
      J Thorac Oncol. 2013; 8: 1050-1058
      ,
      • Andratschke N.
      • Zimmermann F.
      • Boehm E.
      • Schill S.
      • Schoenknecht C.
      • Thamm R.
      • et al.
      Stereotactic radiotherapy of histologically proven inoperable stage I non-small cell lung cancer: patterns of failure.
      Radiother Oncol. 2011; 101: 245-249
      ,
      • Kopeck N.
      • Paludan M.
      • Petersen J.
      • Hansen A.T.
      • Grau C.
      • Høyer M.
      Co-morbidity index predicts for mortality after stereotactic body radiotherapy for medically inoperable early-stage non-small cell lung cancer.
      Radiother Oncol. 2009; 93: 402-407
      ,
      • Nyman J.
      • Johansson K.A.
      • Hultén U.
      Stereotactic hypofractionated radiotherapy for stage I non-small cell lung cancer – mature results for medically inoperable patients.
      Lung Cancer. 2006; 51: 97-103
      ,
      • Kastelijn E.A.
      • El Sharouni S.Y.
      • Hofman F.N.
      • Van Putte B.P.
      • Monninkhof E.M.
      • Van Vulpen M.
      • et al.
      Clinical outcomes in early-stage NSCLC treated with stereotactic body radiotherapy versus surgical resection.
      Anticancer Res. 2015; 35: 5607-5614
      ,
      • Peulen H.
      • Belderbos J.
      • Rossi M.
      • Sonke J.J.
      Mid-ventilation based PTV margins in stereotactic body radiotherapy (SBRT): a clinical evaluation.
      Radiother Oncol. 2014; 110: 511-516
      ,
      • Senthi S.
      • Lagerwaard F.J.
      • Haasbeek C.J.A.
      • Slotman B.J.
      • Senan S.
      Patterns of disease recurrence after stereotactic ablative radiotherapy for early stage non-small-cell lung cancer: a retrospective analysis.
      Lancet Oncol. 2012; 13: 802-809
      ,

      Van der Voort van Zyp NC, Prévost JB, Hoogeman MS, Praag J, van der Holt B, Levendag PC, et al. Stereotactic radiotherapy with real-time tumor tracking for non-small cell lung cancer: clinical outcome. 2009; 91: 296 - 300.

      ,
      • Lovinfosse P.
      • Janvary Z.L.
      • Coucke P.
      • Jodogne S.
      • Bernard C.
      • Hatt M.
      • et al.
      FDG PET/CT texture analysis for predicting the outcome of lung cancer treated by stereotactic body radiation therapy.
      Eur J Nucl Med Mol Imaging. 2016; 43: 1453-1460
      ,
      • Janssen S.
      • Kaesmann L.
      • Rudat V.
      • Rades D.
      Stereotactic body radiotherapy (SBRT) with lower doses for selected patients with stage I non-small-cell lung cancer (NSCLC).
      Lung. 2016; 194: 291-294
      ,
      • Duncker-Rohr V.
      • Nestle U.
      • Momm F.
      • Prokic V.
      • Heinemann F.
      • Mix M.
      • et al.
      Stereotactic ablative radiotherapy for small lung tumors with a moderate dose. Favorable results and low toxicity.
      Strahlenther Onkol. 2013; 189: 33-40
      ,
      • Fritz P.
      • Kraus H.J.
      • Blaschke T.
      • Mühlnickel W.
      • Strauch K.
      • Engel-Riedel W.
      • et al.
      Stereotactic, high single-dose irradiation of stage I non-small cell lung cancer (NSCLC) using four-dimensional CT scans for treatment planning.
      Lung Cancer. 2008; 60: 193-199
      ,
      • Hof H.
      • Muenter M.
      • Oetzel D.
      • Hoess A.
      • Debus J.
      • Herfarth K.
      Stereotactic single-dose radiotherapy (radiosurgery) of early stage nonsmall-cell lung cancer (NSCLC).
      Cancer. 2007; 110: 148-155
      ,
      • Wulf J.
      • Haedinger U.
      • Oppitz U.
      • Thiele W.
      • Mueller G.
      • Flentje M.
      Stereotactic radiotherapy for primary lung cancer and pulmonary metastases: a noninvasive treatment approach in medically inoperable patients.
      Int J Radiat Oncol Biol Phys. 2004; 60: 186-196
      ,
      • Scorsetti M.
      • Navarria P.
      • Facoetti A.
      • Lattuada P.
      • Urso G.
      • Mirandola A.
      • et al.
      Effectiveness of stereotactic body radiotherapy in the treatment of inoperable early-stage lung cancer.
      Anticancer Res. 2007; 27: 3615-3620
      ,
      • Onishi H.
      • Shirato H.
      • Nagata Y.
      • Hiraoka M.
      • Fujino M.
      • Gomi K.
      • et al.
      Hypofractionated stereotactic radiotherapy (HypoFXSRT) for stage I non-small cell lung cancer: updated results of 257 patients in a Japanese multi-institutional study.
      J Thorac Oncol. 2007; 2: S94-100
      ,
      • Tsurugai Y.
      • Kozuka T.
      • Ishizuka N.
      • Oguchi M.
      Relationship between the consolidation to maximum tumor diameter ratio and outcomes following stereotactic body radiotherapy for stage I non-small-cell lung cancer.
      Lung Cancer. 2016; 92: 47-52
      ,
      • Hayashi S.
      • Tanaka H.
      • Hoshi H.
      Imaging characteristics of local recurrences after stereotactic body radiation therapy for stage I non-small cell lung cancer: evaluation of mass-like fibrosis.
      Thorac Cancer. 2015; 6: 186-193
      ,
      • Shibamoto Y.
      • Hashizume C.
      • Baba F.
      • Ayakawa S.
      • Miyakawa A.
      • Murai T.
      • et al.
      Stereotactic body radiotherapy using a radiobiology-based regimen for stage I non-small-cell lung cancer.
      J Thorac Oncol. 2015; 10: 960-964
      ,
      • Yamamoto T.
      • Kadoya N.
      • Shirata Y.
      • Koto M.
      • Sato K.
      • Matsushita H.
      • et al.
      Impact of tumor attachment to the pleura measured by a pretreatment CT image on outcome of stage I NSCLC treated with stereotactic body radiotherapy.
      Radiat Oncol. 2015; 10: 35
      ,
      • Yoshitake T.
      • Nakamura K.
      • Shioyama Y.
      • Sasaki T.
      • Ohga S.
      • Shinoto M.
      • et al.
      Stereotactic body radiation therapy for primary lung cancers clinically diagnosed without pathological confirmation: a single-institution experience.
      Int J Clin Oncol. 2015; 20: 53-58
      ,
      • Satoh Y.
      • Onishi H.
      • Nambu A.
      • Araki T.
      Volume-based parameters measured by using FDG PET/CT in patients with stage I NSCLC treated with stereotactic body radiation therapy: prognostic value.
      Radiology. 2014; 270: 275-281
      ,
      • Yamashita H.
      • Haga A.
      • Takahashi W.
      • Takenaka R.
      • Imae T.
      • Takenaka S.
      • et al.
      Volumetric modulated arc therapy for lung stereotactic radiation therapy can achieve high local control rates.
      Radiat Oncol. 2014; 9: 243
      ,
      • Inoue T.
      • Katoh N.
      • Onimaru R.
      • Shimizu S.
      • Tsuchiya K.
      • Suzuki R.
      • et al.
      Stereotactic body radiotherapy using gated radiotherapy with real-time tumor-tracking for stage I non-small cell lung cancer.
      Radiat Oncol. 2013; 8: 69
      ,
      • Matsuo Y.
      • Shibuya K.
      • Nagata Y.
      • Takayama K.
      • Norihisa Y.
      • Mizowaki T.
      • et al.
      Prognostic factors in stereotactic body radiotherapy for non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2011; 79: 1104-1111
      ,
      • Hamamoto Y.
      • Kataoka M.
      • Yamashita M.
      • Shinkai T.
      • Kubo Y.
      • Sugawara Y.
      • et al.
      Local control of metastatic lung tumors treated with SBRT of 48 Gy in four fractions: in comparison with primary lung cancer.
      Jpn J Clin Oncol. 2010; 40: 125-129
      ,
      • Shen Z.T.
      • Wu X.H.
      • Li B.
      • Zhu X.X.
      Clinical outcomes of cyberknife stereotactic body radiotherapy for peripheral stage I non-small cell lung cancer.
      Med Oncol. 2015; 32: 55
      ,
      • Wu D.
      • Zhu H.
      • Tang H.
      • Li C.
      • Xu F.
      Clinical analysis of stereotactic body radiation therapy using extracranial gamma knife for patients with mainly bulky inoperable early stage non-small cell lung carcinoma.
      Radiat Oncol. 2011; 6: 84
      ,
      • Ng A.W.
      • Tung S.Y.
      • Wong V.Y.
      Hypofractionated stereotactic radiotherapy for medically inoperable stage I non-small cell lung cancer-report on clinical outcome and dose to critical organs.
      Radiother Oncol. 2008; 87: 24-28
      ,
      • Xia T.
      • Li H.
      • Sun Q.
      • Wang Y.
      • Fan N.
      • Yu Y.
      • et al.
      Promising clinical outcome of stereotactic body radiation therapy for patients with inoperable stage I/II non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2006; 66: 117-125
      ,
      • Kim M.J.
      • Yeo S.G.
      • Kim E.S.
      • Min C.K.
      • Se An P.
      Intensity-modulated stereotactic body radiotherapy for stage I non-small cell lung cancer.
      Oncol Lett. 2013; 5: 840-844
      ,
      • Song S.Y.
      • Choi W.
      • Shin S.S.
      • Lee S.W.
      • Ahn S.D.
      • Kim J.H.
      • et al.
      Fractionated stereotactic body radiation therapy for medically inoperable stage I lung cancer adjacent to central large bronchus.
      Lung Cancer. 2009; 66: 89-93
      ] photon SBRT studies were included in the survival outcome comparison analysis. Among them, treatment-related toxicities were reported in all the prospective studies [
      • Chang J.
      • Senan S.
      • Paul M.A.
      • Mehran R.J.
      • Louie A.V.
      • Balter P.
      • et al.
      Stereotactic ablative radiotherapy versus lobectomy for operable stage I non-small-cell lung cancer: a pooled analysis of two randomised trials.
      Lancet Oncol. 2015; 16: 630-637
      ,
      • Timmerman R.
      • Paulus R.
      • Galvin J.
      • Michalski J.
      • Straube W.
      • Bradley J.
      • et al.
      Stereotactic body radiation therapy for inoperable early stage lung cancer.
      JAMA. 2010; 303: 1070-1076
      ,
      • Timmerman R.D.
      • Hu C.
      • Michalski J.
      • Straube W.
      • Galvin J.
      • Johnstone D.
      • et al.
      Long-term results of RTOG 0236: a phase II trial of stereotactic body radiation therapy (SBRT) in the treatment of patients with medically inoperable stage I non-small cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2014; 90: S30
      ,
      • Videtic G.M.
      • Hu C.
      • Singh A.K.
      • Chang J.Y.
      • Parker W.
      • Olivier K.R.
      • et al.
      A randomized phase 2 study comparing 2 stereotactic body radiation therapy schedules for medically inoperable patients with stage I peripheral non-small cell lung cancer: NRG Oncology RTOG 0915 (NCCTG N0927).
      Int J Radiat Oncol Biol Phys. 2015; 93: 757-764
      ,
      • Fakiris A.J.
      • McGarry R.C.
      • Yiannoutsos C.T.
      • Papiez L.
      • Williams M.
      • Henderson M.A.
      • et al.
      Stereotactic body radiation therapy for early-stage non-small-cell lung carcinoma: four-year results of a prospective phase II study.
      Int J Radiat Oncol Biol Phys. 2009; 75: 677-682
      ,
      • Baumann P.
      • Nyman J.
      • Hoyer M.
      • Wennberg B.
      • Gagliardi G.
      • Lax I.
      • et al.
      Outcome in a prospective phase II trial of medically inoperable stage I non-small-cell lung cancer patients treated with stereotactic body radiotherapy.
      J Clin Oncol. 2009; 27: 3290-3296
      ,
      • Lindberg K.
      • Nyman J.
      • Källskog V.R.
      • Hoyer M.
      • Lund J.Ǻ.
      • Lax I.
      • et al.
      Long-term results of a prospective phase II trial of medically inoperable stage I NSCLC treated with SBRT – the Nordic experience.
      Acta Oncol. 2015; 54: 1096-1104
      ,
      • Navarro-Martin A.
      • Aso S.
      • Cacicedo J.
      • Arnaiz M.
      • Navarro V.
      • Rosales S.
      • et al.
      Phase II trial of SBRT for stage I NSCLC: survival, local control, and lung function at 36 months.
      J Thorac Oncol. 2016; (In press)
      ,
      • Bral S.
      • Gevaert T.
      • Linthout N.
      • Versmessen H.
      • Collen C.
      • Engels B.
      • et al.
      Prospective, risk-adapted strategy of stereotactic body radiotherapy for early-stage non-small-cell lung cancer: results of a phase II trial.
      Int J Radiat Oncol Biol Phys. 2011; 80: 1343-1349
      ,
      • Ricardi U.
      • Filippi A.R.
      • Guarneri A.
      • Giglioli F.R.
      • Ciammella P.
      • Franco P.
      • et al.
      Stereotactic body radiation therapy for early stage non-small cell lung cancer: results of a prospective trial.
      Lung Cancer. 2010; 68: 72-77
      ,
      • Nagata Y.
      • Hiraoka M.
      • Shibata T.
      • Onishi H.
      • Kokubo M.
      • Karasawa K.
      • et al.
      Prospective trial of stereotactic body radiation therapy for both operable and inoperable T1N0M0 non-small cell lung cancer: Japan Clinical Oncology Group Study JCOG0403.
      Int J Radiat Oncol Biol Phys. 2015; 93: 989-996
      ,
      • Koto M.
      • Takai Y.
      • Ogawa Y.
      • Matsushita H.
      • Takeda K.
      • Takahashi C.
      • et al.
      A phase II study on stereotactic body radiotherapy for stage I non-small cell lung cancer.
      Radiother Oncol. 2007; 85: 429-434
      ,
      • Onishi H.
      • Kuriyama K.
      • Komiyama T.
      • Tanaka S.
      • Sano N.
      • Marino K.
      • et al.
      Clinical outcomes of stereotactic radiotherapy for stage I non-small cell lung cancer using a novel irradiation technique: patient self-controlled breath-hold and beam switching using a combination of linear accelerator and CT scanner.
      Lung Cancer. 2004; 45: 45-55
      ,
      • Onimaru R.
      • Shirato H.
      • Shibata T.
      • Hiraoka M.
      • Ishikura S.
      • Karasawa K.
      • et al.
      Phase I study of stereotactic body radiation therapy for peripheral T2N0M0 non-small cell lung cancer with PTV∗∗ 100 cc using a continual reassessment method (JCOG0702).
      Radiother Oncol. 2015; 116: 276-280
      ], and 40 retrospective studies [
      • Taremi M.
      • Hope A.
      • Dahele M.
      • Pearson S.
      • Fung S.
      • Purdie T.
      • et al.
      Stereotactic body radiotherapy for medically inoperable lung cancer: prospective, single-center study of 108 consecutive patients.
      Int J Radiat Oncol Biol Phys. 2012; 82: 967-973
      ,
      • Park H.S.
      • Harder E.M.
      • Mancini B.R.
      • Decker R.H.
      Central versus peripheral tumor location: influence on survival, local control, and toxicity following stereotactic body radiotherapy for primary non-small-cell lung cancer.
      J Thorac Oncol. 2015; 10: 832-837
      ,
      • Parashar B.
      • Port J.
      • Arora S.
      • Christos P.
      • Trichter S.
      • Nori D.
      • et al.
      Analysis of stereotactic body radiation vs. wedge resection vs. wedge resection plus cesium-131 brachytherapy in early stage lung cancer.
      Brachytherapy. 2015; 14: 648-654
      ,
      • Kelley K.D.
      • Benninghoff D.L.
      • Stein J.S.
      • Li J.Z.
      • Byrnes R.T.
      • Potters L.
      • et al.
      Medically inoperable peripheral lung cancer treated with stereotactic body radiation therapy.
      Radiat Oncol. 2015; 10: 120
      ,
      • Horne Z.D.
      • Clump D.A.
      • Vargo J.A.
      • Shah S.
      • Beriwal S.
      • Burton S.A.
      • et al.
      Pretreatment SUVmax predicts progression-free survival in early-stage non-small cell lung cancer treated with stereotactic body radiation therapy.
      Radiat Oncol. 2014; 9: 41
      ,
      • Dunlap N.E.
      • Larner J.M.
      • Read P.W.
      • Kozower B.D.
      • Lau C.L.
      • Sheng K.
      • et al.
      Size matters: a comparison of T1 and T2 peripheral non-small-cell lung cnacers treated with stereotactic body radiation therapy (SBRT).
      J Thorac Cardiovasc Surg. 2010; 140: 583-589
      ,
      • Brown W.T.
      • Wu X.
      • Fayad F.
      • Fowler J.F.
      • García S.
      • Monterroso M.I.
      • et al.
      Application of robotic stereotactic radiotherapy to peripheral stage I non-small cell lung cancer with curative intent.
      Clin Oncol. 2009; 21: 623-631
      ,
      • Grills I.S.
      • Hope A.J.
      • Guckenberger M.
      • Kestin L.L.
      • Werner-Wasik M.
      • Yan D.
      • et al.
      A collaborative analysis of stereotactic lung radiotherapy outcomes for early-stage non-small-cell lung cancer using daily online cone-beam computed tomography image-guided radiotherapy.
      J Thorac Oncol. 2012; 7: 1382-1393
      ,
      • Videtic G.M.
      • Stephans K.L.
      • Woody N.M.
      • Reddy C.A.
      • Zhuang T.
      • Magnelli A.
      • et al.
      30 Gy or 34 Gy? Comparing 2 single-fraction SBRT dose schedules for stage I medically inoperable non-small cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2014; 90: 203-208
      ,
      • Fischer-Valuck B.W.
      • Boggs H.
      • Katz S.
      • Durci M.
      • Acharya S.
      • Rosen L.R.
      Comparison of stereotactic body radiation therapy for biopsy-proven versus radiographically diagnosed early-stage non-small lung cancer: a single-institution experience.
      Tumori. 2015; 10: 287-293
      ,
      • Trakul N.
      • Chang C.N.
      • Harris J.
      • Chapman C.
      • Rao A.
      • Shen J.
      • et al.
      Tumor volume-adpated dosing in stereotactic ablative radiotherapy of lung tumors.
      Int J Radiat Oncol Biol Phys. 2012; 84: 231-237
      ,
      • Shaverdian N.
      • Veruttipong D.
      • Wang J.
      • Schaue D.
      • Kupelian P.
      • Lee P.
      Pretreatment immune parameters predict for overall survival and toxicity in early-stage non-small-cell lung cancer patients treated with stereotactic body radiation therapy.
      Clin Lung Cancer. 2016; 17: 39-46
      ,
      • Nath S.K.
      • Sandhu A.P.
      • Kim D.
      • Bharne A.
      • Nobiensky P.D.
      • Lawson J.D.
      • et al.
      Locoregional and distant failure following image-guided stereotactic body radiation for early-stage primary lung cancer.
      Radiother Oncol. 2011; 99: 12-17
      ,
      • Olsen J.R.
      • Robinson C.G.
      • El Naqa I.
      • Creach K.M.
      • Drzymala R.E.
      • Parikh P.J.
      • et al.
      Dose-response for stereotactic body radiotherapy in early-stage non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2011; 81: e299-303
      ,
      • Richardi U.
      • Frezza G.
      • Filippi A.R.
      • Badellino S.
      • Levis M.
      • Navarria P.
      • et al.
      Stereotactic ablative radiotherapy for stage I histologically proven non-small cell lung cancer: an Italian multicenter observational study.
      Lung cancer. 2014; 84: 248-253
      ,
      • Jeppesen S.S.
      • Schytte T.
      • Jensen H.R.
      • Brink C.
      • Hansen O.
      Stereotactic body radiation therapy versus conventional radiation therapy in patients with early stage non-small cell lung cancer: an updated retrospective study on local failure and survival rates.
      Acta Oncol. 2013; 52: 1552-1558
      ,
      • Guckenberger M.
      • Allgäuer M.
      • Appold S.
      • Dieckmann K.
      • Ernst I.
      • Ganswindt U.
      • et al.
      Safety and efficacy of stereotactic body radiotherapy for stage I non-small-cell lung cancer in routine clinical practice.
      J Thorac Oncol. 2013; 8: 1050-1058
      ,
      • Andratschke N.
      • Zimmermann F.
      • Boehm E.
      • Schill S.
      • Schoenknecht C.
      • Thamm R.
      • et al.
      Stereotactic radiotherapy of histologically proven inoperable stage I non-small cell lung cancer: patterns of failure.
      Radiother Oncol. 2011; 101: 245-249
      ,
      • Kopeck N.
      • Paludan M.
      • Petersen J.
      • Hansen A.T.
      • Grau C.
      • Høyer M.
      Co-morbidity index predicts for mortality after stereotactic body radiotherapy for medically inoperable early-stage non-small cell lung cancer.
      Radiother Oncol. 2009; 93: 402-407
      ,
      • Nyman J.
      • Johansson K.A.
      • Hultén U.
      Stereotactic hypofractionated radiotherapy for stage I non-small cell lung cancer – mature results for medically inoperable patients.
      Lung Cancer. 2006; 51: 97-103
      ,

      Van der Voort van Zyp NC, Prévost JB, Hoogeman MS, Praag J, van der Holt B, Levendag PC, et al. Stereotactic radiotherapy with real-time tumor tracking for non-small cell lung cancer: clinical outcome. 2009; 91: 296 - 300.

      ,
      • Janssen S.
      • Kaesmann L.
      • Rudat V.
      • Rades D.
      Stereotactic body radiotherapy (SBRT) with lower doses for selected patients with stage I non-small-cell lung cancer (NSCLC).
      Lung. 2016; 194: 291-294
      ,
      • Duncker-Rohr V.
      • Nestle U.
      • Momm F.
      • Prokic V.
      • Heinemann F.
      • Mix M.
      • et al.
      Stereotactic ablative radiotherapy for small lung tumors with a moderate dose. Favorable results and low toxicity.
      Strahlenther Onkol. 2013; 189: 33-40
      ,
      • Fritz P.
      • Kraus H.J.
      • Blaschke T.
      • Mühlnickel W.
      • Strauch K.
      • Engel-Riedel W.
      • et al.
      Stereotactic, high single-dose irradiation of stage I non-small cell lung cancer (NSCLC) using four-dimensional CT scans for treatment planning.
      Lung Cancer. 2008; 60: 193-199
      ,
      • Hof H.
      • Muenter M.
      • Oetzel D.
      • Hoess A.
      • Debus J.
      • Herfarth K.
      Stereotactic single-dose radiotherapy (radiosurgery) of early stage nonsmall-cell lung cancer (NSCLC).
      Cancer. 2007; 110: 148-155
      ,
      • Wulf J.
      • Haedinger U.
      • Oppitz U.
      • Thiele W.
      • Mueller G.
      • Flentje M.
      Stereotactic radiotherapy for primary lung cancer and pulmonary metastases: a noninvasive treatment approach in medically inoperable patients.
      Int J Radiat Oncol Biol Phys. 2004; 60: 186-196
      ,
      • Scorsetti M.
      • Navarria P.
      • Facoetti A.
      • Lattuada P.
      • Urso G.
      • Mirandola A.
      • et al.
      Effectiveness of stereotactic body radiotherapy in the treatment of inoperable early-stage lung cancer.
      Anticancer Res. 2007; 27: 3615-3620
      ,
      • Onishi H.
      • Shirato H.
      • Nagata Y.
      • Hiraoka M.
      • Fujino M.
      • Gomi K.
      • et al.
      Hypofractionated stereotactic radiotherapy (HypoFXSRT) for stage I non-small cell lung cancer: updated results of 257 patients in a Japanese multi-institutional study.
      J Thorac Oncol. 2007; 2: S94-100
      ,
      • Shibamoto Y.
      • Hashizume C.
      • Baba F.
      • Ayakawa S.
      • Miyakawa A.
      • Murai T.
      • et al.
      Stereotactic body radiotherapy using a radiobiology-based regimen for stage I non-small-cell lung cancer.
      J Thorac Oncol. 2015; 10: 960-964
      ,
      • Yamamoto T.
      • Kadoya N.
      • Shirata Y.
      • Koto M.
      • Sato K.
      • Matsushita H.
      • et al.
      Impact of tumor attachment to the pleura measured by a pretreatment CT image on outcome of stage I NSCLC treated with stereotactic body radiotherapy.
      Radiat Oncol. 2015; 10: 35
      ,
      • Yoshitake T.
      • Nakamura K.
      • Shioyama Y.
      • Sasaki T.
      • Ohga S.
      • Shinoto M.
      • et al.
      Stereotactic body radiation therapy for primary lung cancers clinically diagnosed without pathological confirmation: a single-institution experience.
      Int J Clin Oncol. 2015; 20: 53-58
      ,
      • Yamashita H.
      • Haga A.
      • Takahashi W.
      • Takenaka R.
      • Imae T.
      • Takenaka S.
      • et al.
      Volumetric modulated arc therapy for lung stereotactic radiation therapy can achieve high local control rates.
      Radiat Oncol. 2014; 9: 243
      ,
      • Inoue T.
      • Katoh N.
      • Onimaru R.
      • Shimizu S.
      • Tsuchiya K.
      • Suzuki R.
      • et al.
      Stereotactic body radiotherapy using gated radiotherapy with real-time tumor-tracking for stage I non-small cell lung cancer.
      Radiat Oncol. 2013; 8: 69
      ,
      • Matsuo Y.
      • Shibuya K.
      • Nagata Y.
      • Takayama K.
      • Norihisa Y.
      • Mizowaki T.
      • et al.
      Prognostic factors in stereotactic body radiotherapy for non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2011; 79: 1104-1111
      ,
      • Shen Z.T.
      • Wu X.H.
      • Li B.
      • Zhu X.X.
      Clinical outcomes of cyberknife stereotactic body radiotherapy for peripheral stage I non-small cell lung cancer.
      Med Oncol. 2015; 32: 55
      ,
      • Wu D.
      • Zhu H.
      • Tang H.
      • Li C.
      • Xu F.
      Clinical analysis of stereotactic body radiation therapy using extracranial gamma knife for patients with mainly bulky inoperable early stage non-small cell lung carcinoma.
      Radiat Oncol. 2011; 6: 84
      ,
      • Ng A.W.
      • Tung S.Y.
      • Wong V.Y.
      Hypofractionated stereotactic radiotherapy for medically inoperable stage I non-small cell lung cancer-report on clinical outcome and dose to critical organs.
      Radiother Oncol. 2008; 87: 24-28
      ,
      • Xia T.
      • Li H.
      • Sun Q.
      • Wang Y.
      • Fan N.
      • Yu Y.
      • et al.
      Promising clinical outcome of stereotactic body radiation therapy for patients with inoperable stage I/II non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2006; 66: 117-125
      ,
      • Kim M.J.
      • Yeo S.G.
      • Kim E.S.
      • Min C.K.
      • Se An P.
      Intensity-modulated stereotactic body radiotherapy for stage I non-small cell lung cancer.
      Oncol Lett. 2013; 5: 840-844
      ,
      • Song S.Y.
      • Choi W.
      • Shin S.S.
      • Lee S.W.
      • Ahn S.D.
      • Kim J.H.
      • et al.
      Fractionated stereotactic body radiation therapy for medically inoperable stage I lung cancer adjacent to central large bronchus.
      Lung Cancer. 2009; 66: 89-93
      ]. These studies were included in the treatment-related toxicity comparison analysis. For 1 retrospective study without toxicity reporting, a similar retrospective study reporting on patients from the same institution treated in the same fashion and in similar time periods was used in the toxicity analysis [
      • Shultz D.B.
      • Trakul N.
      • Abelson J.A.
      • Murphy J.D.
      • Maxim P.G.
      • Le Q.T.
      • et al.
      Imaging features associated with disease progression after stereotactic ablative radiotherapy for stage I non-small-cell lung cancer.
      Clin Lung Cancer. 2014; 15: 294-301
      ,
      • Trakul N.
      • Chang C.N.
      • Harris J.
      • Chapman C.
      • Rao A.
      • Shen J.
      • et al.
      Tumor volume-adpated dosing in stereotactic ablative radiotherapy of lung tumors.
      Int J Radiat Oncol Biol Phys. 2012; 84: 231-237
      ]. Patterns of failure were analyzed based on the information provided in 57 studies, which included 1 phase 3 (only the SBRT data was used), 10 phase 2, 0 phase 1, and 46 retrospective studies [
      • Chang J.
      • Senan S.
      • Paul M.A.
      • Mehran R.J.
      • Louie A.V.
      • Balter P.
      • et al.
      Stereotactic ablative radiotherapy versus lobectomy for operable stage I non-small-cell lung cancer: a pooled analysis of two randomised trials.
      Lancet Oncol. 2015; 16: 630-637
      ,
      • Timmerman R.
      • Paulus R.
      • Galvin J.
      • Michalski J.
      • Straube W.
      • Bradley J.
      • et al.
      Stereotactic body radiation therapy for inoperable early stage lung cancer.
      JAMA. 2010; 303: 1070-1076
      ,
      • Timmerman R.D.
      • Hu C.
      • Michalski J.
      • Straube W.
      • Galvin J.
      • Johnstone D.
      • et al.
      Long-term results of RTOG 0236: a phase II trial of stereotactic body radiation therapy (SBRT) in the treatment of patients with medically inoperable stage I non-small cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2014; 90: S30
      ,
      • Videtic G.M.
      • Hu C.
      • Singh A.K.
      • Chang J.Y.
      • Parker W.
      • Olivier K.R.
      • et al.
      A randomized phase 2 study comparing 2 stereotactic body radiation therapy schedules for medically inoperable patients with stage I peripheral non-small cell lung cancer: NRG Oncology RTOG 0915 (NCCTG N0927).
      Int J Radiat Oncol Biol Phys. 2015; 93: 757-764
      ,
      • Fakiris A.J.
      • McGarry R.C.
      • Yiannoutsos C.T.
      • Papiez L.
      • Williams M.
      • Henderson M.A.
      • et al.
      Stereotactic body radiation therapy for early-stage non-small-cell lung carcinoma: four-year results of a prospective phase II study.
      Int J Radiat Oncol Biol Phys. 2009; 75: 677-682
      ,
      • Baumann P.
      • Nyman J.
      • Hoyer M.
      • Wennberg B.
      • Gagliardi G.
      • Lax I.
      • et al.
      Outcome in a prospective phase II trial of medically inoperable stage I non-small-cell lung cancer patients treated with stereotactic body radiotherapy.
      J Clin Oncol. 2009; 27: 3290-3296
      ,
      • Lindberg K.
      • Nyman J.
      • Källskog V.R.
      • Hoyer M.
      • Lund J.Ǻ.
      • Lax I.
      • et al.
      Long-term results of a prospective phase II trial of medically inoperable stage I NSCLC treated with SBRT – the Nordic experience.
      Acta Oncol. 2015; 54: 1096-1104
      ,
      • Navarro-Martin A.
      • Aso S.
      • Cacicedo J.
      • Arnaiz M.
      • Navarro V.
      • Rosales S.
      • et al.
      Phase II trial of SBRT for stage I NSCLC: survival, local control, and lung function at 36 months.
      J Thorac Oncol. 2016; (In press)
      ,
      • Bral S.
      • Gevaert T.
      • Linthout N.
      • Versmessen H.
      • Collen C.
      • Engels B.
      • et al.
      Prospective, risk-adapted strategy of stereotactic body radiotherapy for early-stage non-small-cell lung cancer: results of a phase II trial.
      Int J Radiat Oncol Biol Phys. 2011; 80: 1343-1349
      ,
      • Ricardi U.
      • Filippi A.R.
      • Guarneri A.
      • Giglioli F.R.
      • Ciammella P.
      • Franco P.
      • et al.
      Stereotactic body radiation therapy for early stage non-small cell lung cancer: results of a prospective trial.
      Lung Cancer. 2010; 68: 72-77
      ,
      • Nagata Y.
      • Hiraoka M.
      • Shibata T.
      • Onishi H.
      • Kokubo M.
      • Karasawa K.
      • et al.
      Prospective trial of stereotactic body radiation therapy for both operable and inoperable T1N0M0 non-small cell lung cancer: Japan Clinical Oncology Group Study JCOG0403.
      Int J Radiat Oncol Biol Phys. 2015; 93: 989-996
      ,
      • Koto M.
      • Takai Y.
      • Ogawa Y.
      • Matsushita H.
      • Takeda K.
      • Takahashi C.
      • et al.
      A phase II study on stereotactic body radiotherapy for stage I non-small cell lung cancer.
      Radiother Oncol. 2007; 85: 429-434
      ,
      • Onishi H.
      • Kuriyama K.
      • Komiyama T.
      • Tanaka S.
      • Sano N.
      • Marino K.
      • et al.
      Clinical outcomes of stereotactic radiotherapy for stage I non-small cell lung cancer using a novel irradiation technique: patient self-controlled breath-hold and beam switching using a combination of linear accelerator and CT scanner.
      Lung Cancer. 2004; 45: 45-55
      ,
      • Taremi M.
      • Hope A.
      • Dahele M.
      • Pearson S.
      • Fung S.
      • Purdie T.
      • et al.
      Stereotactic body radiotherapy for medically inoperable lung cancer: prospective, single-center study of 108 consecutive patients.
      Int J Radiat Oncol Biol Phys. 2012; 82: 967-973
      ,
      • Mak R.H.
      • Hermann G.
      • Lewis J.H.
      • Aerts H.J.W.L.
      • Baldini E.H.
      • Chen A.B.
      • et al.
      Outcomes by tumor histology and KRAS mutation status after lung stereotactic body radiation therapy for early-stage non-small-cell lung cancer.
      Clin Lung Cancer. 2015; 16: 24-32
      ,
      • Ebright M.I.
      • Russo G.A.
      • Gupta A.
      • Subramaniam R.M.
      • Fernando H.C.
      • Kachnic L.A.
      Positron emission tomography combined with diagnostic chest computed tomography enhances detection of regional recurrence after stereotactic body radiation therapy for early stage non-small cell lung cancer.
      J Thorac Cardiovasc Surg. 2013; 145: 709-715
      ,
      • Park H.S.
      • Harder E.M.
      • Mancini B.R.
      • Decker R.H.
      Central versus peripheral tumor location: influence on survival, local control, and toxicity following stereotactic body radiotherapy for primary non-small-cell lung cancer.
      J Thorac Oncol. 2015; 10: 832-837
      ,
      • Spratt D.E.
      • Wu A.J.
      • Adeseye V.
      • Din S.U.
      • Shaikh F.
      • Woo K.M.
      • et al.
      Recurrence patterns and second primary lung cancers after stereotactic body radiation therapy for early-stage non-small-cell lung cancer: implications for surveillance.
      Clin Lung Cancer. 2015; 17: 177-183
      ,
      • Parashar B.
      • Port J.
      • Arora S.
      • Christos P.
      • Trichter S.
      • Nori D.
      • et al.
      Analysis of stereotactic body radiation vs. wedge resection vs. wedge resection plus cesium-131 brachytherapy in early stage lung cancer.
      Brachytherapy. 2015; 14: 648-654
      ,
      • Kelley K.D.
      • Benninghoff D.L.
      • Stein J.S.
      • Li J.Z.
      • Byrnes R.T.
      • Potters L.
      • et al.
      Medically inoperable peripheral lung cancer treated with stereotactic body radiation therapy.
      Radiat Oncol. 2015; 10: 120
      ,
      • Vu C.C.
      • Matthews R.
      • Kim B.
      • Franceschi D.
      • Bilfinger T.V.
      • Moore W.H.
      Prognostic value of metabolic tumor volume and total lesion glycolysis from 18F-FDG PET/CT in patients undergoing stereotactic body radiation therapy for stage I non-small-cell lung cancer.
      Nucl Med Commun. 2013; 34: 959-963
      ,
      • Horne Z.D.
      • Clump D.A.
      • Vargo J.A.
      • Shah S.
      • Beriwal S.
      • Burton S.A.
      • et al.
      Pretreatment SUVmax predicts progression-free survival in early-stage non-small cell lung cancer treated with stereotactic body radiation therapy.
      Radiat Oncol. 2014; 9: 41
      ,
      • Vahdat S.
      • Oermann E.K.
      • Collins S.P.
      • Yu X.
      • Abedalthagafi M.
      • DeBrito P.
      • et al.
      Cyberknife radiosurgery for inoperable stage IA non-small cell lung cancer: 18F-fluorodeoxyglucose positron emission tomography/computed tomography serial tumor response assessment.
      J Hem Oncol. 2010; 3: 6
      ,
      • Dunlap N.E.
      • Larner J.M.
      • Read P.W.
      • Kozower B.D.
      • Lau C.L.
      • Sheng K.
      • et al.
      Size matters: a comparison of T1 and T2 peripheral non-small-cell lung cnacers treated with stereotactic body radiation therapy (SBRT).
      J Thorac Cardiovasc Surg. 2010; 140: 583-589
      ,
      • Brown W.T.
      • Wu X.
      • Fayad F.
      • Fowler J.F.
      • García S.
      • Monterroso M.I.
      • et al.
      Application of robotic stereotactic radiotherapy to peripheral stage I non-small cell lung cancer with curative intent.
      Clin Oncol. 2009; 21: 623-631
      ,
      • Grills I.S.
      • Hope A.J.
      • Guckenberger M.
      • Kestin L.L.
      • Werner-Wasik M.
      • Yan D.
      • et al.
      A collaborative analysis of stereotactic lung radiotherapy outcomes for early-stage non-small-cell lung cancer using daily online cone-beam computed tomography image-guided radiotherapy.
      J Thorac Oncol. 2012; 7: 1382-1393
      ,
      • Burdick M.J.
      • Stephans K.L.
      • Reddy C.A.
      • Djemil T.
      • Srinivas S.M.
      • Videtic G.M.
      Maximum standardized uptake value from staging FDG-PET/CT does not predict treatment outcome for early-stage non-small-cell lung cancer treated with stereotactic body radiotherapy.
      Int J Radiat Oncol Biol Phys. 2010; 78: 1033-1039
      ,
      • Fischer-Valuck B.W.
      • Boggs H.
      • Katz S.
      • Durci M.
      • Acharya S.
      • Rosen L.R.
      Comparison of stereotactic body radiation therapy for biopsy-proven versus radiographically diagnosed early-stage non-small lung cancer: a single-institution experience.
      Tumori. 2015; 10: 287-293
      ,
      • Zhang X.
      • Liu H.
      • Balter P.
      • Allen P.K.
      • Komaki R.
      • Pan T.
      • et al.
      Positron emission tomography for assessing local failure after stereotactic body radiotherapy for non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2012; 83: 1558-1565
      ,
      • Shultz D.B.
      • Trakul N.
      • Abelson J.A.
      • Murphy J.D.
      • Maxim P.G.
      • Le Q.T.
      • et al.
      Imaging features associated with disease progression after stereotactic ablative radiotherapy for stage I non-small-cell lung cancer.
      Clin Lung Cancer. 2014; 15: 294-301
      ,
      • Nath S.K.
      • Sandhu A.P.
      • Kim D.
      • Bharne A.
      • Nobiensky P.D.
      • Lawson J.D.
      • et al.
      Locoregional and distant failure following image-guided stereotactic body radiation for early-stage primary lung cancer.
      Radiother Oncol. 2011; 99: 12-17
      ,
      • Olsen J.R.
      • Robinson C.G.
      • El Naqa I.
      • Creach K.M.
      • Drzymala R.E.
      • Parikh P.J.
      • et al.
      Dose-response for stereotactic body radiotherapy in early-stage non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2011; 81: e299-303
      ,
      • Richardi U.
      • Frezza G.
      • Filippi A.R.
      • Badellino S.
      • Levis M.
      • Navarria P.
      • et al.
      Stereotactic ablative radiotherapy for stage I histologically proven non-small cell lung cancer: an Italian multicenter observational study.
      Lung cancer. 2014; 84: 248-253
      ,
      • Jeppesen S.S.
      • Schytte T.
      • Jensen H.R.
      • Brink C.
      • Hansen O.
      Stereotactic body radiation therapy versus conventional radiation therapy in patients with early stage non-small cell lung cancer: an updated retrospective study on local failure and survival rates.
      Acta Oncol. 2013; 52: 1552-1558
      ,
      • Andratschke N.
      • Zimmermann F.
      • Boehm E.
      • Schill S.
      • Schoenknecht C.
      • Thamm R.
      • et al.
      Stereotactic radiotherapy of histologically proven inoperable stage I non-small cell lung cancer: patterns of failure.
      Radiother Oncol. 2011; 101: 245-249
      ,
      • Kopeck N.
      • Paludan M.
      • Petersen J.
      • Hansen A.T.
      • Grau C.
      • Høyer M.
      Co-morbidity index predicts for mortality after stereotactic body radiotherapy for medically inoperable early-stage non-small cell lung cancer.
      Radiother Oncol. 2009; 93: 402-407
      ,
      • Nyman J.
      • Johansson K.A.
      • Hultén U.
      Stereotactic hypofractionated radiotherapy for stage I non-small cell lung cancer – mature results for medically inoperable patients.
      Lung Cancer. 2006; 51: 97-103
      ,
      • Kastelijn E.A.
      • El Sharouni S.Y.
      • Hofman F.N.
      • Van Putte B.P.
      • Monninkhof E.M.
      • Van Vulpen M.
      • et al.
      Clinical outcomes in early-stage NSCLC treated with stereotactic body radiotherapy versus surgical resection.
      Anticancer Res. 2015; 35: 5607-5614
      ,
      • Peulen H.
      • Belderbos J.
      • Rossi M.
      • Sonke J.J.
      Mid-ventilation based PTV margins in stereotactic body radiotherapy (SBRT): a clinical evaluation.
      Radiother Oncol. 2014; 110: 511-516
      ,
      • Senthi S.
      • Lagerwaard F.J.
      • Haasbeek C.J.A.
      • Slotman B.J.
      • Senan S.
      Patterns of disease recurrence after stereotactic ablative radiotherapy for early stage non-small-cell lung cancer: a retrospective analysis.
      Lancet Oncol. 2012; 13: 802-809
      ,

      Van der Voort van Zyp NC, Prévost JB, Hoogeman MS, Praag J, van der Holt B, Levendag PC, et al. Stereotactic radiotherapy with real-time tumor tracking for non-small cell lung cancer: clinical outcome. 2009; 91: 296 - 300.

      ,
      • Duncker-Rohr V.
      • Nestle U.
      • Momm F.
      • Prokic V.
      • Heinemann F.
      • Mix M.
      • et al.
      Stereotactic ablative radiotherapy for small lung tumors with a moderate dose. Favorable results and low toxicity.
      Strahlenther Onkol. 2013; 189: 33-40
      ,
      • Fritz P.
      • Kraus H.J.
      • Blaschke T.
      • Mühlnickel W.
      • Strauch K.
      • Engel-Riedel W.
      • et al.
      Stereotactic, high single-dose irradiation of stage I non-small cell lung cancer (NSCLC) using four-dimensional CT scans for treatment planning.
      Lung Cancer. 2008; 60: 193-199
      ,
      • Hof H.
      • Muenter M.
      • Oetzel D.
      • Hoess A.
      • Debus J.
      • Herfarth K.
      Stereotactic single-dose radiotherapy (radiosurgery) of early stage nonsmall-cell lung cancer (NSCLC).
      Cancer. 2007; 110: 148-155
      ,
      • Wulf J.
      • Haedinger U.
      • Oppitz U.
      • Thiele W.
      • Mueller G.
      • Flentje M.
      Stereotactic radiotherapy for primary lung cancer and pulmonary metastases: a noninvasive treatment approach in medically inoperable patients.
      Int J Radiat Oncol Biol Phys. 2004; 60: 186-196
      ,
      • Onishi H.
      • Shirato H.
      • Nagata Y.
      • Hiraoka M.
      • Fujino M.
      • Gomi K.
      • et al.
      Hypofractionated stereotactic radiotherapy (HypoFXSRT) for stage I non-small cell lung cancer: updated results of 257 patients in a Japanese multi-institutional study.
      J Thorac Oncol. 2007; 2: S94-100
      ,
      • Tsurugai Y.
      • Kozuka T.
      • Ishizuka N.
      • Oguchi M.
      Relationship between the consolidation to maximum tumor diameter ratio and outcomes following stereotactic body radiotherapy for stage I non-small-cell lung cancer.
      Lung Cancer. 2016; 92: 47-52
      ,
      • Hayashi S.
      • Tanaka H.
      • Hoshi H.
      Imaging characteristics of local recurrences after stereotactic body radiation therapy for stage I non-small cell lung cancer: evaluation of mass-like fibrosis.
      Thorac Cancer. 2015; 6: 186-193
      ,
      • Yamamoto T.
      • Kadoya N.
      • Shirata Y.
      • Koto M.
      • Sato K.
      • Matsushita H.
      • et al.
      Impact of tumor attachment to the pleura measured by a pretreatment CT image on outcome of stage I NSCLC treated with stereotactic body radiotherapy.
      Radiat Oncol. 2015; 10: 35
      ,
      • Yoshitake T.
      • Nakamura K.
      • Shioyama Y.
      • Sasaki T.
      • Ohga S.
      • Shinoto M.
      • et al.
      Stereotactic body radiation therapy for primary lung cancers clinically diagnosed without pathological confirmation: a single-institution experience.
      Int J Clin Oncol. 2015; 20: 53-58
      ,
      • Satoh Y.
      • Onishi H.
      • Nambu A.
      • Araki T.
      Volume-based parameters measured by using FDG PET/CT in patients with stage I NSCLC treated with stereotactic body radiation therapy: prognostic value.
      Radiology. 2014; 270: 275-281
      ,
      • Matsuo Y.
      • Shibuya K.
      • Nagata Y.
      • Takayama K.
      • Norihisa Y.
      • Mizowaki T.
      • et al.
      Prognostic factors in stereotactic body radiotherapy for non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2011; 79: 1104-1111
      ,
      • Shen Z.T.
      • Wu X.H.
      • Li B.
      • Zhu X.X.
      Clinical outcomes of cyberknife stereotactic body radiotherapy for peripheral stage I non-small cell lung cancer.
      Med Oncol. 2015; 32: 55
      ,
      • Wu D.
      • Zhu H.
      • Tang H.
      • Li C.
      • Xu F.
      Clinical analysis of stereotactic body radiation therapy using extracranial gamma knife for patients with mainly bulky inoperable early stage non-small cell lung carcinoma.
      Radiat Oncol. 2011; 6: 84
      ,
      • Ng A.W.
      • Tung S.Y.
      • Wong V.Y.
      Hypofractionated stereotactic radiotherapy for medically inoperable stage I non-small cell lung cancer-report on clinical outcome and dose to critical organs.
      Radiother Oncol. 2008; 87: 24-28
      ,
      • Xia T.
      • Li H.
      • Sun Q.
      • Wang Y.
      • Fan N.
      • Yu Y.
      • et al.
      Promising clinical outcome of stereotactic body radiation therapy for patients with inoperable stage I/II non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2006; 66: 117-125
      ,
      • Kim M.J.
      • Yeo S.G.
      • Kim E.S.
      • Min C.K.
      • Se An P.
      Intensity-modulated stereotactic body radiotherapy for stage I non-small cell lung cancer.
      Oncol Lett. 2013; 5: 840-844
      ,
      • Song S.Y.
      • Choi W.
      • Shin S.S.
      • Lee S.W.
      • Ahn S.D.
      • Kim J.H.
      • et al.
      Fractionated stereotactic body radiation therapy for medically inoperable stage I lung cancer adjacent to central large bronchus.
      Lung Cancer. 2009; 66: 89-93
      ,
      • Baba F.
      • Shibamoto Y.
      • Ogino H.
      • Murata R.
      • Sugie C.
      • Iwata H.
      • et al.
      Clinical outcomes of stereotactic body radiotherapy for stage I non-small cell lung cancer using different doses depending on tumor size.
      Radiat Oncol. 2010; 5: 81
      ]. Among them, 1 retrospective study was not included in the survival outcome or toxicity profile analysis [
      • Baba F.
      • Shibamoto Y.
      • Ogino H.
      • Murata R.
      • Sugie C.
      • Iwata H.
      • et al.
      Clinical outcomes of stereotactic body radiotherapy for stage I non-small cell lung cancer using different doses depending on tumor size.
      Radiat Oncol. 2010; 5: 81
      ]. It was included in the patterns of failure analysis because of a lack of information in a study from the same institution that was used for survival outcome analysis. At last, 8 studies providing adequate clinical information were included in the clinical outcome comparison for T1 vs. T2 NSCLC analysis [
      • Onishi H.
      • Shirato H.
      • Nagata Y.
      • Hiraoka M.
      • Fujino M.
      • Gomi K.
      • et al.
      Stereotactic body radiotherapy (SBRT) for operable stage I non-small-cell lung cancer: can SBRT be comparable to surgery?.
      Int J Radiat Oncol Biol Phys. 2011; 81: 1352-1358
      ,
      • Baumann P.
      • Nyman J.
      • Hoyer M.
      • Wennberg B.
      • Gagliardi G.
      • Lax I.
      • et al.
      Outcome in a prospective phase II trial of medically inoperable stage I non-small-cell lung cancer patients treated with stereotactic body radiotherapy.
      J Clin Oncol. 2009; 27: 3290-3296
      ,
      • Koto M.
      • Takai Y.
      • Ogawa Y.
      • Matsushita H.
      • Takeda K.
      • Takahashi C.
      • et al.
      A phase II study on stereotactic body radiotherapy for stage I non-small cell lung cancer.
      Radiother Oncol. 2007; 85: 429-434
      ,
      • Brown W.T.
      • Wu X.
      • Fayad F.
      • Fowler J.F.
      • García S.
      • Monterroso M.I.
      • et al.
      Application of robotic stereotactic radiotherapy to peripheral stage I non-small cell lung cancer with curative intent.
      Clin Oncol. 2009; 21: 623-631
      ,
      • Guckenberger M.
      • Allgäuer M.
      • Appold S.
      • Dieckmann K.
      • Ernst I.
      • Ganswindt U.
      • et al.
      Safety and efficacy of stereotactic body radiotherapy for stage I non-small-cell lung cancer in routine clinical practice.
      J Thorac Oncol. 2013; 8: 1050-1058
      ,
      • Andratschke N.
      • Zimmermann F.
      • Boehm E.
      • Schill S.
      • Schoenknecht C.
      • Thamm R.
      • et al.
      Stereotactic radiotherapy of histologically proven inoperable stage I non-small cell lung cancer: patterns of failure.
      Radiother Oncol. 2011; 101: 245-249
      ,
      • Xia T.
      • Li H.
      • Sun Q.
      • Wang Y.
      • Fan N.
      • Yu Y.
      • et al.
      Promising clinical outcome of stereotactic body radiation therapy for patients with inoperable stage I/II non-small-cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2006; 66: 117-125
      ,
      • Baba F.
      • Shibamoto Y.
      • Ogino H.
      • Murata R.
      • Sugie C.
      • Iwata H.
      • et al.
      Clinical outcomes of stereotactic body radiotherapy for stage I non-small cell lung cancer using different doses depending on tumor size.
      Radiat Oncol. 2010; 5: 81
      ]. Among them, 1 retrospective study was not included in previous analyses as a study of larger sample size was included instead [
      • Onishi H.
      • Shirato H.
      • Nagata Y.
      • Hiraoka M.
      • Fujino M.
      • Gomi K.
      • et al.
      Stereotactic body radiotherapy (SBRT) for operable stage I non-small-cell lung cancer: can SBRT be comparable to surgery?.
      Int J Radiat Oncol Biol Phys. 2011; 81: 1352-1358
      ,
      • Onishi H.
      • Shirato H.
      • Nagata Y.
      • Hiraoka M.
      • Fujino M.
      • Gomi K.
      • et al.
      Hypofractionated stereotactic radiotherapy (HypoFXSRT) for stage I non-small cell lung cancer: updated results of 257 patients in a Japanese multi-institutional study.
      J Thorac Oncol. 2007; 2: S94-100
      ]. PBT studies included 4 prospective studies (1 phase 2, and 3 phase I/II), and 5 retrospective studies [
      • Bush D.A.
      • Cheek G.
      • Zaheer S.
      • Wallen J.
      • Mirshahidi H.
      • Katerelos A.
      • et al.
      High-dose hypofractionated proton beam radiation therapy is safe and effective for central and peripheral early-stage non-small cell lung cancer: results of a 12-year experience at Loma Linda University Medical Center.
      Int J Radiat Oncol Biol Phys. 2013; 86: 964-968
      ,
      • Miyamoto T.
      • Baba M.
      • Sugane T.
      • Nakajima M.
      • Yashiro T.
      • Kagei K.
      • et al.
      Carbon ion radiotherapy for stage I non-small cell lung cancer using a regimen of four fractions during 1 week.
      J Thorac Oncol. 2007; 2: 916-926
      ,
      • Miyamoto T.
      • Baba M.
      • Yamamoto N.
      • Koto M.
      • Sugawara T.
      • Yashiro T.
      • et al.
      Curative treatment of stage I non-small-cell lung cancer with carbon ion beams using a hypofractionated regimen.
      Int J Radiat Oncol Biol Phys. 2007; 67: 750-758
      ,
      • Karube M.
      • Yamamoto N.
      • Nakajima M.
      • Yamashita H.
      • Nakagawa K.
      • Miyamoto T.
      • et al.
      Single-fraction carbon-ion radiation therapy for patients 80 years of age and older with stage I non-small cell lung cancer.
      Int J Radiat Oncol Biol Phys. 2016; 95: 542-548
      ,
      • Westover K.D.
      • Seco J.
      • Adams J.A.
      • Lanuti M.
      • Choi N.C.
      • Engelsman M.
      • et al.
      Proton SBRT for medically inoperable stage I NSCLC.
      J Thorac Oncol. 2012; 7: 1021-1025
      ,
      • Hatayama Y.
      • Nakamura T.
      • Suzuki M.
      • Azami Y.
      • Ono T.
      • Yabuuchi T.
      • et al.
      Clinical outcomes and prognostic factors of high-dose proton beam therapy for peripheral stage I non-small-cell lung cancer.
      Clin Lung Cancer. 2015; (in press)
      ,
      • Kanemoto A.
      • Okumura T.
      • Ishikawa H.
      • Mizumoto M.
      • Oshiro Y.
      • Kurishima K.
      • et al.
      Outcomes and prognostic factors for recurrence after high-dose proton beam therapy for centrally and peripherally located stage I non-small-cell lung cancer.
      Clin Lung Cancer. 2014; 15: e7-12
      ,
      • Fujii O.
      • Demizu Y.
      • Hashimoto N.
      • Takagi M.
      • Terashima K.
      • Mima M.
      • et al.
      Particle therapy for clinically diagnosed stage I lung cancer: comparison with pathologically proven non-small cell lung cancer.
      Acta Oncol. 2015; 54: 315-321
      ,
      • Fujii O.
      • Demizu Y.
      • Hashimoto N.
      • Araya M.
      • Takagi M.
      • Terashima K.
      • et al.
      A retrospective comparison of proton therapy and carbon ion therapy for stage I non-small cell lung cancer.
      Radiother Oncol. 2013; 109: 32-37
      ]. All were included in the survival outcome and toxicity profile comparison analyses [
      • Bush D.A.
      • Cheek G.
      • Zaheer S.
      • Wallen J.
      • Mirshahidi H.
      • Katerelos A.
      • et al.
      High-dose hypofractionated proton beam radiation therapy is safe and effective for central and peripheral early-stage non-small cell lung cancer: results of a 12-year experience at Loma Linda University Medical Center.
      Int J Radiat Oncol Biol Phys. 2013; 86: 964-968
      ,
      • Miyamoto T.
      • Baba M.
      • Sugane T.
      • Nakajima M.
      • Yashiro T.
      • Kagei K.
      • et al.
      Carbon ion radiotherapy for stage I non-small cell lung cancer using a regimen of four fractions during 1 week.
      J Thorac Oncol. 2007; 2: 916-926