Radiation exposure of the heart, lung and skin by radiation therapy for breast cancer: A dosimetric comparison between partial breast irradiation using multicatheter brachytherapy and whole breast teletherapy

Lettmaier, Sebastian; Kreppner, Stephan; Lotter, Michael; Walser, Marc; Ott, Oliver J.; Fietkau, Rainer; Strnad, Vratislav

doi:10.1016/j.radonc.2010.07.011

« Previous Next »Radiotherapy & Oncology
Volume 100, Issue 2 , Pages 189-194, August 2011

Radiation exposure of the heart, lung and skin by radiation therapy for breast cancer: A dosimetric comparison between partial breast irradiation using multicatheter brachytherapy and whole breast teletherapy

Sebastian Lettmaier
- Department of Radiation Oncology, University Hospital, Erlangen, Germany
Stephan Kreppner
- Department of Radiation Oncology, University Hospital, Erlangen, Germany
Michael Lotter
- Department of Radiation Oncology, University Hospital, Erlangen, Germany
Marc Walser
- Radiotherapy Centre, Amberg, Germany
Oliver J. Ott
- Department of Radiation Oncology, University Hospital, Erlangen, Germany
Rainer Fietkau
- Department of Radiation Oncology, University Hospital, Erlangen, Germany
Vratislav Strnad
- Department of Radiation Oncology, University Hospital, Erlangen, Germany
- Corresponding author. Address: Department of Radiation Oncology, University Hospital Erlangen, Universitätsstr. 27, 91054 Erlangen, Germany.

Received 19 February 2010; received in revised form 9 July 2010; accepted 9 July 2010. published online 02 August 2010.

Abstract

Background and purpose

Accelerated partial breast irradiation by means of multicatheter brachytherapy shows great promise in the modern treatment of early breast cancer combining high efficacy in preventing tumour recurrence with low levels of toxicity. The present work attempts a dosimetric comparison between this treatment modality and conventional whole breast external beam radiotherapy by looking at differences in risk organ exposure to radiation.

Patients and methods

The planning CT data sets of 16 consecutive patients with left-sided breast cancer who received external beam radiotherapy to the whole breast followed by a boost to the tumour bed using multicatheter interstitial brachytherapy after breast conserving surgery were used to create two independent physical treatment plans – one for an external radiotherapy, one for sole partial breast brachytherapy in each case assuming a total reference dose of 50Gy for each patient. Dose–volume parameters D_0.1cc, D_0.5cc, D_1cc, D_2cc, D_5cc, D_10cc, D_25cc, D_50cc, V₁₀₀, V₉₀, V₅₀, V₁₀, V₅ for the ipsilateral lung, the heart and the adjacent skin were calculated and compared between the two treatment modalities.

Results

All organs at risk showed a substantially lower radiation exposure in the brachytherapy plan. This was most pronounced for the heart with values differing by a factor of four. Although somewhat less marked this was also true for the ipsilateral lung and the adjacent skin with exposure ratios of three and two, respectively.

Conclusions

With the use of multicatheter interstitial brachytherapy substantial reductions in the radiation exposure of risk organs can be achieved in comparison to whole breast external beam radiotherapy. These are likely to translate into profound clinical benefits.

Keywords: Partial breast irradiation, Dosimetry, Whole breast irradiation