Predictive modelling for swallowing dysfunction after primary (chemo)radiation: Results of a prospective observational study

Christianen, Miranda E.M.C.; Schilstra, Cornelis; Beetz, Ivo; Muijs, Christina T.; Chouvalova, Olga; Burlage, Fred R.; Doornaert, Patricia; Koken, Phil W.; Leemans, C. René; Rinkel, Rico N.P.M.; de Bruijn, Marieke J.; de Bock, G.H.; Roodenburg, Jan L.N.; van der Laan, Bernard F.A.M.; Slotman, Ben J.; Verdonck-de Leeuw, Irma M.; Bijl, Hendrik P.; Langendijk, Johannes A.

doi:10.1016/j.radonc.2011.08.009

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Predictive modelling for swallowing dysfunction after primary (chemo)radiation: Results of a prospective observational study

Miranda E.M.C. Christianen
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
Cornelis Schilstra
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
Ivo Beetz
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
Christina T. Muijs
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
Olga Chouvalova
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
Fred R. Burlage
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
Patricia Doornaert
- Department of Radiation Oncology, VU University Medical Center Amsterdam, The Netherlands
Phil W. Koken
- Department of Radiation Oncology, VU University Medical Center Amsterdam, The Netherlands
C. René Leemans
- Department of Otolaryngology-Head and Neck Surgery, VU University Medical Center Amsterdam, The Netherlands
Rico N.P.M. Rinkel
- Department of Otolaryngology-Head and Neck Surgery, VU University Medical Center Amsterdam, The Netherlands
Marieke J. de Bruijn
- Department of Otolaryngology-Head and Neck Surgery, VU University Medical Center Amsterdam, The Netherlands
G.H. de Bock
- Department of Epidemiology, University Medical Center Groningen, The Netherlands
Jan L.N. Roodenburg
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, The Netherlands
Bernard F.A.M. van der Laan
- Department of Otolaryngology-Head and Neck Surgery, University Medical Center Groningen, University of Groningen, The Netherlands
Ben J. Slotman
- Department of Radiation Oncology, VU University Medical Center Amsterdam, The Netherlands
Irma M. Verdonck-de Leeuw
- Department of Otolaryngology-Head and Neck Surgery, VU University Medical Center Amsterdam, The Netherlands
Hendrik P. Bijl
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
Johannes A. Langendijk
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
- Corresponding author. Address: Department of Radiation Oncology, University Medical Center Groningen, P.O. Box 30001, 9300 RB Groningen, The Netherlands.

Received 26 April 2011; received in revised form 26 July 2011; accepted 9 August 2011. published online 12 September 2011.
Corrected Proof

Abstract

Background and purpose

The purpose of this large multicentre prospective cohort study was to identify which dose volume histogram parameters and pre-treatment factors are most important to predict physician-rated and patient-rated radiation-induced swallowing dysfunction (RISD) in order to develop predictive models for RISD after curative (chemo) radiotherapy ((CH) RT).

Material and methods

The study population consisted of 354 consecutive head and neck cancer patients treated with (CH) RT. The primary endpoint was grade 2 or more swallowing dysfunction according to the RTOG/EORTC late radiation morbidity scoring criteria at 6months after (CH) RT. The secondary endpoints were patient-rated swallowing complaints as assessed with the EORTC QLQ-H&N35 questionnaire. To select the most predictive variables a multivariate logistic regression analysis with bootstrapping was used.

Results

At 6months after (CH) RT the bootstrapping procedure revealed that a model based on the mean dose to the superior pharyngeal constrictor muscle (PCM) and mean dose to the supraglottic larynx was most predictive.

For the secondary endpoints different predictive models were found: for problems with swallowing liquids the most predictive factors were the mean dose to the supraglottic larynx and radiation technique (3D-CRT versus IMRT). For problems with swallowing soft food the mean dose to the middle PCM, age (18–65 versus >65years), tumour site (naso/oropharynx versus other sites) and radiation technique (3D-CRT versus IMRT) were the most predictive factors. For problems with swallowing solid food the most predictive factors were the mean dose to the superior PCM, the mean dose to the supraglottic larynx and age (18–65 versus >65years). And for choking when swallowing the V60 of the oesophageal inlet muscle and the mean dose to the supraglottic larynx were the most predictive factors.

Conclusions

Physician-rated and patient-rated RISD in head and neck cancer patients treated with (CH) RT cannot be predicted with univariate relationships between the dose distribution in a single organ at risk and an endpoint. Separate predictive models are needed for different endpoints and factors other than dose volume histogram parameters are important as well.

Keywords: Radiotherapy, Swallowing dysfunction, Head and neck cancer, Normal tissue complication probability models, Nomograms