Validation of the total dysphagia risk score (TDRS) in head and neck cancer patients in a conventional and a partially accelerated radiotherapy scheme

Background and purpose: A risk model, the total dysphagia risk score (TDRS), was developed to predict which patients are most at risk to develop grade >= 2 dysphagia at 6 months following radiotherapy (RT) for head and neck cancer. The purpose of this study was to validate this model at 6 months and to investigate the power at earlier and later time-points. A second aim was to see if this model can be used in a partially accelerated RT regimen.Materials and methods: 164 patients from 3 different centres treated with RT between 2008 and 2014 were included in the current study. Both physician-scored dysphagia and QoL data were prospectively obtained. The TDRS of all patients was correlated with the physician-scored dysphagia and the QoL data. To validate this prediction model, we tested the validity in terms of calibration and discrimination.Results: Partial acceleration had no influence on the TDRS. Regarding physician-scored dysphagia, there was a significant correlation with dysphagia grade at 1, 3, 6 and 9 months. The area-under-the-curve at 1 month was 0.85; at 3 months 0.80; at 6 months 0.85; at 9 months 0.86 and 0.79 at 12 months. Regarding QoL, TDRS correlates with PEG-tube usage at 6 and 12 months.Conclusion: We found significant correlations between TDRS and dysphagia grade >= 2 and PEG-tube usage. (C) 2015 Elsevier Ireland Ltd. All rights reserved.