Quality of life score as a prognosticator for pharyngeal cancer patients treated with radiotherapy

The purpose of this study was to evaluate the prognostic value of quality of life (QOL) scores acquired not only pre-treatment, but also 1 month after treatment for locoregional control (LRC), distant metastasis-free survival (DMFS), and overall survival (OS) in patients with pharyngeal cancer treated using radiotherapy. Data for 102 patients with naso-, oro-, or hypo-pharyngeal cancer treated between December 2008 and September 2017 were retrospectively analyzed. About 90% of the patients were male. The European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30) was used for QOL assessments. Associations between QLQ-C30 scores before and 1 month after treatment and outcomes including LRC, DMFS, and OS were analyzed using Cox proportional hazard models. Median follow-up was 37 months (range, 5-117 months). Three-year LRC, DMFS, and OS rates were 77.8%, 60.0%, and 66.5%, respectively. Pre-treatment emotional functioning and diarrhea at 1 month after treatment were identified as significant predictors of LRC. Pre-treatment global QOL and diarrhea at 1 month after treatment were detected as significant predictors of DMFS. Pre-treatment emotional functioning, pre-treatment appetite loss, and diarrhea at 1 month after treatment were detected as significant predictors of OS. Diarrhea at 1 month after treatment was the most powerful QOL variable for predicting LRC, DMFS and OS. Our study revealed that several QOL scores not only before treatment but also 1 month after treatment correlated with LRC, DMFS and OS. In particular, the diarrhea domain of QOL at 1 month after treatment offered the most powerful prognosticator for pharyngeal cancer patients treated with radiotherapy.