Time Course and Determinants of Acute Dysgeusia in Patients Receiving Head and Neck Radiation Therapy

Background: Dysgeusia is a common toxicity experienced by head and neck cancer (HNC) patients receiving radiation therapy (RT).In this study, we assessed the timescale of onset, progression, and recovery of dysgeusia using an objective measure. Methods:Patients receiving RT for HNC to 50 Gy were included in this prospective observational study.The Waterless Empirical Taste Test (WETT) was used to objectively measure dysgeusia for the 5 basic tastes: sweet, sour, salty, bitter, and umami.Patients were assessed at baseline (pre-RT), 2-and 4weeks mid-treatment, end of treatment (EOT), and 12-weeks post-RT.Changes in scores at different time points relative to baseline scores were computed.The significance of trends over time was tested using linear regression.Associations of taste scores with clinical and dosimetric variables were tested using Pearson correlation.Results: Of the 50 patients who underwent baseline taste testing, 32 completed 12-week post-RT follow-up assessments.The most common primary tumor site was oropharynx (66%).The median WETT scores were 20.7 at baseline, 16.2 at 2 weeks, 17.7 at 4 weeks, 17.1 at EOT, and 19 at follow-up.Baseline and EOT comparisons revealed a decline in total score (-17.3%), with highest relative changes in umami (-62.5%) and salty (-30.9%).The relative total score change between baseline and follow-up was -8.2% (p=0.011),demonstrating a slight improvement versus EOT, with umami (-50%) and salty (-9.5%) remaining most affected.Pearson correlations showed a moderately strong association between the EOT relative change and mean tongue dose (r: -0.62; p<0.003), and oral cavity mean dose (r: -0.58; p=0.005). Conclusion:This study confirms significant alterations in taste perception in HNC patients during/after RT.Taste changes correlated with mean tongue and oral cavity doses.Future studies and longer followup are warranted to define dose-response relationships in dysgeusia.