2726 - Functional, Patient-Reported, and Physician-Graded Gustatory Outcomes in Nasopharyngeal Carcinoma Survivors Following IMRT
Presenter(s)
J. Chow1, K. P. S. Yeung2, J. C. F. Lui1, S. S. W. Tsui1, J. C. K. Yung1, G. T. C. Cheung3, H. P. Y. Wong1, T. K. K. Tse2, K. C. A. Leung1, K. M. Cheung1, K. H. Au1, B. C. Y. Zee4, W. T. Ng5, and J. Cai6; 1Department of Clinical Oncology, Queen Elizabeth Hospital, Hong Kong, China, 2Department of Occupational Therapy, Queen Elizabeth Hospital, Hong Kong, China, 3Department of Oncology, United Christian Hospital, Hong Kong, China, 4Division of Biostatistics, JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China, 5Department of Clinical Oncology, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China, 6Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China
Purpose/Objective(s): Impairment and distortion of taste function is an under-recognized late complication in survivors of nasopharyngeal carcinoma (NPC) who have undergone definitive radiotherapy. Formal studies examining the prevalence and patterns of this issue are limited. This study aims to conduct a comprehensive assessment of gustatory outcomes in long-term NPC survivors by utilizing functional evaluations, patient-reported measures, and physician-graded tools. The relationship between gustatory outcomes, quality of life (QOL), and the radiation dose-volume metrics of the tongue are also investigated.
Materials/Methods: This is a cross-sectional study conducted in two tertiary oncology centers. NPC survivors who underwent definitive intensity-modulated radiotherapy (IMRT) and remained disease-free for at least 3 years were enrolled. Functional gustatory assessment was performed using Burghart taste strips, which contained five taste qualities (sweetness, saltiness, bitterness, sourness, and umami) at four different concentrations. Based on normative data, quality-specific hypogeusia was defined as a domain score of 0–1, while global hypogeusia was indicated by a total score of < 9. Dysgeusia was characterized by incorrect interpretation of taste quality. Patient-reported gustatory outcomes were evaluated using the taste item from EORTC QLQ-H&N35, while QOL was assessed using the FACT-H&N questionnaire. Physician-graded dysgeusia was evaluated according to the CTCAE v6.0. The tongue was retrospectively delineated in all radiotherapy plans for radiation dosimetric analyses.
Results: This study enrolled 128 NPC survivors, with a median follow-up of 7.2 years (range, 5.4 – 10.5 years) post-IMRT. Most participants (93.0%) underwent concomitant chemotherapy. Taste strip assessments revealed that 60 of the 128 participants (46.9%) exhibited global hypogeusia. The prevalence of taste quality-specific hypogeusia was: sweetness (21.1%), saltiness (41.4%), bitterness (39.8%), sourness (34.4%), and umami (64.1%). The respective prevalence of dysgeusia was 11.7%, 22.1%, 9.6%, 25.6%, and 31.3%. According to EORTC QLQ-H&N35, 25.9% of participants reported moderate to severe problems with their sense of taste. The prevalence of CTCAE grades 1 and 2 dysgeusia was 21.9% and 31.3%, respectively. The median mean dose (Dmean) to the tongue was 47.3 Gy (IQR: 44.7 – 49.7 Gy). Tongue Dmean had a negative correlation with patient-reported quality of life as measured by the FACT-H&N questionnaire (Spearman’s correlation coefficient = -0.21, p=0.032). No statistically significant associations were found between tongue dose and functional or physician-graded gustatory outcomes.
Conclusion: Hypogeusia and dysgeusia are highly prevalent among NPC survivors following definitive IMRT. Further refinement of tongue segmentation and the inclusion of other gustatory structures may be necessary to better understand the dose-toxicity relationship of this late complication.