Tongue-Out Radiation Therapy for Patients With Head and Neck Cancer Facilitated a Rapid Recovery From Post-Radiation Therapy Dysgeusia by Lowering Oral Tongue Dose.

Abstract

To report the rapid recovery of treatment-related dysgeusia after tongue-out radiation therapy (TORT) for head and neck cancer (HNC). We retrospectively reviewed 14 patients with HNC who completed TORT with 70 Gy for definitive or salvage and 60 to 66 Gy for adjuvant treatment with or without concurrent chemotherapy. Patient-reported quality of taste was evaluated before, at the end of TORT therapy, and periodically 1, 3, and 6 months after TORT therapy using the University of Washington Quality of Life questionnaire version 4, question 9, including options for no-, mild-, and severe dysgeusia and ageusia. Oral cavity (OC) and oral tongue (OT) were contoured following guidelines. A portion of the anteriorly displaced OT outside the mouth was separately contoured as OT_OUT. Statistical analysis was conducted with the χ² and t test. A probability level of P < .05 was considered significant. In 14 TORT plans, the average volume of OC and OT was 105.8 ± 25.3 and 67.6 ± 20.7 cm³, respectively. OT_OUT comprised 20% (13.4 ± 9.1 cm³) of the entire OT volume. Average mean dose (D_MEAN) to OC, OT, and OT_OUT was 25.2 ± 6.9, 26.4 ± 6.8, and 13.3 ± 2.9 Gy, respectively. Before TORT, no-to-mild versus equal or higher than severe dysgeusia (≥ severe dysgeusia) was 86% (n = 12) versus 14% (n = 2) of patients, respectively; 14% (n = 2) versus 86% (n =12) at the end of TORT (P < .01); 57% (n = 8) versus 43% (n = 6) at 1-month post-TORT (P < .01); 79% (n = 11) versus 21% (n = 3) at 3-month post-TORT (P = .23) and 93% (n = 13) versus 7% (n = 1) at 6-month post-TORT (P = .18). TORT displaced OT anteriorly, lowered D_MEAN to OT, especially to OT_OUT, and facilitated rapid regaining of sense of taste at 1-month post-TORT. Patient-reported quality of taste returned to the baseline at 3-month and 6-month post-TORT. Further randomized study to verify clinical advantages with TORT for HNC is warranted.