Purpose: To evaluate the role of interstitial brachytherapy as an exclusive radiotherapy modality for primary T1-T2 squamous cell carcinomas (SCC) of the velotonsillar area.
Methods and materials: Between 1992 and 2000, 44 patients with T1-T2 SCC of the tonsil (n = 36) and soft palate (n = 8) were treated to the primary with brachytherapy alone (37 patients) or after a limited resection (7 patients). Eight patients had prior external beam radiation therapy (EBRT) for previous head-and-neck carcinoma. Nineteen patients had initial neck dissection. The mean brachytherapy dose was 58.7 Gy, and the mean reference dose rate and Ir-192 linear activity were 58.2 cGy/h and 1.51 mCi/cm respectively.
Results: With a 75-month median follow-up, 1 patient recurred locally. Isolated nodal relapses occurred in 4 patients, none of whom had initial neck dissection, and salvage therapy was successful in 2. Five-year overall and progression-free survival rates were 76% and 68%, respectively. Full-course radiation therapy was possible in 7 of 12 patients who developed a second primary head-and-neck carcinoma. Late toxicity was limited to 6 mild soft-tissue necroses, and was significantly associated with previous surgery to the primary and high linear activity.
Conclusions: Exclusive brachytherapy for T1-T2 velotonsillar carcinomas is safe and effective, and permits definitive reirradiation for a second head-and-neck cancer. Initial neck dissection should be performed for optimal selection for exclusive brachytherapy.