Radiotherapy for sinonasal undifferentiated carcinoma.

PURPOSE: To evaluate the long-term effectiveness of radiotherapy (RT) in the treatment of sinonasal undifferentiated carcinoma (SNUC). MATERIALS AND METHODS: The medical records of 23 patients treated with definitive or postoperative RT between 1992 and 2010 at the University of Florida were retrospectively reviewed. Fifteen patients (65%) received primary surgery and postoperative RT. Radiation doses ranged from 59.0 to 74.8 Gy (median, 70.2 Gy). The median follow-up time for all patients was 3.0 years (range, 0.9-19.9), and for living patients was 7.7 years (range, 2.5-19.9). RESULTS: The actuarial 5-year survival outcomes were as follows: progression-free survival, 42%; cause-specific survival, 43%; and overall survival, 32%. Actuarial 5-year disease control rates were as follows: local control (infield or marginal), 74%; local-regional control (excluding leptomeningeal spread), 58%, regional control 78%, freedom from leptomeningeal recurrence, 72%, and distant metastasis-free survival, 73%. Five of the 8 (62.5%) patients treated with definitive RT died with disease, and 6 of the 15 patients (40%) treated with primary surgery and postoperative RT died with disease. Three patients (13%) experienced severe complications including unilateral eye removal, osteoradionecrosis of the maxilla requiring hyperbaric oxygen and surgery, and brain necrosis. One patient died due to an infected bone graft and brain abscess. CONCLUSIONS: A multimodal approach is best when treating SNUC patients. The prognosis for patients treated with definitive RT ± chemotherapy is less promising than for those who receive surgery and postoperative RT ± chemotherapy. Severe complications occur in about 17% of patients due to the high dose of RT alone or combined with surgery required for acceptable disease control.