Long-term toxicities in 10-year survivors of radiation treatment for head and neck cancer.

OBJECTIVES: To characterize the recognized but poorly understood long-term toxicities of radiation therapy (RT) for head and neck cancer (HNC).

MATERIALS AND METHODS: We retrospectively evaluated patients treated with curative-intent RT for HNC between 1990 and 2005 at a single institution with systematic multidisciplinary follow-up ≥10years. Long-term toxicities of the upper aerodigestive tract were recorded and assigned to two broad categories: pharyngeal-laryngeal and oral cavity toxicity. Kaplan-Meier estimates and Chi-square tests were used for univariable analysis (UVA). Cox model and logistic regression were used for multivariable analysis (MVA).

RESULTS: We identified 112 patients with follow-up ≥10years (median 12.2). The primary tumor sites were pharynx (42%), oral cavity (34%), larynx (13%), and other (11%). Forty-four percent received postoperative RT, 24% had post-RT neck dissection, and 47% received chemotherapy. Twenty-eight (25%) patients developed pharyngeal-laryngeal toxicity, including 23 (21%) requiring permanent G-tube placed at median of 5.6years (0-20.3) post-RT. Fifty-three (47%) developed oral cavity toxicity, including osteoradionecrosis in 25 (22%) at a median of 7.2years (0.5-15.3) post-RT. On MVA, pharyngeal-laryngeal toxicity was significantly associated with chemotherapy (HR 3.24, CI 1.10-9.49) and age (HR 1.04, CI 1.00-1.08); oral cavity toxicity was significantly associated with chemotherapy (OR 4.40, CI 1.51-12.9), oral cavity primary (OR 5.03, CI 1.57-16.1), and age (OR 0.96, CI 0.92-1.00).

CONCLUSION: Among irradiated HNC patients, pharyngeal-laryngeal and oral cavity toxicity commonly occur years after radiation, especially in those treated with chemotherapy. Follow-up for more than five years is essential because these significant problems afflict patients who have been cured.