Radical external beam radiotherapy for 333 squamous carcinomas of the oral cavity — evaluation of late morbidity and a watch policy for the clinically negative neck

Abstract

Background and purpose. The aims of this study were to examine local control/morbidity for all cases and a ‘watch policy’ for the node-negative neck. Patients/Methods. 333 patients with squamous cell carcinoma of the oral cavity were treated with a short radical radiotherapy regime to the primary site and involved lymph node groups at the Christie Hospital, Manchester, between 1980 and 1987. Only 10 of 278 node-negative patients received elective neck node irradiation. Results. Actuarial cancer-free survival and local control rates at 5 years for the whole group were 55% and 61%, respectively. Control at the primary site was adversely related to increasing T-stage, node positivity and bone involvement at presentation. Osteonecrosis was seen in 14 (5.9%) of 237 cases without bone involvement at presentation. Taking all patients, late morbidity (non-healing soft tissue injury or bone necrosis) was seen in 45 patients (13.6%) at a median time of 21 months from treatment. The factors contributing to late morbidity were: (1) bone involvement at presentation, (2) synchronous MTX chemotherapy, (3) the contribution of scattered radiation from elective neck treatment, (4) increasing radiation dose, (5) increasing target volume for doses less than 55 Gy and (6) dental extractions. Eighty-four (31%) patients who were initially node-negative developed disease in the untreated neck during follow-up. Salvage neck dissections controlled neck disease in half of the node-only recurrences ( 21 42 cases). Conclusion. These results have influenced our treatment policy, with lowering of the primary tumour dose in some cases and addition of elective neck irradiation for T2–T4 No patients.