T3 laryngeal cancer: a retrospective study of the Dutch Head and Neck Oncology Cooperative Group: study design and general results.

511 Patients with T3 N0-3 M0 squamous cell carcinoma of the larynx, treated in the Netherlands from 1975 until 1984, were retrospectively analysed. Four different treatment policies were followed: primary surgery, planned combination of radiotherapy and surgery, primary radical radiotherapy, and selective radiotherapy. General results are presented. Local control rate was 72%. Regional control rate was 90% for clinically N0 patients and 78% for clinically N+ patients. Salvage therapy was overall successful in 38%. Surgical salvage for local radiation failures (with regional relapse) was successful in 69%, and for regional failures (without local relapse) in 46%. Ultimate locoregional control was 78% and, due to 8% distant metastases, 5-year actuarial corrected survival was 70%. Prognosis did not improve over the years. Corrected survival was independently correlated with tumour extension, involvement of neck nodes and treatment strategy. Corrected survival was similar for primary radiotherapy and primary surgery, but significantly better for planned combined therapy. Multiple primary tumours occurred significantly more often in male (19.5%) than in female patients (7.3%) (P = 0.05), the bronchus being most commonly affected. Cumulative actuarial risk for metachronous tumour was 15% after 5 years and 30% after 10 years so prevention and early detection of these second tumours may play the most important role in improving overall survival rates in the future.