Proton Therapy for Head and Neck Malignancies at Tsukuba

PURPOSE: To evaluate the effectiveness and feasibility of proton therapy for head and neck cancers. PATIENTS AND METHODS: From 1983 to 2000, 33 patients with head and neck malignancies but no history of surgical resection were treated with 250-MeV protons with or without X-ray irradiation. This study retrospectively evaluated local control, survival, and treatment sequelae of these patients. The median total target dose using protons with or without X-rays was 76 Gy (range: 42-99 Gy) and the median proton dose per fraction 2.8 Gy (range: 1.5-6.0 Gy). RESULTS: Overall 5-year survival and local control rates were 44% and 74%, respectively. One (3%) and six patients (18%) suffered from treatment-related acute and late toxicity > grade 3 (RTOG/EORTC acute and late radiation morbidity scoring criteria). One patient with a history of radiotherapy suffered from acute toxicity > grade 3. CONCLUSION: Proton therapy appeared to offer high local control rates with few toxicities relative to conventional radiotherapy. However, late toxicity was seen in areas where large radiation doses had been given.