Unresectable non-oat cell carcinoma of the lung: definitive radiation therapy.

Between 1976 and 1983, 267 patients with non-oat cell carcinoma of the lung were treated with radiation therapy alone. One hundred thirty-four patients had squamous cell carcinoma; 69, large cell carcinoma; and 64, adenocarcinoma. Stage III carcinoma was diagnosed in 87% of the patients. Total radiation dose was less than 45 Gy in 69 patients (low dose group), 45-55 Gy in 161 (middle dose group), and 55-65 Gy in 37 (high dose group); dosage was 180-200 cGy daily, 5 days per week. Minimum follow-up was 3 years (median, 6 years). Tumor control within the radiation fields was achieved in 12%, 43%, and 78% of the low, middle, and high dose groups, respectively. A complete response rate of 13%, 23%, and 35% and an overall response of 43%, 71%, and 86% were seen in the low, middle, and high dose groups, respectively. The 5-year recurrence-free survival rate for all patients was 7% and was dependent on radiation dose and tumor response. This study indicates that tumor control and complete response rates are improved with a radiation dose of 55-65 Gy and that complete responders have improved survival.