Abstract
From 1976 through 1989, 94 patients with epidermoid carcinoma of the lung without mediastinal nodal involvement were treated with definitive radiation therapy (RT) at Gunma University hospital. All patients were treated with 10 MV X-rays and the mediastinum was treated in 86% of the patients. The total dose ranged from 60 Gy to 80 Gy with once-daily conventional fractionation. The actuarial two and five-year survival rates of the entire group were 44% and 22%, respectively with a median survival time (MST) of 17 months. Patients with a performance status of 0-1 lived longer than those with a status of 2 or more (MST 22.5 versus 12 months; p<0.05). The survival of 60 patients with Stage T2 tumors was better than that of 24 patients with T3 tumors (MST 19 versus 13.5 months; p<0.1). Forty-seven patients with tumors less than 5 cm in diameter had a two-year progression rate of 25%, in comparison with 39% for 47 patients with tumors greater than 5 cm. The survival difference between these two groups was statistically significant (p<0.01). Patients given a total dose of 80 Gy or over had only 20% local progression at the time of the last follow-up, but they had a lower long-term survival rate than those given a total dose of 60-74 Gy because of the development of pulmonary insufficiency after high-dose irradiation. There was no relapse in the field given 40 Gy or more to the mediastinum for prophylaxis in the patients with no evidence of primary progression. The actuarial five-year survival rates for the patients given 40 Gy or more to the mediastinum, and for the patients given less than 40 Gy were 32% and 9%, respectively. There was a statistically significant difference between these two survival curves, (p<0.05). Differences in survival did not depend on age, sex, or location of the primary tumor. These results should provide support for definitive RT to manage patients with medically inoperable or unresectable epidermoid carcinoma of the lung without mediastinal nodal involvement.
