Radiation therapy in the management of carcinoma of the lung.

Carcinoma of the lung is the most common cancer in men in the United States and a major cause of death. This is due to the inadequate techniques for screening of high-risk patients and for detection of the tumor in early stages, before distant dissemination occurs. Although some progress has been made in the past, particularly in improving the knowledge of natural history and pathological characteristics of the disease, and there are better indications for surgical treatment and irradiation and the effective use of cytotoxic agents in selected groups of patients, particularly those with small cell undifferentiated carcinoma, the mortality rate is still very high. A great deal of investigation remains to be done in carcinoma of the lung concerning the basic cell kinetics of the tumor and the optimal conditions for the use of surgery, irradiation, chemotherapy or combinations of these agents in the treatment of these patients before survival rates can be substantially improved. Since the most important factor in patient mortality is distant tumor dissemination, it must be stressed that parameters other than survival should be used to evaluate the effectiveness of irradiation, surgery or combinations in the control of local and regional bronchogenic carcinoma. These efforts should be intensified through properly designed clinical trials.