Effect of pulmonary function of split-course radiation therapy for carcinoma of the lung.

A group of patients treated with radiation therapy for bronchogenic carcinoma were evaluated with serial pulmonary function testing. The patients were treated with a split-course technique with 60-Cobalt. A total of 30 patients with unresectable carcinoma have been studied. Measurements of vital capacity (V.C.) and forced expiratory volume at one second (F.E.V.1) were made prior to therapy; at the beginning and end of the split; upon completion of therapy; and thereafter at 1, 2, and 6 months post therapy. The percentage changes in V.C. and F.E.V.1 from pretreatment values are plotted against time. A trend to improve throughout the treatment course is suggested by these results. Twelve patients have been studied at six-month follow-up: eight of the patients showed less than a 10% reduction from pretreatment V.C. and F.E.V.1 and had no respiratory impairment; of the other four patients, three had evidence of progression of disease in the thorax.