The relationship between tumor response and survival following radiotherapy for carcinoma of the bronchus.

Tumor response was closely observed in a randomized controlled trial of a radiosensitizing drug in the radiotherapy of carcinoma of the bronchus. The persistence of tumor cells in the sputum after treatment and the degree of regression measured radiologically at two months did not correlate with the subsequent course. However, total regression of tumor and time to regrowth both assessed radiologically showed a highly significant correlation with survival (P less than 0.0005).