BACKGROUND.
Postoperative radiotherapy is commonly used to treat patients with completely resected nonsmall cell lung carcinoma, but its effect on overall survival has not been established.
METHODS.
After undergoing complete surgical resection, 728 patients with nonsmall cell lung carcinoma (221 Stage I, 180 Stage II, and 327 Stage III) were randomized to receive either postoperative radiotherapy at a total dose of 60 gray or observation only . The main end point was overall survival.
RESULTS.
At the reference date, 218 of 355 patients in the control group had died and 262 of 373 in the radiotherapy group had died. Five-year overall survival was 43% for the control group and 30% for the radiotherapy group (P ϭ 0.002, log rank test; relative risk [RR]: 1.33; 95% confidence interval [CI]: 1.11-1.59). This result was not modified by adjustment for potential prognostic factors. The excess mortality rate for the radiotherapy group was due to an excess of intercurrent deaths (P ϭ 0.0001; RR: 3.47; the 5-year intercurrent death rate was 8% for the control group and 31% for the radiotherapy group). Radiotherapy had no significant effect on local recurrence (RR: 0.85; 95% CI: 0.64 -1.14) and no effect on metastasis (RR: 1.06; 95% CI: 0.85-1.31). The rate of non-cancer-related death increased with the dose per fraction delivered.