Forty patients with limited-stage small cell carcinoma of the lung were prospectively evaluated for adjuvant surgery after intensive chemotherapy to determine resectability. All patients giving informed consent and having a Karnofsky performance status greater than or equal to 50% were included in the study, which ran from May, 1980, to September, 1982. Ages ranged from 40 to 70 years (median, 59 years). One patient was lost to follow-up. Thirty-nine patients were evaluated for operation 9 to 15 weeks after diagnosis and after having received two to four cycles of chemotherapy intravenously every 3 weeks (cyclophosphamide, 1,000 mg/m2; doxorubicin, 50 mg/m2; vincristine, 1 mg/m2; VP-16, 300 mg/m2). Two patients had clinical Stage I tumors; 12 patients, Stage II; and 25 patients, Stage III. At the time of reevaluation there were 13 (33%) complete responders, 21 (54%) partial responders, and 5 (13%) with stable disease. Eleven (28%) of the 39 patients underwent thoracotomy using standard resection criteria for non-small cell carcinoma. Eight of these 11 had resectable lesions (2, Stage I; 3, Stage II; 3, Stage III); five pneumonectomies and three lobectomies were performed. Tumor was present in six of eight specimens. Twenty-eight patients were not candidates for operation for various reasons: poor pulmonary function, 5; unresectable tumors, 10; refusal, 6; very poor medical condition, 6; and primary site not identified, 1. Median survival for complete responders was 17 months and for partial responders, 11 months. We have prospectively identified suitable candidates for adjuvant surgery among the total group (denominator population) of patients with limited-stage small cell carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)