Phase II study of carboplatin in non-small cell lung cancer.

Forty four patients with advanced non-small cell lung cancer (NSCLC) were treated with carboplatin (CBDCA; cis-diammine-1, 1-cyclobutane dicarboxylate platinum II) at a dose of 400-450 mg/m2 intravenously every four weeks in a phase II study. Forty three patients were evaluated for response and toxicity. Two patients achieved responses resulting in an overall response rate of 4.7% (95% confidence limits: 0.6-15.8%); one of these had not been treated previously and the other had been treated previously with vinblastine. The durations of their responses were 5 and 7 months, respectively. The response rate in 28 previously untreated patients was 3.6% (1/28; 95% confidence limits: 0.1-18.3%). Myelosuppression was the most commonly found toxicity, and thrombocytopenia especially was dose-limiting. Thrombocytopenia (less than 75,000/mm3) was observed in 12 patients (28%). Leukopenia (less than 3,000/mm3) was observed in 14 patients (33%). No serious infection or bleeding occurred, however. Treatment with 400-450 mg CBDCA/m2 was well tolerated in the good risk patients in this study. Mild to moderate emesis was observed in 28 patients (65%). No renal toxicity, neurotoxicity or ototoxicity was seen. It was demonstrated that CBDCA had little efficacy in NSCLC at the dose and schedule given in the present study.