Phase II study of carboplatin in patients with nonresected lung cancer. Japan Cooperative Oncology Group on Lung Cancer.

A multicenter phase II trial of carboplatin, a new platinum analog of cisplatin, was carried out in bronchogenic carcinoma at 17 institutions throughout Japan. Of 139 patients enrolled in this trial, 10 were excluded from analysis as inevaluable and the remaining 129 were judged to be evaluable for response and toxic effects by the Extramural Review Committee. Patients were treated i.v. with either 300 or 400 mg/m2 carboplatin every 4 weeks. Responses and toxic effects were assessed at both dose levels. The overall response rate was 17.8% (23/129), with response rates of 28.4% (19/67) for small-cell disease, 7.1% (2/28) for squamous-cell carcinoma, and 6.9% (2/29) for adenocarcinoma. The most frequent toxic effects were thrombocytopenia and leukopenia, with a platelet count of less than 7 x 10(4) microliters recorded in 60 patients (46.5%) and a WBC count of less than 3,000/microliters recorded in 60 cases (46.5%). Vomiting occurred in 28 patients (21.7%). Renal, aural, and neurotoxicities were not seen. Hydration was not required. Carboplatin was demonstrated to be active against lung cancer, especially against small-cell lung cancer.