Phase I study of a carboplatin-etoposide combination in advanced thoracic cancer

We conducted a phase I trial with the combination carboplatin (CBDCA)-etoposide (VP-16) in thoracic cancer. CBDCA, at a starting dose of 300 mg/m2 dl, was associated with a fixed dose of VP-16 (100 mg/m2 dl-3). Escalation of doses was permitted after three patients entered at each dose level without grade IV toxicity. As expected, hematologic toxicity was the limiting factor. Severe myelosuppression (grade IV) occurred in three out of four patients treated at 350 mg/m2. Only three out of 19 patients treated at 325 mg/m2 exhibited a reversible grade IV hematologic toxicity. Other toxicities were mild and acceptable. Among 15 evaluable patients three showed a partial response. Two of the three responders have previously had a progression while receiving cisplatin and etoposide. The recommended dose of carboplatin to be associated with VP-16 (100 mg/m2 dl-3) is thus 325 mg/m2 dl.