The National Cancer Institute of Canada (NCIC) Clinical Trials Group has carried out a phase II study of VP-16 100 mg/m2 daily x 3 and cisplatin 25 mg/m2 daily x 3 in untreated patients with malignant mesothelioma. Twenty-seven eligible patients were entered on the trial and the majority had pleural and/or soft tissue disease. Myelosuppression and gastrointestinal symptoms were the most common toxicities, and were usually mild or moderate in severity. Only 3 partial responses were seen in the 26 patients evaluable (12%). We conclude that the combination of VP-16 and cisplatin when used in this fashion has only minimal activity in mesothelioma.