A multicenter Italian Cooperative Study Group (FONICAP) conducted a prospective, randomized trial comparing cisplatin and etoposide (VP-16) with single-agent etoposide. The national study accrued 216 patients with measurable or evaluable non-small cell lung cancer (NSCLC) with either unresectable stage III, or distant metastasis (stage IV). One hundred patients were evaluable for response in the single-agent arm, and 93 in the two-drug combination arm. The overall response rates for the etoposide group and cisplatin/etoposide (VP-16) group were 7% and 26%, respectively (P less than 0.005). Five patients (5.6%) in the combination arm and 1 (1%) in the single agent arm had a complete response. The overall median survival was 236 days for the two-drug arm and 178 days on the single-drug arm (P = 0.2). Treatment-related toxicity (nausea and vomiting, leukopenia, anemia, hearing-loss, peripheral neuropathy, serum creatinine elevation) was significantly more pronounced in the combined arm. The addition of cisplatin to etoposide gave a small non-statistically significant improvement in terms of performance status and thoracic symptoms.