Purpose: To determine the efficacy of topotecan in combination with standard chemotherapy in previously untreated patients with extensive-stage small-cell lung cancer (SCLC), the Eastern Cooperative Oncology Group (ECOG) conducted a phase III trial.

Patients and methods: Eligible patients had measurable or assessable disease and an ECOG performance status of 0 to 2; stable brain metastases were allowed. All patients received four cycles of cisplatin and etoposide every 3 weeks (step 1; PE). Patients with stable or responding disease were then randomized to observation or four cycles of topotecan (1.5 mg/m(2)/d for 5 days, every 3 weeks; step 2). A total of 402 eligible patients were registered to step 1, and 223 eligible patients were registered to step 2 (observation, n = 111; topotecan, n = 112).

Results: Complete and partial response rates to induction PE were 3% and 32%, respectively. A 7% response rate was observed with topotecan (complete response, 2%; partial response, 5%). The median survival time for all 402 eligible patients was 9.6 months. Progression-free survival (PFS) from date of randomization on step 2 was significantly better with topotecan compared with observation (3.6 months v 2.3 months; P <.001). However, overall survival from date of randomization on step 2 was not significantly different between the observation and topotecan arms (8.9 months v 9.3 months; P =.43). Grade 4 neutropenia and thrombocytopenia occurred in 50% and 3%, respectively, of PE patients in step 1 and 60% and 13% of topotecan patients in step 2. Grade 4/5 infection was observed in 4.6% of PE patients and 1.8% of topotecan patients. Grade 3/4 anemia developed in 22% of patients who received topotecan. No difference in quality of life between topotecan and observation was observed at any assessment time or for any of the subscale scores.

Conclusion: Four cycles of PE induction therapy followed by four cycles of topotecan improved PFS but failed to improve overall survival or quality of life in extensive-stage SCLC. Four cycles of standard PE remains an appropriate first-line treatment for extensive-stage SCLC patients with good performance status.