Topotecan versus observation after cisplatin plus etoposide in extensive-stage small-cell lung cancer: E7593--a phase III trial of the Eastern Cooperative Oncology Group.

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.