Phase II trial of cisplatin/etoposide and concurrent radiotherapy followed by paclitaxel/carboplatin consolidation for limited small-cell lung cancer: Southwest Oncology Group 9713

Purpose: Limited small-cell lung cancer (LSCLC) is characterized by a high initial response rate to chemoradiotherapy, but local or systemic relapse occurs in the majority of patients. Previous Southwest Oncology Group trials in LSCLC have utilized cisplatin and etoposide (PE) delivered concurrently with thoracic radiotherapy followed by two consolidation cycles. Newer chemotherapy regimens such as paclitaxel and carboplatin are active in small-cell lung cancer and hold the promise of improving both local and systemic control. S9713 evaluated the substitution of paclitaxel and carboplatin for PE consolidation in LSCLC. Patients and Methods: Between July 1998 and August 1999, 96 patients were accrued from 43 institutions. Eighty-nine patients were eligible; 87 were assessable for survival and response. Treatment consisted of cisplatin 50 mg/m² on days 1, 8, 29, and 36, and etoposide 50 mg/m² on days 1 to 5 and days 29 to 33, with concurrent radiotherapy of 61 Gy beginning on day 1. Consolidation therapy was carboplatin (area under the curve = 6) and paclitaxel 200 mg/m², both drugs administered on day 1 of a 21 day cycle for three cycles. Results: The response rate was 86% (complete response, 33%; partial response, 53%). Median overall survival was 17 months (95% CI, 12.7 to 19.0). One- and 2-year overall survivals were 61% and 33%, respectively. Median progression-free survival (PFS) was 9 months, 1-year PFS was 40%, and 2-year PFS was 21%. Conclusion: Consolidation therapy with paclitaxel and carboplatin in LSCLC resulted in an outcome similar to that seen in prior Southwest Oncology Group trials. This study and others which have tested paclitaxel in small-cell lung cancer dampens enthusiasm for this agent in the primary management of LSCLC.