Phase II study of oral etoposide maintenance for patients with extensive stage small cell lung cancer who have responded to the induction on an EP regimen

Abstract

Background: Maintenance therapy for extensive stage small cell lung cancer (ES-SCLC) is still under debate. Many new agents fail during the maintenance course. As an active agent for SCLC, oral etoposide is worth being re-evaluated. Methods: This phase II study was performed to evaluate the toxicity/efficacy of the maintenance of patients with oral etoposide with ES-SCLC responding (complete remission [CR] + partial remission [PR]) to the induction of four cycles of etoposide plus cisplatin (EP) chemotherapy. Maintenance therapy with oral etoposide (50mg/m2, day 1-14, repeated every 21 days until disease progression or unacceptable toxicity occurs) was administered. The primary endpoints were grade 3 and 4 toxicities and progression free survival (PFS). Results: Fifty-four patients with ES-SCLC received standard EP regimens as induction therapy; 31 responding patients were administered oral etoposide as the maintenance treatment. The most common hematological and non-hematological toxicity of the maintenance course was neutropenia and fatigue, respectively. Median PFS was nine months (95% confidence interval (CI): 8.33∼9.67 months), median overall survival (OS) was 14 months (95% CI: 11.58∼16.42 months). Significantly better PFS and OS were seen in patients responding to the induction EP chemotherapy. Conclusions: Oral etoposide maintenance is safe and effective for patients with ES-SCLC who responded to the induction of EP chemotherapy. Significant survival benefit was revealed in patients completely responding to an EP regimen. Further randomized control study is warranted. © 2012 Tianjin Lung Cancer Institute and Wiley Publishing Asia Pty Ltd.