Extended-duration therapy in advanced non-small-cell lung cancer: promise and pitfalls

For many years, the cornerstone of treatment for non-small-cell lung cancer (NSCLC) has been third-generation platinum-based chemotherapy. Unfortunately, clinical outcomes with the use of this approach have remained poor, with median survival times of only 8-13 months. In an attempt to improve survival, several therapeutic strategies have recently been investigated, including extended-duration chemotherapy. Although historically maintenance chemotherapy in NSCLC has resulted in less-than-optimal outcomes and there has been a recent surge in interest with this treatment modality. This has been in part because of the strategy of the early delivery of a non-cross-resistant agent after platinum chemotherapy, now termed switch maintenance therapy. Results from several recent phase III trials using this strategy are shifting the treatment paradigm of patients with advanced-stage NSCLC. Despite more favorable outcomes demonstrated with this strategy, study designs and reported results have not been without critique. Here, we review all published extended-duration chemotherapy strategies in NSCLC and seek to clarify outstanding issues as they relate to more recent approaches using this strategy.