Consequences of targeted treatments for second-line therapy.

The paradigm for first-line treatment of relapsed or metastatic non-small cell lung cancer (NSCLC) is changing. Large phase III trials demonstrated that, in 2010, we cannot select a therapy without an accurate definition of tumor histology and epidermal growth factor receptor (EGFR) status. Patients harboring an EGFR-activating mutation have a better prognosis and certainly are extremely sensitive to EGFR-tyrosine kinase inhibitors, while other agents, such as bevacizumab or pemetrexed, are more effective and less toxic in patients with non-squamous histology. Moreover, data from large phase III trials demonstrated that maintenance therapy with pemetrexed, docetaxel or erlotinib is an effective strategy against metastatic NSCLC. Overall, the changing paradigm in first-line treatment of NSCLC inevitably is changing the second-line strategy. In addition, the emerging role of maintenance therapy is leading to early use of all agents potentially active in a second- or third-line setting, with the consequence that very few options are available at disease progression. The aim of this article is to discuss the consequences of targeted treatments for second-line therapy in metastatic NSCLC.