Targeted Therapies in Lung Cancer.

An ongoing research and multiple clinical trials involve new targeted therapies and less aggressive treatment regimens that improve survival in patients with lung cancer. Targeted therapeutic agents are based on the concept of discovering genetic alterations and the signaling pathways altered in cancer and have added significantly to our armamentarium in order to prolong patient survival and minimizing drug toxicity. Among 34 molecularly targeted drugs approved by U.S. Food and Drug Administration (FDA) for treatment of various cancers since 1998 three targeted therapies have been approved for treatment of lung cancer (gefitinib in 2002, erlotinib in 2003, and bevacizumab in 2006).This review focuses on the targeted therapies in lung cancer, the molecular biomarkers that help identify patients that will benefit for these targeted therapies, describes the basic molecular biology principles and selected molecular diagnostic techniques and the pathological features correlated with molecular abnormalities in lung cancer. Lastly, new molecular abnormalities described in lung cancer that are predictive to novel promising targeted agents in various phases of clinical trials are discussed.