The use of biomarkers in the treatment of non-small cell lung cancer

Over the last fifteen years, significant advances have been made in understanding the mechanisms and pathways that drive tumor growth in patients with non-small cell lung cancer (NSCLC). Molecular testing has become routine, and results directly impact clinical decision-making. The discovery of oncogenic driver mutations within the EGFR and ALK genes and their role as biomarkers that predict response to tyrosine kinase inhibitors (TKIs) has opened the door for precision medicine in which treatment decisions are based on the individual patient's tumor characteristics rather than histology alone. Unfortunately, most patients do not currently benefit from this approach. Research efforts are ongoing to identify additional driver mutations, effective targeted therapies, as well as biomarkers to better predict response to chemotherapies and immunotherapies. This review will focus on the evolving role of biomarkers in the treatment of lung cancer and progress towards making precision medicine a reality for all patients.