Biomarker guided treatment of advanced non-small cell lung cancer: does feasibility translate to improvements in patient care?

Molecular characterization of tumors has become integral in the management of advanced non-small cell lung cancer (NSCLC) (1). Over the last decade, major evolution in understanding the role of biomarkers has shaped the current management strategies of NSCLC. Molecularly targeted therapies have now become the preferred initial therapy for NSCLC patients with tumors containing epidermal growth factor receptor (EGFR) mutations, as well as translocations of the anaplastic lymphoma kinase (ALK) gene and c-ros oncogene 1 (ROS1) (2-4). These successes have driven the goal to further personalize treatment decisions in NSCLC. Trials such as the Biomarker-integrated Approaches of Targeted Therapy for Lung Cancer Elimination (BATTLE) evaluated the feasibility of repeat tumor biopsy at the time of disease progression in order to direct further treatment, based on tumor molecular profile (5). The BATTLE trial demonstrated an 8-week disease control rate (DCR) of 46%. Biomarker analysis showed a higher DCR in patients with EGFR wild type (WT) and KRAS mutated tumors, randomized to sorafenib (6).