Characterizing advanced or metastatic adenocarcinoma of lung— one step closer?

First-line treatment of metastatic non-small-cell lung cancer (NSCLC) has been evolving. Standard treatment of platinum-based combination chemotherapy has yielded an overall survival (OS) of 10 months (1). With the advent of tyrosine kinase inhibitor (TKI) targeting mutant epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK), OS of over 16 months is possible (2,3). However, only less than a half of patients are eligible for targeted therapy. The prevalence of EGFR mutations in lung adenocarcinoma ranges from 12% in non-Asian cohorts to 44.1% in Southeast-Asian cohorts, and ALK mutations at around 5% regardless of ethnicity (4-7). Among them, 6.6% are known to carry other concurrent gene mutations that may hamper efficacy of targeted therapy (8). There is a significant unmet need in identification of additional targetable mechanisms that will improve outcomes in patients with NSCLC.