Biomarker Testing Rates in Patients with Advanced Non-Small Cell Lung Cancer Treated in the Community

Introduction: Over the past few years, molecular targeted therapies have been?emerging for the treatment of metastatic non-small cell lung cancer (NSCLC).?Targeted therapy is associated with improved outcomes in patients with identified gene alterations, and national guidelines recommend routine biomarker testing. This study evaluated real-world rates of documented epidermal growth factor receptor (EGFR) mutation and other biomarker testing in patients with advanced NSCLC over time.?Methods: Adult patients with Stage IV NSCLC were identified between January 1, 2012 and May 31, 2017 from the US Oncology Network iKnowMedTM?electronic health records. Patients were examined overall and by histology. Rates of documented EGFR mutation and other biomarker testing were calculated. Multivariable regression analyses were conducted to identify characteristics associated with documented biomarker testing. Results: A total of 14,461 patients were identified: median age was 69.3 years, 52.3% were male, 14.6% were nonsmokers, and 64.7% had non-squamous histology.?EGFR mutation testing rates were 35.5%?overall, with an increase in rates seen over time: 30.0% in 2012 to 44.0% in 2016?(p??0.001).?Anaplastic lymphoma kinase (ALK), c-ros oncogene 1 (ROS1), and programmed death-ligand 1 (PD-L1) mutation testing rates were 32.9%, 5.7%, and 5.7%, respectively. More recent diagnosis year, non-squamous histology, larger practice size, and nonsmoking status were strongly associated with higher documented EGFR and ALK mutation testing rates.?Conclusions: EGFR mutation testing rates steadily increased over time, but remained less than 50%, with lower mutation testing rates reported for ALK, ROS1, and PD-L1, suggesting that opportunities exist to improve education on testing for biomarkers in NSCLC.