Background: Little is known about the impact of up-front biomarker testing on long-term outcomes in patients with advanced or meta-static non-small cell lung cancer (a/mNSCLC). This study compared overall survival (OS) by biomarker testing status and by receipt of guideline-concordant therapy in a large real-world cohort of patients with a/mNSCLC in the United States. Patients and Methods: This ret-rospective study used an a/mNSCLC database derived from real -world electronic healthcare records. Patients diagnosed with nonsqua-mous a/mNSCLC who initiated first-line therapy on or after January 1, 2015, were included. We describe the testing of patients for action-able biomarkers and whether they subsequently received guideline-recommended first-line treatment. OS was defined as the number of months from the initiation of first-line therapy to the date of death or end of follow-up, and was described using Kaplan-Meier analysis. Mul-tivariable Cox proportional hazard modeling was conducted to com-pare OS between groups adjusting for baseline covariates; adjusted hazard ratios (HRs) were reported. Results: A total of 21,572 patients with a median age of 69 years (IQR, 61-76 years) and follow-up of 9.5 months (IQR, 3.5-21.5 months) were included. Among patients in the database, 88% had a record of receiving testing for at least 1 bio-marker at any time, and 69% of these patients received testing before or at the start of first-line treatment. The adjusted hazard of death was 30% higher in patients who never (vs ever) received biomarker testing in the database (HR, 1.30; 95% CI, 1.24-1.37), and 12% higher in pa-tients who did not receive (vs did receive) biomarker testing before or at the start of first-line treatment (HR, 1.12; 95% CI, 1.08-1.16). The ad-justed hazard of death was 25% higher in patients who did not receive guideline-concordant first-line treatment (vs those who did) after having a biomarker-positive disease (HR, 1.25; 95% CI, 1.13-1.40). Conclusions: Findings suggest that receipt of first-line treatment that is concordant with biomarker testing results and treatment guidelines is associated with improved survival outcomes in patients with a/mNSCLC in the United States.
