Biomarker Testing, Treatment, and Outcomes in Patients With Advanced/Metastatic Non–Small Cell Lung Cancer Using a Real-World Database

Background: Little is known about the impact of up-front biomarker testing on long-term outcomes in patients with advanced or metastatic 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 retrospective study used an a/mNSCLC database derived from real-world electronic healthcare records. Patients diagnosed with nonsquamous a/mNSCLC who initiated first-line therapy on or after January 1, 2015, were included. We describe the testing of patients for actionable 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. Multivariable Cox proportional hazard modeling was conducted to compare 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 biomarker 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 patients 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 adjusted 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.