Abstract 3426: Real-world biomarker testing rates and trends among patients with advanced non-small cell lung cancer in the US

Abstract Background: Broad biomarker profiling before treatment initiation for non-small cell lung cancer (NSCLC) is recommended. Patients may not receive or receive inadequate biomarker testing before treatment initiation. This study assesses rates and trends of biomarker testing in community and academic oncology practices in the US. Methods: A descriptive cohort study was conducted using electronic health records from an NSCLC registry. Patients who initiated NSCLC treatment following diagnosis of advanced NSCLC (stage IIIB/IIIC/IV) from 01/01/2015-12/31/2021 were identified. Patient demographics (age, gender, race, region) along with histology type (squamous/non-squamous) and hospital type (academic/community) were included. The percentage of patients receiving tests for any of the nine biomarkers before and during therapy was calculated and compared. Results: 8, 769 patients were identified with advanced NSCLC; 65. 9% having non-squamous cell carcinoma; 22. 4% having squamous cell carcinoma; 11. 7% unknown. 13. 4% of patients were from academic centers, 78. 7% from community hospitals, 8. 0% unknown. The majority (59%) were 65+ years; 47. 3% were female. Overall, 83. 2% had biomarker testing at some point in treatment; only 66. 3% before treatment initiation. Over time, biomarker testing rates prior to treatment initiation increased (46. 9% in 2015 to 73. 8% in 2021). The use of biomarker testing in non-squamous cell carcinoma was greater than in squamous cell carcinoma. The most frequent biomarker testing before treatment initiation were PD-L1 (52. 2%), EGFR (51. 6%), and ALK (50. 7%), followed by ROS1 (46. 9%), BRAF (39. 5%), and KRAS (34. 1%). Testing rates for the newest biomarkers NTRK, MET, and RET were 20. 4%, 28. 4%, and 28. 0%, respectively. Testing rates were similar between academic centers and community-based hospitals, except for the newest biomarkers, where use in academic settings was greater. Biomarker testing rates were higher among female patients (χ2 P-value0. 001) ; rates by race were similar (χ2 P-value=0. 83). Conclusion: While the use of biomarker testing in advanced NSCLC is growing, 26% of patients remained untested before treatment initiation. Biomarker testing in non-squamous cell carcinoma is higher than in squamous cell carcinoma, in keeping with the guideline emphasis on biomarker testing for that histology type. Results suggest that further dissemination of guideline recommendations to obtain biomarker test results prior to treatment initiation is important to optimize treatment decisions in the NSCLC landscape. Citation Format: Yiyu Chen, Angeline Carlson. Real-world biomarker testing rates and trends among patients with advanced non-small cell lung cancer in the US abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 3426.