Abstract 454: The landscape of PD-L1 expression in lung cancer harboring driver oncogene mutations except EGFR mutations

Abstract

Abstract Background: Results from previous studies indicated that lung cancer patients harboring EGFR sensitizing mutations may receive unfavorable outcomes from immunotherapy. The present study aims to investigate the landscape of PD-L1 expression in lung cancer harboring driver oncogene mutations except EGFR mutations. Methods: Tissue samples were subjected to NGS in a College of American Pathologists-certified and Clinical Laboratory Improvement Amendments-accredited lab for driver oncogene mutations and PD-L1 expression. Results: A total of 22143 lung cancer patients were selected, there are 2120 patients have the driver oncogene mutation, including 1115 (5.04%) ALK positive cases,498 (2.25%) MET positive cases,239(1.08%) RET positive cases,182(0.82%) BRAF positive cases, 72 (0.33%) ROS1 positive cases and 14 (0.03%) NTRK positive cases. Among all the driver oncogene mutation patients, 481 patients have been collected tumor tissue, and the PD-L1 expression have been tested by FDA-approved 22C3 antibodies. Among all the driver oncogene mutation cases assessed PD-L1 expression (n=481), low PD-L1 expression levels (<1%) were 33.3% (n=160), PD-L1 expression level of 1%-49% accounted for 38.3% (n=184), PD-L1 expression level of 50%-79% accounted for 19.5% (n=94), PD-L1 expression level of 80%-89% accounted for 4.2% (n=20), and PD-L1 expression level higher than 90% accounted for 4.8% (n=23). Conclusion: Our study supported that NSCLC patients harboring sensitizing oncogenic mutations may potentially benefit from anti-PD-1/L1 especially for those with positive indicators of immunotherapy with strong positive PD-L1 expression. Citation Format: Ningbo Liu, Fuyu Gong. The landscape of PD-L1 expression in lung cancer harboring driver oncogene mutations except EGFR mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 454.