Association between PD-L1 expression with EGFR, ALK, and ROS1 driver oncogene mutations in non-small cell lung cancer

ABSTRACT Background: Driver mutations and immunological expressions have gained importance in recent years for targeted therapies and immunotherapies of nonsmall cell lung cancer (NSCLC). Aims: This study examined the association between PD-L1 expression and ALK , ROS1 , and EGFR driver oncogene mutations in patients with NSCLC. Materials and Methods: A total of 501 NSCLC patients were included for analysis. Immunohistochemistry was performed with a PD-L1 clone 22c3. EGFR mutations were detected by PCR. ALK and ROS1 rearrangement analysis was performed with FISH. Results: There was a highly statistically significant difference between PD-L1 expression and EGFR mutation. PD-L1 expression was higher in the EGFR wild-type than in mutated EGFR ( P = 0.0002). There was no relationship between PD-L1 expression and ALK and ROS1 mutations ( P = 0.8899, P = 0.2512, respectively). PD-L1 expression was higher in nonadenocarcinomas (non-AC) than in adenocarcinomas (AC) ( P = 0.0438). The ALK rearrangement and EGFR mutations were higher in ACs ( P = 0.0073, P = 0.0012, respectively). ALK , ROS1 rearrangements, and EGFR mutations were higher in nonsmokers ( P < 0.05). EGFR mutations were detected more frequently in females than males ( P = 0.001). There was no relationship between gender and ALK , ROS1 , and PD-L1 ( P > 0.05). The prevalence of EGFR , ALK , and ROS1 driver mutations in the Turkish population was 9.3%, 5.3%, and 2.4%, respectively. Conclusions: In conclusion, PD-L1 expression and mutated EGFR status have a highly negative association. PD-L1 expression was higher in EGFR wild-type patients. Therefore, it shows that the opportunity to receive PD-L1-related treatment may be higher in these patients. We think that PD-L1 immunohistochemical evaluation will increase the clinical predictive importance in EGFR wild-type cases.