Investigation of clinicopathological and prognostic association of TERT promoter mutation in non-small cell lung cancer in a Turkish population.

Non-small cell lung cancer (NSCLC) is characterized by a complex and heterogeneous molecular basis. Telomerase reverse transcriptase ( TERT ) gene promoter mutations have been implicated in various cancer types. We aimed to investigate the status of TERT promoter region mutations in NSCLCs and determine associations of clinicopathological connections, driver mutations, programmed death-ligand 1 (PD-L1) expression, and overall survival (OS) in the Turkish population. The study included 186 patients diagnosed with NSCLC at a tertiary care center pathology department between 2017 and 2022. TERT promoter mutations were present in 2.7% and associated with old age ( p = 0.015). The levels of PD-L1 expression were higher in TERT mutants ( p = 0.016). TERT mutants had shorter median OS than wild types ( p = 0.006) and TERT mutation was an independent risk factor ( p = 0.004). TERT and EGFR mutations may co-occur and be associated with shorter median OS in patients who continue to receive EGFR treatment ( p < 0.001). TERT promoter mutations were associated with high PD-L1 expression and adverse prognosis in NSCLC. In addition, they may play a major role in patients' poor clinical outcomes during EGFR therapy. In conclusion, TERT may be a significant parameter for future follow-up and treatment selection of NSCLC.