LAUSR

ABSTRACT Background A meta-analysis method was used to investigate the prognostic value of CD8+ tumor-infiltrating lymphocytes (TILs) in non-small cell lung cancer (NSCLC) patients treated with PD-1/PD-L1 inhibitors. Methods A database search of PubMed, Embase, Web of Science and Cochrane Library up until 7 February, 2023. A clinical study on the relationship between CD8+ TILs and PD-1/PD-L1 inhibitors in the therapeutics of NSCLC. RevMan 5.3 and StataMP 17.0 software were used for meta-analysis. The outcome indicators incorporated overall survival (OS), progression-free survival (PFS) and objective response rate (ORR). Results Nineteen articles with 1488 patients were included. The analysis results showed that high CD8+ TILs were associated with better OS (HR = 0.60, 95% CI: 0.46–0.77; P < 0.0001), PFS (HR = 0.68, 95% CI: 0.53–0.88; P = 0.003) and ORR (OR = 2.26, 95% CI: 1.52–3.36; P < 0.0001) in NSCLC patients treated with PD-1/PD-L1 inhibitors. Subgroup analysis indicated that patients with high CD8+ TILs had good clinical prognostic benefits whether the location of CD8+ TILs was intratumoral or stromal, and compared with East Asian, high CD8+ TILs in Caucasians showed a better prognosis. High CD8+ TILs in peripheral blood did not improve OS (HR = 0.83, 95% CI: 0.69–1.01; P = 0.06) and PFS (HR = 0.93, 95% CI: 0.61–1.14; P = 0.76) in NSCLC patients receiving PD-1/PD-L1 inhibitors. Conclusion In spite of the location of CD8+ TILs, high densities of CD8+ TILs were predictive of treatment outcomes in NSCLC patients treated with PD-1/PD-L1 inhibitors. However, high CD8+ TILs in peripheral blood had no predictive effect.