When analysing the association between haplotypes and OS, we noticed that rs36084323*C-rs7421861*G-rs11568821*T-rs2227981*G-rs10204525*C haplotype of PDCD1 after adjustment for smoking increased the probability of death among NSCLC patients who underwent surgery to about 70% (HR = 1.70; 95% CI = 1.13, 2.57; P = 0.011) in relation to the reference haplotype: rs36084323*C-rs7421861*A-rs11568821*C-rs2227981*A-rs10204525*C (Supplementary Table S18). Here, PDCD1 is linked to non-small cell lung carcinoma.