For the TNFSF15–638A > G polymorphism, we found that GG genotype carriers had a significantly elevated risk for developing SCLC (OR = 1.84, 95%CI = 1.13–2.99), but not for developing NSCLC (OR = 1.11, 95%CI = 0.74–1.67), in comparison to those with AA genotype. This evidence concerns the gene TNFSF15 and small cell lung carcinoma.