In the analyses according to disease stage, marginal differences were also observed between PFS and expression of the ERCC1-XPF complex in LS-SCLC patients (n = 26) (10.8 [95% CI 4.09–17.55] months versus 13.3 [95% CI 7.32–19.31] months; p = 0.06). This evidence concerns the gene ERCC4 and small cell lung carcinoma.