Nivolumab and pembrolizumab monotherapy, acting as programmed death protein 1 (PD-1) inhibitors, have demonstrated moderate responses in specific SCLC subgroups in initial studies, such as Keynote-028, Checkmate-032, and Keynote-158 trials, prompting their clinical adoption in later-line treatment of metastatic ES-SCLC [5-7]. This evidence concerns the gene PDCD1 and small cell lung carcinoma.