The decades-long search for a viable treatment option in relapsed SCLC led to immunotherapy when the anti-PD-1 monoclonal antibody nivolumab (alone or in combination with ipilimumab) demonstrated activity in relapse/refractory SCLC in the phase 1/2 trial CheckMate-032, with benefit consistent among different subgroups except patients with ECOG performance status 1 [11]. This evidence concerns the gene PDCD1 and small cell lung carcinoma.