Derosa et al. performed the largest independent retrospective study by far to assess the effect of antibiotic treatment prior to the first dose of the anti-PD-1/PD-L1 drug in 360 patients with RCC (n = 121) or NSCLC (n = 139).74 Shorter progression-free survival (PFS) and overall survival was observed in RCC patients exposed to antibiotic 30 or 60 d as well as NSCLC patients exposed to antibiotics 30 d before treatment initiation. The gene discussed is PDCD1; the disease is non-small cell lung carcinoma.