LCNEC has been segregated into small-cell lung carcinoma (SCLC)-like, characterized by the co-occurrence of TP53 and RB1 mutations, and non-small-cell lung carcinoma (NSCLC)-like, characterized by the lack of TP53/RB1 co-mutations and STK11/KEAP1/KRAS mutations (4, 6). This evidence concerns the gene RB1 and small cell lung carcinoma.