A recent paper proposed a new molecular classification of LCNEC: type I with STK11/KEAP1 alterations, but with an NE phenotype, high expression of ASCL1 and DLL3, and downregulation of NOTCH pathway, as in the SCLC classical subtype; type II characterized by RB1 alterations, but a predominant non-NE phenotype (with low expression of chromogranin A and synaptophysin), high levels of REST and NOTCH, and immune cell response activation more responsive to NSCLC type therapy (18). Here, RB1 is linked to small cell lung carcinoma.