So, they suggest a new molecular classification of SCLC including three different molecular subgroups: RB1 and/or TP53 wild-type SCLCs, STK11 mutated SCLCs, and finally those SCLCs derived from transformation of NSCLC (non-small cell lung cancer) characterized by peculiar driven mutations such as EGFR [72]. Here, RB1 is linked to non-small cell lung carcinoma.