It was found that RB1 deletion and TP53 mutation were prevalent in patients who developed SCLC transformation, and the risk of SCLC transformation in patients with EGFR-mutated lung adenocarcinoma combined with RB1 deletion and TP53 mutation was 42.8 times higher than that in patients without RB1 deletion and TP53 mutation (13). This evidence concerns the gene EGFR and small cell lung carcinoma.