EGFR and small cell lung carcinoma: Data implicating RB1 loss as a driver of SCLC transformation is further supported by Offin et al., who found that “triple-positive” patients with EGFR/RB1/TP53 mutations had an at least 6-fold higher risk of SCLC transformation compared to EGFR-mutant lung adenocarcinomas without RB1/TP53 mutations.