RB1 and small cell lung carcinoma: A mouse model incorporating expression of a constitutively active form of MYC coincident with Rb and p53 deletion (Rb/p53/Myc or RPM model) shows rapid growth of SCLC tumors that are highly metastatic and metastasize within weeks of initiation (Mollaoglu et al, 2017; Dammert et al, 2019).