RB1 and small cell lung carcinoma: With the exception of some studies on the Rb/p53/p130 mutant mouse model of SCLC (also known as RPR2 or TKO for triple knock‐out) (see below), metastatic programs of the Pten or Crebbp mutant SCLC‐A subtype or the RPM SCLC‐N subtype have not yet been described.