TP53 and laryngotracheoesophageal cleft: In support of the role of p53 in activating mTORC1 through Tsc2 regulation, while analyzing our cohort of HW MB, we detected a small subset of tumors (n = 5 of 57) that was characterized by LC/A histology (Figure 3E), in place of the desmoplastic/classic histology expected in this type of MB (Figure 1A).