NEUROD1 and prostate adenocarcinoma: Taken together, these insights on ASCL1 versus NEUROD1 expression within NEPC and SYP expression in PRAD argue for a standardized IHC panel–based approach using ASCL1, NEUROD1, INSM1 and SYP, in conjunction with histomorphological assessment, to add greater precision to the diagnosis and treatment of NEPC.