MAX and pheochromocytoma: MEN5 is the rarest and newest MEN syndrome identified, and it is related to germline MAX mutations associated with pheochromocytomas, ganglioneuromas, neuroblastomas, pituitary neuroendocrine tumors, and parathyroid adenomas, as well as nonendocrine tumors such as chondrosarcoma and lung adenocarcinoma [19].