RET and pheochromocytoma: Genetic syndromes of pheochromocytoma include multiple endocrine neoplasia type 2 (MEN2A and 2B), neurofibromatosis type 1 (NF1), the pheochromocytoma-paraganglioma syndrome (mutation of the SDHB or SDHD genes), and von Hippel-Lindau syndrome (VHL).