Pheochromocytoma - Cause

Cause

Up to 25% of pheochromocytomas may be familial. Mutations of the genes VHL, RET, NF1 (Gene 17 Neurofibromatosis type 1), SDHB and SDHD are all known to cause familial pheochromocytoma/extra-adrenal paraganglioma.

Pheochromocytoma is a tumor of the multiple endocrine neoplasia syndrome, type IIA and type IIB (also known as MEN IIA and MEN IIB, respectively). The other component neoplasms of that syndrome include parathyroid adenomas, and medullary thyroid cancer. Mutations in the autosomal RET proto-oncogene drives these malignancies . Common mutations in the RET oncogene may also account for medullary sponge kidney as well.

Pheochromocytoma linked to MEN II can be caused by RET oncogene mutations. Both syndromes are characterized by pheochromocytoma as well as thyroid cancer (thyroid medullary carcinoma). MEN IIA also presents with hyperparathyroidism, while MEN IIB also presents with mucosal neuroma. It is now postulated that Abraham Lincoln suffered from MEN IIB, rather than Marfan's syndrome as previously thought, though this is uncertain.

Pheochromocytoma is also associated with neurofibromatosis.