Risk Factors And Causes For A Pheochromocytoma

Multiple Endocrine Neoplasia Type 2

Multiple endocrine neoplasia syndromes are uncommon genetic disorders where numerous endocrine glands in the body form tumors or grow larger abnormally without developing tumors. Multiple endocrine neoplasia type 2 (MEN type 2) specifically involves tumors or excessive growth in the thyroid gland, parathyroid glands, lips, tongue, gastrointestinal tract, and the adrenal glands. This tumor or overgrowth is caused by aberrant additional activation of the affected glands, which is itself a result of a malfunction or mutation of a tumor suppressor gene. This particular gene is located on chromosome 10, and it is called the RET or Rearranged during Transfection gene. Most often, changes in the glands due to MEN type 2 occur slowly over time, but the abnormal growth can take place in more than a single gland at a time. Almost all individuals with multiple endocrine neoplasia type 2 will develop medullary thyroid cancer, and about half of them will develop pheochromocytomas. When abnormal endocrine gland activation occurs in the adrenal glands of individuals with MEN type 2, a pheochromocytoma will likely develop.