Multiple endocrine neoplasia is a rare, inherited endocrine disorder caused by one or more gene mutations. This health condition is marked by endocrine glands either developing tumors or becoming enlarged. As a result, the production of associated hormones is often excessive. Multiple endocrine neoplasia tumors may be benign or malignant.
For your condition to be considered multiple endocrine neoplasia at least two glands must be affected, but not necessarily at the same time. Once determined, your condition may be referred to as type 1 or type 2. You are typed based on genes involved, glands affected, hormones overproduced and symptoms.
Type 1
Multiple endocrine neoplasia type 1 tumors commonly develop in your parathyroid gland, pituitary gland or pancreas. In some, tumors may occur in their thyroid and adrenal glands as well. A tumor in any of these glands can cause an overproduction of hormones and associated symptoms will likely occur over time.
With multiple endocrine neoplasia type 1, the parathyroid gland is almost always over active causing hyperparathyroidism. In this state, the blood calcium is disrupted causing hypercalcemia, which can lead to symptoms of:
- fatigue
- bone pain
- weakness
- hypertension
- bone thinning
- kidney stones
- kidney damage
- nausea, vomiting
All four of your parathyroid glands can be overactive. Treatment largely depends on severity and symptoms. Removal of all or some of your parathyroid glands is the usual method for treating this hormone overload. Should all your glands be removed, daily calcium and vitamin D supplements are necessary to prevent hypocalcemia.
Many with type 1 also develop tumors in the islet cells of the pancreas and pituitary gland. These tumors may or may not produce hormones.
Various types of islet cell tumors can occur with type 1 multiple endocrine neoplasia. One kind produces too much insulin, known as an insulinoma, which can cause hypoglycemia. Another produces too much gastrin, known as gastrinoma, which causes an overproduction of stomach acid. Gastrin producing tumors often lead to peptic ulcers and digestive enzyme interference causing symptoms or stomach problems like:
Sometimes pancreatic tumors are malignant and can metastasize, but tend to be slow growing relative to other pancreatic cancers.
Pituitary gland tumors seen with multiple endocrine neoplasia type 1 can overly produce several different kinds of hormones, for instance:
- growth hormone, leading to acromegaly
- prolactin, causing menstrual irregularity, breast secretion, erectile dysfunction
- corticotropin, resulting in adrenal gland producing too much corticosteroid causing Cushing’s syndrome
In some cases, the tumor can grow to such a size that it interferes with pituitary gland function or press on nearby brain parts causing headaches and vision impairment. And some with type 1 develop tumors or excessive growth in their thyroid and adrenal glands or develop carcinoid tumors and lipomas.
Type 2
Multiple endocrine neoplasia is classified as type 2 when tumors or excessive growth develops in your thyroid, adrenal or parathyroid glands. Again, 2 or all three of these glands must be affected before this health condition is diagnosed. Most with type 2 develop medullary thyroid cancer, while about half develop pheochromocytomas.
Generally, treatment for most type 1 and type 2 tumors is either surgical removal or taking drugs to counter the effects of a hormone imbalance.