Multiple endocrine neoplasia, type 1 (MEN 1), sometimes called Wermer's syndrome, is a rare disorder that causes tumors in the endocrine glands and parts of the small intestine and stomach. In MEN 1, the endocrine glands — usually the parathyroids, pancreas and pituitary — grow tumors and release excessive amounts of hormones that can lead to disease. However, the tumors are usually noncancerous (benign).

The excess hormones can cause a wide variety of signs and symptoms, such as tiredness, bone pain, fractures and kidney stones, as well as stomach or intestinal ulcers. Although MEN 1 can't be cured, regular testing can detect problems, and doctors can provide treatment as needed.

MEN 1 is an inherited disorder, meaning people who have the gene mutation can pass it on to their children. Each child has a 50 percent chance of inheriting the disorder.


Symptoms of multiple endocrine neoplasia type 1, or MEN 1, include tiredness, bone pain, broken bones, kidney stones, and ulcers in the stomach or intestines. Symptoms are caused by the release of too many hormones in the body.

Multiple endocrine neoplasia, type 1 (MEN 1) care at Mayo Clinic

Nov. 16, 2018
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