Multiple Endocrine Neoplasia Type 1Symptoms, Doctors, Treatments, Advances & More
Learn About Multiple Endocrine Neoplasia Type 1
Multiple endocrine neoplasia (MEN) type I is a syndrome in which one or more of the endocrine glands are overactive or form a tumor. It is passed down through families.
The endocrine glands most commonly involved are:
- Pancreas (islet cells)
- Parathyroid
- Pituitary
Wermer syndrome; MEN I
MEN I is caused by a change in a gene that carries the code for a protein called menin. The condition causes tumors of various glands to appear in the same person, but not necessarily at the same time.
The disorder may occur at any age, and it affects men and women equally. A family history of this disorder raises your risk.
Symptoms vary from person to person, and depend on which gland is involved. They may include:
- Abdominal pain
- Anxiety
- Black, tarry stools
- Bloated feeling after meals
- Burning, aching, or hunger discomfort in the upper abdomen or lower chest that is relieved by antacids, milk, or food
- Decreased sexual interest
- Fatigue
- Headache
- Lack of menstrual periods (in women)
- Loss of appetite
- Loss of body or facial hair (in men)
- Mental changes or confusion
- Muscle pain
- Nausea and vomiting
- Sensitivity to the cold
- Unintentional weight loss
- Vision problems
- Weakness
Surgery to remove the diseased gland is often the treatment of choice. Medicines such as cabergoline and bromocriptine may be used instead of surgery for pituitary tumors that release the hormone prolactin.
The parathyroid glands, which regulate calcium production, can be removed. However, it is difficult for the body to regulate calcium levels without these glands, so a total parathyroid removal is not done first in most cases.
Medicines are available to decrease the excess stomach acid production caused by some tumors (gastrinomas), and to reduce the risk of ulcers.
Hormone replacement therapy is given when entire glands are removed or do not produce enough hormones.
The Johns Hopkins Hospital
William Simonds is an Endocrinologist practicing medicine in Baltimore, Maryland. Dr. Simonds is rated as an Elite provider by MediFind in the treatment of Multiple Endocrine Neoplasia Type 1. He is also highly rated in 10 other conditions, according to our data. His clinical expertise encompasses Multiple Endocrine Neoplasia Type 1, Multiple Endocrine Neoplasia, Parathyroid Adenoma, Parathyroidectomy, and Thymectomy. Dr. Simonds is board certified in American Board Of Internal Medicine.
Molecular Medicine And Neuroscience
Lee Weinstein is an Endocrinologist practicing medicine in Bethesda, Maryland. Dr. Weinstein is rated as an Elite provider by MediFind in the treatment of Multiple Endocrine Neoplasia Type 1. He is also highly rated in 14 other conditions, according to our data. His clinical expertise encompasses Multiple Endocrine Neoplasia, Multiple Endocrine Neoplasia Type 1, Albright's Hereditary Osteodystrophy, Parathyroidectomy, and Thymectomy.
Kate Lines practices practicing medicine in Oxford, United Kingdom. Ms. Lines is rated as an Elite expert by MediFind in the treatment of Multiple Endocrine Neoplasia Type 1. She is also highly rated in 18 other conditions, according to our data. Her clinical expertise encompasses Multiple Endocrine Neoplasia Type 1, Multiple Endocrine Neoplasia, Pancreatic Islet Cell Tumor, Autosomal Dominant Hypocalcemia, and Parathyroidectomy.
Pituitary and parathyroid tumors are usually noncancerous (benign), but some pancreatic tumors may become cancerous (malignant) and spread to the liver. These can lower life expectancy.
The symptoms of peptic ulcer disease, low blood sugar, excess calcium in the blood, and pituitary dysfunction usually respond well to appropriate treatment.
The tumors can keep coming back. Symptoms and complications depend on which glands are involved. Regular check-ups by your provider are essential.
Contact your provider if you notice symptoms of MEN I or have a family history of this condition.
Screening close relatives of people affected with this disorder is recommended.
Background: Parathyroid disorders are very common in the general population and include disorders of parathyroid excess, deficiency, or defects in parathyroid hormone (PTH) signaling. PTH, the main secretory product of parathyroid glands is responsible for regulation of calcium-phosphate homeostasis.
Summary: Multiple Endocrine Neoplasia type 1 (MEN1) is an autosomal dominant disease with a high degree of penetrance (\>80% of patients). It is caused by the presence of the MEN1 mutation located on chromosome 11q13. The prevalence of this mutation is estimated at approximately 1/30,000. This hereditary syndrome is characterized by the presence of tumours of the endocrine system (adenoma of the parathyroi...
Published Date: January 25, 2026
Published By: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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