Site Map

Multiple endocrine neoplasia (MEN) I

Wermer syndrome; MEN I

Multiple endocrine neoplasia (MEN) type I is a disease in which one or more of the endocrine glands are overactive or forms a tumor. It is passed down through families.

Endocrine glands most commonly involved include:

Images

Endocrine glands

Causes

MEN I is caused by a defect 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

Symptoms vary from person to person, and depend on which gland is involved. They may include:

Exams and Tests

The health care provider will perform a physical exam and ask questions about your medical history and symptoms. The following tests may be done:

Treatment

Surgery to remove the diseased gland is often the treatment of choice. A medicine called bromocriptine may be used instead of surgery for pituitary tumors that release the hormone prolactin.

The parathyroid glands, which control 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.

Medicine is 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.

Outlook (Prognosis)

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.

Possible Complications

The tumors can keep coming back. Symptoms and complications depend on which glands are involved. Regular check-ups by your provider are essential.

When to Contact a Medical Professional

Contact your provider if you notice symptoms of MEN I or have a family history of this condition.

Prevention

Screening close relatives of people affected with this disorder is recommended.

Related Information

Peptic ulcer
Low blood sugar
Kidney stones
Pituitary tumor
Zollinger-Ellison syndrome
Parathyroid cancer

References

National Comprehensive Cancer Network website. Clinical practice guidelines in oncology (NCCN guidelines): neuroendocrine and adrenal tumors. Version 1.2022. www.nccn.org/professionals/physician_gls/pdf/neuroendocrine.pdf. Updated May 23, 2022. Accessed August 23, 2022.

Newey PJ, Thakker RV. Multiple endocrine neoplasia. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 42.

Nieman LK, Spiegel AM. Polyglandular disorders. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 218.

Thakker RV. Multiple endocrine neoplasia type 1. In: Jameson JL, De Groot LJ, de Kretser DM, et al, eds. Endocrinology: Adult and Pediatric. 7th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 148.

BACK TO TOP

Review Date: 1/25/2022  

Reviewed By: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

ADAM Quality Logo
Health Content Provider
06/01/2025

A.D.A.M., Inc. is accredited by URAC, for Health Content Provider (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics. This site complied with the HONcode standard for trustworthy health information from 1995 to 2022, after which HON (Health On the Net, a not-for-profit organization that promoted transparent and reliable health information online) was discontinued.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2024 A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.