Multiple endocrine neoplasia, type 2, also called MEN 2, is a rare condition. It causes tumors in the thyroid and parathyroid glands, adrenal glands, lips, mouth, eyes and digestive tract. Genetic testing can find the changed gene that causes MEN 2. Health care providers can treat the health issues that gene may cause.

MEN 2 is an inherited disorder. This means people who have the changed gene can pass it on to their children. Each child has a 50% chance of getting the disorder.


There are two types of MEN 2:

  • MEN 2A. This also is known as classical MEN 2A or Sipple syndrome. It causes medullary thyroid cancer and noncancerous tumors of the parathyroid glands and adrenal glands.
  • MEN 2B. This type of MEN 2 is rare. It causes medullary thyroid cancer, noncancerous tumors of the adrenal gland, and noncancerous tumors on the lips, on the tongue and in the digestive tract. MEN 2B does not cause problems with the parathyroid glands.


Symptoms of MEN 2 depend on the type of tumor. People who have MEN 2B have a unique appearance. They may have bumps on the tongue, lips and eyes. They tend to be tall and thin with long arms and legs. Following are symptoms that may be related to each tumor type.

Medullary thyroid cancer:

  • Lumps in the throat or neck
  • Trouble breathing or swallowing
  • Hoarseness
  • Diarrhea

Parathyroid hyperplasia, also known as primary hyperparathyroidism:

  • Muscle and joint pain
  • Constipation
  • Fatigue
  • Memory problems
  • Kidney stones

Adrenal tumors, also known as pheochromocytoma:

  • High blood pressure
  • Rapid heart rate
  • Anxiety
  • Headaches

Symptoms may be caused by a thyroid tumor pressing on tissues around it or by the release of too many hormones in the body. Some people who have medullary thyroid cancer may have no symptoms.

When to see a doctor

If you're having any of these symptoms, contact your health care provider.


MEN 2 is an inherited condition. This means someone who has a changed gene that can cause MEN 2 can pass that gene on to their children.

Many people also may be the first person in their families to have this disorder. People diagnosed with medullary thyroid cancer are screened regularly for MEN 2.


MEN 2 can cause the parathyroid glands to put too much calcium into the blood. This is known as primary hyperparathyroidism. The parathyroid glands are located in your neck. The extra calcium in the blood can cause many issues, including weak bones, called osteoporosis, kidney stones and having to urinate a lot. Medullary thyroid cancer shows up as a lump on the thyroid or neck. It can be hard to swallow when the tumor is large or other symptoms if the cancer spreads outside the neck.

People with MEN 2 also can have a condition called pheochromocytoma. This condition causes noncancerous tumors on an adrenal gland. The adrenal glands are located at the top of the kidneys. These tumors can release hormones that cause high blood pressure, sweating and other symptoms.


Genetic testing is used to find out if someone has a changed gene that causes MEN 2. Children of someone who has this changed gene could inherit it and develop MEN 2. Parents and siblings also could have the changed gene even if they don't have symptoms.

If someone in your family is diagnosed with MEN 2, your health care provider will likely recommend you and your family members have genetic testing. This is because MEN 2 can be treated or managed by removing the thyroid gland early in life. Being screened for parathyroid or adrenal tumors also can help.

If no gene changes are found in family members, usually no other screening tests are needed. However, genetic testing doesn't find all MEN 2 gene changes. If MEN 2 isn't found in people who may have it, they and their family members will have regular blood and imaging tests over time to check for signs of the disease.

Multiple endocrine neoplasia, type 2 (MEN 2) care at Mayo Clinic

Nov. 22, 2022
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