Multiple endocrine neoplasia, type 2 (MEN 2)

Learn about this rare condition that causes tumors and overproduction of hormones.

Update Date: 09.07.2026

Overview
Symptoms
Causes
Complications
Prevention
Diagnosis
Treatment
Preparing for an appointment

Overview

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. Healthcare professionals can treat the medical issues that the condition may cause.

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

Types

There are two types of MEN 2:

  • MEN 2A. This also is called classical MEN 2A. It causes medullary thyroid cancer. It also causes tumors of the parathyroid glands and adrenal glands that are not cancer.
  • MEN 2B. This type of MEN 2 is rare. It causes medullary thyroid cancer. It also causes tumors on the adrenal gland, on the lips, on the tongue and in the digestive tract that are not cancer. MEN 2B does not cause issues with the parathyroid glands.

Symptoms

Symptoms of MEN 2 depend on the types of tumors it causes. People who have MEN 2B often have bumps on the tongue, lips and eyes. People with MEN 2B also tend to be tall and thin with long arms and legs. Following are symptoms that may be linked to each tumor type.

Medullary thyroid cancer:

  • Lumps in the throat or neck.
  • Trouble breathing or swallowing.
  • Hoarseness.
  • Loose stools.

Parathyroid hyperplasia, also called primary hyperparathyroidism:

  • Muscle and joint pain.
  • Trouble passing stool.
  • Tiredness.
  • Memory issues.
  • Kidney stones.
  • High blood calcium.

Adrenal tumors, also called pheochromocytoma:

  • High blood pressure.
  • Fast heart rate.
  • Anxiety.
  • Headaches.

A thyroid tumor may cause symptoms by pressing on tissues around it or, rarely, by releasing hormones. Some people who have medullary thyroid cancer have no symptoms.

When to see a doctor

If you have any of these symptoms, contact your healthcare professional.

Multiple endocrine neoplasia, type 2B (MEN 2B)

People with MEN 2B have tumors on nerves in the lips, mouth, eyes and digestive tract. They also may have a tumor on the adrenal gland, called pheochromocytoma, and medullary thyroid cancer.

Causes

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

But some people may be the first in their families to have this condition. If you're diagnosed with medullary thyroid cancer or pheochromocytoma, a rare adrenal tumor, talk with your healthcare professional about genetic testing for MEN 2.

Complications

MEN 2 can affect the parathyroid glands, which sit in the neck. The parathyroid glands then put too much calcium into the blood. This is known as primary hyperparathyroidism. The extra calcium in the blood can cause many issues, including weak bones, called osteoporosis, and kidney stones. The extra calcium also causes the need 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. There may be other symptoms if the cancer spreads outside the neck. Finding and treating medullary thyroid cancer early can improve outcomes.

People with MEN 2 also can have a condition called pheochromocytoma. This condition causes tumors on an adrenal gland that are not cancer. The adrenal glands sit at the top of the kidneys. These tumors can release hormones that cause high blood pressure, sweating and other symptoms.

Prevention

There's no way to prevent MEN 2. But genetic testing can show if someone has a changed gene that causes MEN 2. Children of someone who has this changed gene could inherit it and get MEN 2. Parents, sisters and brothers also can have the changed gene, even if they don't have symptoms.

If someone in your family is diagnosed with MEN 2, your healthcare professional is likely to suggest that you and your family members have genetic testing. This can lead to removing the thyroid gland early in life to treat or manage MEN 2. Being screened for parathyroid or adrenal tumors also can help.

Finding conditions that are linked with MEN 2 at an early stage can help prevent serious complications. There's no cure for MEN 2.

If there are no gene changes found in family members, most often they don't need other screening tests. But genetic testing doesn't find all MEN 2 gene changes. If tests don't find MEN 2 in people who may have it, they and their family members may have regular blood and imaging tests over time to check for signs of the condition.

Diagnosis

To diagnose multiple endocrine neoplasia, type 2, also called MEN 2, your healthcare professional does a physical exam and looks at your medical history and family history. You also may have genetic testing to see if you have a gene change that causes MEN 2.

People with MEN 2 need additional testing at the time of diagnosis and typically yearly after diagnosis. Screening on a regular basis for the tumors that MEN 2 can cause is important. Testing can include blood and urine tests and imaging tests, such as:

  • Calcitonin levels in the blood. Calcitonin is a type of thyroid hormone.
  • Blood calcium.
  • Parathyroid hormone levels.
  • Urine or plasma testing for catecholamines and metanephrines. These are adrenal hormones.
  • MRI.
  • CT scan.
  • Ultrasound.

Treatment

Treatment for MEN 2 depends on the tumors it causes and whether they're on the thyroid, parathyroid or adrenal glands. The tumors can lead to other conditions, which can be treated. These conditions and treatments may include:

  • Medullary thyroid cancer. The treatment for thyroid cancer, including cancer that has spread to other parts of the body, is removing the thyroid gland and the lymph nodes around it with surgery. Medicines also can treat cancer that has spread and can't be removed with surgery. Sometimes children with MEN 2 need thyroid surgery.
  • Parathyroid enlargement. The parathyroid glands can get larger and make too much parathyroid hormone. Treatment most often is surgery to remove all or part of the parathyroid glands that are enlarged, while leaving any glands that are not affected.
  • Adrenal tumors. For these types of tumors, your healthcare professional is likely to suggest removing one or both adrenal glands, depending on what CT or MRI images show.

Preparing for an appointment

You may start by seeing your healthcare professional. Or you may be sent to a specialist in conditions that affect the hormones, called an endocrinologist.

Here's some information to help you get ready for your appointment.

What to expect from your doctor

Your healthcare professional is likely to ask you questions, such as:

  • When did your symptoms begin?
  • Do you have symptoms all the time or do they come and go?
  • How bad are your symptoms?
  • What, if anything, seems to make your symptoms better?
  • What, if anything, seems to make your symptoms worse?

What you can do in the meantime

Do not do anything that seems to make your symptoms worse.

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