What is MTC?
Medullary thyroid cancer (MTC) is a type of cancer that starts in the thyroid. The thyroid is a small, butterfly-shaped gland in the front of your neck, just below your Adam’s apple. It makes hormones that help control how your body works, like how fast your heart beats and how your body uses energy.
Inside the thyroid are special cells called C cells. These cells make a hormone that helps control calcium in your body. When these C cells start growing out of control, they can form a cancer called medullary thyroid cancer. MTC is another name for medullary thyroid carcinoma.
This picture shows how your body keeps the right amount of calcium in your blood. Calcium is important for strong bones, teeth, heart and muscles.
In your neck, you have a gland called the thyroid. Behind it are tiny glands called the parathyroid glands. These glands make special hormones (chemical messengers) that help control calcium levels.
There are two main hormones shown:
🔵 Parathyroid hormone (PTH)
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Released when calcium in the blood is too low.
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It tells:
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🦴 Bones to release calcium into the blood.
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🩺 Kidneys to keep more calcium instead of letting it leave in urine.
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🍎 Intestines to absorb more calcium from food.
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This makes blood calcium go up.
🟡 Calcitonin
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Released when calcium in the blood is too high.
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It tells:
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🦴 Bones to store calcium instead of releasing it.
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🩺 Kidneys to let more calcium leave in pee.
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This makes blood calcium go down.
So basically:
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If calcium is low, your body works to raise it.
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If calcium is high, your body works to lower it.
This helps keep your body balanced and healthy!
How is medullary thyroid cancer (MTC) diagnosed?
Sometimes, a condition called MEN2B is found first. MEN2B is a genetic condition (something passed down in families). Medullary thyroid cancer (MTC) is one of the problems that can happen with MEN2B.
If MEN2B is not found first, MTC may start as a lump in the neck. The tumor in the thyroid can press on the voice box and make your voice sound hoarse. It can also press on the windpipe and make it hard to breathe. Sometimes, MTC stays small for a long time and does not cause any symptoms. But it can spread to other parts of the body, like the lungs, liver, bones, or brain.
Imaging Tests:
Doctors may use special pictures called imaging scans to look at the thyroid. These can include an ultrasound, CT scan, or MRI.
Blood Tests:
Blood test can be drawn to diagnose MEN2b. Other blood tests to diagnose MTC are Calcitonin and CEA.
Biopsy:
The doctor may also take a small sample of tissue from the thyroid using a very thin needle (FNA- Fine needle Apiration). This is called a biopsy. A doctor who studies cells under a microscope (called a pathologist) looks at the sample to see if there are cancer cells and what type they are.
What is Calcitonin?
Calcitonin is a hormone that helps regulate calcium levels in the blood.
Calcitonin is produced by cells in the thyroid gland (parafollicular cells) which are adjacent to cells which make thyroid hormone (follicular cells). Calcitonin travels from the thyroid gland into the blood stream and then to the bones. It acts on bones to oppose bone mineral breakdown and thereby to oppose release (from bone into the blood) of the minerals calcium and phosphorus.
What it does:
Calcitonin lowers calcium levels when they are too high. It acts in opposition to parathyroid hormone, which increases calcium levels.
Testing
A calcitonin test measures the level of calcitonin in the blood. It can be used to help diagnose or monitor conditions like medullary thyroid cancer (MTC) or C-cell hyperplasia, which are rare conditions that cause abnormal growth of C cells in the thyroid.
A hopeful note
Many people with MEN2B live full, happy, and active lives — even if they have medullary thyroid cancer (MTC). MTC is not a death sentence. In fact, many people in our community are living proof of that, and they are willing to share their stories of strength and hope.
Today, doctors are better than ever at finding MEN2B early, especially in babies and young children. When MEN2B is diagnosed very early, doctors can take important steps — including preventive treatment — to greatly reduce the risk of MTC or even stop it from developing.
Early testing and diagnosis of Multiple Endocrine Neoplasia Type 2B (MEN2B) is one of the most powerful ways to protect your health. The sooner it is found, the more options there are and the better the outcomes can be.
Regular check-ups, staying connected with your doctors, and asking questions are strong and proactive ways to care for yourself or your child. Just as important is finding your community. Connecting with other MEN2B families, sharing experiences, and learning together can bring comfort, confidence, and a deep sense of support.
With early care, knowledge, and a strong, supportive community, families facing MEN2B can move forward with hope, courage, and confidence in the future.
How is medullary thyroid cancer (MTC) treated?
MTC is usually treated by removing the thyroid. This surgery is called a thyroidectomy. In certain people with a high risk for MTC, such as people carrying certain gene changes, a thyroidectomy may be performed to prevent cancer.
Besides surgery, sometimes other treatments are also required, including radiation therapy or chemotherapy.
After treatment, your doctor will monitor levels of a tumor marker called CEA and the hormones produced by C cells (Calcitonin) to keep track of how well the treatment is working or if cancer has come back. CEA is a type of tumor marker found in the blood of those with MTC.
Does medullary thyroid cancer (MTC) run in families?
Twenty-five percent of MTC cases run in families. MTC may be passed down when families carry a change in the RET gene that causes a condition called multiple endocrine neoplasia type 2, or MEN2. There are two types of MEN2: MEN2A and MEN2B.
MEN2A: If you have MEN2A, you have a high chance (90%) of getting MTC. You are also at risk (30% to 50%) for getting pheochromocytoma, a cancer of the adrenal glands. MEN2A is rare, affecting 1 in 40,000 people. MEN2A may also be called Sipple syndrome or PTC syndrome.
MEN2B: MEN2B can sometimes be passed from parent to child but most of the time, it isn’t. If you have MEN2B, you have a 100% chance of getting MTC at a very young age. You also have a 50% chance of getting pheochromocytoma at some point in your life. MEN2B is also called Wagenmann–Froboese syndrome or MEN3.