Thyroid Cancer

What is thyroid cancer?

Thyroid cancer is a cancer that starts in the thyroid gland. To understand thyroid cancer, it helps to know about the normal structure and function of the thyroid gland.

The thyroid gland

The thyroid gland is below the Adam’s apple in the front part of the neck. It is butterfly shaped, with 2 lobes — the right lobe and the left lobe — joined by a narrow structure called the isthmus (see picture below).

 

The thyroid gland has 2 main types of cells:

  • Follicular cells use iodine from the blood to make thyroid hormone, which helps control how the body uses energy. Having too much thyroid hormone (a condition called hyperthyroidism) can cause a rapid or abnormal heartbeat, trouble sleeping, nervousness, hunger, weight loss, and a feeling of being too warm. Having too little hormone (called hypothyroidism) causes a person to slow down, feel tired, and gain weight.
  • C cells (also called parafollicular cells) make calcitonin, a hormone that helps control how the body uses calcium.

Other, less common cells in the thyroid gland include immune system cells (lymphocytes) and supportive (stromal) cells.

Different cancers can start from each kind of cell. The type of cell where the cancer starts is important because it affects how serious the cancer is and what type of treatment is needed.

Many types of growths and tumors can start in the thyroid gland. Most are benign (non-cancerous) but some are malignant (cancerous), which means they can spread into nearby tissues and to other parts of the body. The information here covers only cancerous tumors of the thyroid.

Malignant (cancerous) thyroid tumors

There are several types of thyroid cancer.

Differentiated thyroid cancers

Most thyroid cancers are differentiated cancers. These cancers start in thyroid follicular cells. In these cancers, the cells look a lot like normal thyroid tissue when seen under a microscope.

Papillary thyroid cancer: About 8 of 10 thyroid cancers are papillary cancers. Most often they grow very slowly. Often they grow in only one lobe of the thyroid gland. Even though they grow slowly, they often spread to the lymph nodes in the neck. But most of the time, these cancers can be cured and are rarely fatal.

Follicular thyroid cancer: This is the next most common type of thyroid cancer. It is much less common than papillary thyroid cancer, making up about 1 out of 10 thyroid cancers. Follicular cancers usually stay in the thyroid gland. They usually don’t spread to lymph nodes, but some can spread to other parts of the body, such as the lungs or bones. The outlook for follicular cancer may not be quite as good as that of papillary cancer, but it is still very good in most cases.

Hürthle cell cancer is a kind of follicular cancer. It accounts for a very small number of thyroid cancers. The outlook may not be as good as that of typical follicular cancer because this type is harder to find and treat.

Other types of thyroid cancers

These cancers occur less often than differentiated thyroid cancers.

Medullary thyroid cancer (MTC): This accounts for about 4% of thyroid cancers. It starts in the C cells of the thyroid gland. In some cases MTC can run in families. Sometimes these cancers can spread to other parts of the body even before a lump is found in the thyroid. The outlook for these cancers is not quite as good as that for differentiated thyroid cancers.

Anaplastic thyroid cancer: This is a rare type of thyroid cancer, making up about 2% of all thyroid cancers. This cancer is also called undifferentiated because the cancer cells do not look very much like normal thyroid cells under the microscope. It is a fast-growing cancer that often spreads quickly into the neck and to other parts of the body and is very hard to treat.

There are several other fairly rare types of thyroid cancers. To learn more about them, see our detailed document, Thyroid Cancer.

Parathyroid cancer

Behind, but attached to, the thyroid gland are 4 tiny glands called the parathyroids. The parathyroid glands help control the body’s calcium levels. Cancers of the parathyroid glands are very rare — there are probably fewer than 100 cases each year in the United States.

Parathyroid cancers are often found because they raise the blood calcium level, causing a person to become tired, weak, and drowsy. High calcium also makes you urinate (pee) a lot. Larger parathyroid cancers may also be found as a lump (nodule) near the thyroid.

Parathyroid cancer is treated with surgery, but it is much harder to cure than thyroid cancer.

The rest of this document only covers thyroid cancer.

 

What are the risk factors for thyroid cancer?

While the exact cause of most thyroid cancers is not known, several risk factors have been linked to the disease. A risk factor is anything that affects a person’s chance of getting a disease such as cancer. Different cancers have different risk factors. Some risk factors, like smoking, can be changed. Others, like a person’s age or family history, can’t be changed.

But risk factors don’t tell us everything. Having a risk factor, or even several risk factors, does not mean that you will get the disease. And many people who get the disease may have few or no known risk factors. Even if a person with thyroid cancer has a risk factor, it is very hard to know what part that risk factor might have played in the cancer.

Below are some risk factors that make a person more likely to develop thyroid cancer.

Gender and age

Thyroid cancers (like almost all diseases of the thyroid) happen about 3 times more often in women than in men. The reason for this is not known.

Thyroid cancer can occur at any age. But women are most likely to get it in their 40s or 50s, while men are more likely to get it in their 60s or 70s

A diet low in iodine

Follicular thyroid cancers are more common in places where people’s diets are low in iodine. In the United States, most people get enough iodine in their diet because it is added to table salt and other foods.

Radiation

Exposure to radiation is a proven risk factor for thyroid cancer. Sources of such radiation include certain medical treatments and radiation fallout from power plant accidents or nuclear weapons.

Having had radiation treatments to the head or neck in childhood is a risk factor for thyroid cancer. Risk depends on the dose of radiation and the age of the child. Before the 1960s, children were sometimes treated with low doses of radiation for things we wouldn’t use radiation for now, like acne, ringworm, and other problems. Years later, the people who had these treatments were found to have a higher risk of thyroid cancer.

Imaging tests such as x-rays and CT scans also expose children to radiation, but at much lower doses. If there is an increased risk of thyroid cancer from these tests it is likely to be small, but to be safe, children should not have these tests unless they are clearly needed.

Being exposed to radiation as an adult carries much less risk of thyroid cancer.

Hereditary conditions and family history

Several inherited conditions have been linked to different types of thyroid cancer, as has family history. Still, most people who get thyroid cancer do not have an inherited condition or a family history of the disease.

Medullary thyroid cancer

Some cases of medullary thyroid cancer result from a person inheriting an abnormal gene from a parent. This is known as familial medullary thyroid cancer (FMTC). FMTC can occur alone, or it can be seen along with other tumors, as part of a syndrome called multiple endocrine neoplasia type 2 (MEN 2). These cancers often appear in childhood or early adulthood and can spread early.

Other thyroid cancers

People with certain inherited medical problems have a higher risk of more common forms of thyroid cancer. Higher rates of thyroid cancer are seen in people with rare genetic conditions such as:

  • Familial adenomatous polyposis (FAP)
  • Gardner syndrome
  • Cowden disease
  • Carney complex, type I

To learn more about these conditions, please see our document, Thyroid Cancer.

Papillary and follicular thyroid cancers also seem to run in some families without known genetic conditions. Having a parent, brother, sister, or child with thyroid cancer increases your risk of thyroid cancer.

If you think you might have an increased risk of thyroid cancer, talk to your doctor. Genetic counseling might be suggested if your background warrants it.

 

How is thyroid cancer found?

Many thyroid cancers can be found early. Most early thyroid cancers are found when patients see their doctors because of neck lumps or bumps they have noticed. If you have symptoms such as a lump or swelling in your neck, you should see your doctor right away.

Other cancers are found by the doctor during a routine checkup or when people have ultrasound tests of the neck for other health problems.

Blood tests or thyroid ultrasound can often find changes in the thyroid, but these tests are not used as screening tests for thyroid cancer unless there is a reason (such as family history) to suspect a person is at a higher risk for thyroid cancer.

People with a family history of medullary thyroid cancer (MTC) might have a very high risk for getting this cancer. Most doctors suggest genetic testing for these people when they are young to see if they carry the gene changes linked to MTC. For people who may be at risk but don’t get genetic testing, blood tests can help find MTC at an early stage, when it may still be cured. Thyroid ultrasounds may also be done in high-risk people.

Signs and symptoms of thyroid cancer

Thyroid cancer can cause any of these signs or symptoms:

  • A lump in the neck, sometimes growing quickly
  • Swelling in the neck
  • Pain in the front of the neck, sometimes going up to the ears
  • Hoarseness or other voice changes that do not go away
  • Trouble swallowing
  • Trouble breathing
  • A constant cough that is not due to a cold

If you have any of these signs or symptoms, talk to your doctor right away. Many of these symptoms can be caused by other things. Thyroid lumps (nodules) are common and are usually benign. Still, if you have any of these problems, see your doctor right away so the cause can be found and treated, if needed.

Medical history and physical exam

If you have any signs or symptoms that suggest you might have thyroid cancer, your doctor will want to get your complete medical history. You will be asked questions about your possible risk factors, symptoms, and any other health problems or concerns. If someone in your family has had thyroid cancer or certain kinds of tumors (called pheochromocytomas), tell your doctor, as you might be at high risk for this disease.

During the physical exam, your doctor will pay special attention to the size and firmness of your thyroid and any enlarged lymph nodes in your neck.

Biopsy

A final diagnosis of thyroid cancer is made with a biopsy, in which cells from the area of concern are removed and looked at under a microscope. But this might not be the first test done if you have a lump in your neck. The doctor might order other tests first, such as blood tests, an ultrasound exam, or a radioiodine scan to get a better sense of whether you might have thyroid cancer. These tests are described below.

If your doctor thinks a biopsy is needed, the simplest way to find out if a thyroid lump or nodule is cancer is by doing a fine needle aspiration (FNA) biopsy.

This type of biopsy can usually be done in your doctor’s office or clinic. Before the biopsy, medicine may be used to numb the skin over the nodule. Your doctor will then put in a thin, hollow needle into the lump to draw out cells and a few drops of fluid. The doctor usually repeats this 2 or 3 times to take samples from several places. The cells can then be looked at under a microscope to see if they look like cancer.

If a nodule is too small for the doctor to feel, sometimes FNA biopsies can be done using an ultrasound machine to help the doctor find the right place to put the needle.

Sometimes an FNA biopsy will need to be repeated because the samples didn’t contain enough cells. Most FNA biopsies will show that the thyroid nodule is benign. Only about 1 out of every 20 biopsies will clearly show cancer.

Sometimes the test results come back as “suspicious” or “of undetermined significance” if the FNA findings don’t show for sure whether the nodule is cancer or not. If this happens, the doctor may order tests on the sample to see if the cells have certain gene changes. Finding these changes makes thyroid cancer much more likely.

In some cases, another biopsy may be needed to get a better sample. This might include a biopsy using a larger needle or a surgical “open” biopsy to remove the nodule or a larger part of the thyroid gland. This kind of biopsy is done in the hospital while you are in a deep sleep.

Imaging tests

Imaging tests make pictures of the inside of your body. They may be done for a number of reasons:

  • To find suspicious areas that might be cancer
  • To learn how far cancer may have spread

To help find out if treatment has been workingUltrasound

Ultrasound uses sound waves to create pictures of parts of your body. For this test, a small wand is placed on the skin in front of your thyroid gland. It gives off sound waves and picks up the echoes as they bounce off the thyroid. The echoes are seen as a black and white image on a computer screen. No radiation is used in this test.

This test can help show if thyroid nodules are solid or filled with fluid. (Solid ones are more likely to be cancer.) It can also be used to help guide a biopsy needle into a nodule to take a sample. Ultrasound can also help show whether any nearby lymph nodes are enlarged because the thyroid cancer has spread.

Radioiodine scan

Radioiodine scans can be used to help find out if someone with a lump in the neck might have thyroid cancer. They are also often used in patients with differentiated thyroid cancer to help show if it has spread. (Medullary thyroid cancer cells do not take up iodine, so radioiodine scans are not used for this cancer.)

For this test, a small amount of radioactive iodine is swallowed as a pill or put into a vein. Over time, the iodine is absorbed by the thyroid cells. A special camera is used several hours later to see the radioactivity.

For a thyroid scan, the camera is placed in front of your neck to measure the amount of radiation in the gland. Abnormal areas of the thyroid that have less radioactivity than the surrounding tissue are called cold nodules, and areas that take up more radiation are called hot nodules. Hot nodules usually are not cancer, but cold nodules can be either benign or cancer. So this test by itself can’t diagnose thyroid cancer.

After surgery for thyroid cancer, whole-body radioiodine scans are useful in looking to see if cancer has spread throughout the body.

Radioactive iodine can also be used to treat differentiated thyroid cancer, but it is given in much higher doses. This type of treatment is described in the section, “Radioactive iodine treatment.”

Chest x-ray

If you have thyroid cancer, your chest may be x-rayed to see if cancer has spread to your lungs.

Computed tomography (CT) scan

The CT scan is an x-ray test that gives detailed pictures of your body. The CT scan can help show the place and size of thyroid cancers and whether they have spread to nearby areas. A CT scan can also be used to look for spread into distant organs like the lungs.

A CT scanner has been described as a large donut, with a narrow table in the middle opening. You will need to lie still on the table while the scan is being done. CT scans take longer than regular x-rays, and you might feel a bit confined by the ring while the pictures are being taken.

Instead of taking one picture, like a regular x-ray, a CT scanner takes many pictures as it rotates around you while you lie on a table. A computer then combines these pictures.

Before the test, you may be asked to drink a contrast solution or receive an IV (intravenous) line through which a different contrast dye is put in. This helps better outline structures in your body. You might feel some flushing (a feeling of warmth). Some people are allergic and get hives. Rarely, more serious problems like trouble breathing or low blood pressure can happen. Be sure to tell the doctor if you have any allergies or have ever had any problems from contrast dye used for x-rays.

In some cases, a CT scan can be used to guide a biopsy needle right into a suspected area of cancer spread.

Because the CT contrast dye contains iodine, (which can cause problems with radioiodine scans described above), many doctors prefer MRI scans instead of CT scans.

Magnetic resonance imaging (MRI) scan

Like CT scans, MRI scans can be used to look for cancer in the thyroid or cancer that has spread to other parts of the body. But ultrasound is usually the first choice for looking at the thyroid. MRI scans are helpful in looking at the brain and spinal cord.

MRI scans use radio waves and strong magnets instead of x-rays. A contrast material is often put into a vein before the scan to better show the details.

MRI scans take longer than CT scans — often up to an hour. And you might have to lie inside a narrow tube, which can upset people who don’t like enclosed spaces. Newer, more open MRI machines can sometimes be used instead. The machine also makes buzzing and clicking noises that you may find disturbing. Some centers provide earplugs to block this noise out.

PET (positron emission tomography) scan

For a PET scan, a kind of radioactive sugar is put into the blood. The amount used is very low. Because cancer cells in the body are growing quickly, they absorb more of the sugar than normal cells. After waiting about an hour, you lie on a table in the PET scanner for about 30 minutes while a special camera creates a picture of areas of radioactivity in the body.

This test can be very useful if your thyroid cancer is one that doesn’t take up radioactive iodine. In this case, the PET scan may be able to tell whether the cancer has spread.

Some newer machines are able to do both a PET and CT scan at the same time. This lets the doctor see areas that “light up” on the PET scan in more detail.

Blood tests

Blood tests alone can’t tell if a person has thyroid cancer. But they can help show if the thyroid is working as it should, which may help the doctor decide what other tests may be needed.

Medullary thyroid cancer tests

If medullary thyroid cancer (MTC) is suspected or if you have a family history of the disease, blood tests of calcitonin levels can help look for MTC. Calcitonin is a hormone that helps control how the body uses calcium. This test also is useful in seeing if the cancer has come back after treatment.

People with MTC often have high blood levels of a protein called carcinoembryonic antigen (CEA). Tests for CEA can sometimes help find this cancer.

Tests used with other types of thyroid cancer

Your blood may be tested for levels of thyroid hormones (T3 and T4), thyroid-stimulating hormone (TSH), and thyroglobulin to see if the thyroid is working normally.

These tests can’t tell if you have thyroid cancer, but they may be done during and after cancer treatment to check thyroid function or to help find out if the cancer may have returned.

Other blood tests

You may have other blood tests as well. If you are scheduled for surgery, tests will be done to check your blood cell counts, to look for bleeding problems, and to check your liver and kidney function.

Vocal cord exam

Thyroid tumors can sometimes affect the vocal cords. If you are going to have surgery to treat thyroid cancer, a vocal cord exam probably will be done ahead of time to see if the vocal cords are moving the way they should. For this exam, the doctor looks down the throat at the voice box with special mirrors or with a thin tube with a light and a lens on the end (a laryngoscope).

 

How is thyroid cancer treated?

This information represents the views of the doctors and nurses serving on the American Cancer Society’s Cancer Information Database Editorial Board. These views are based on their interpretation of studies published in medical journals, as well as their own professional experience.

The treatment information in this document is not official policy of the Society and is not intended as medical advice to replace the expertise and judgment of your cancer care team. It is intended to help you and your family make informed decisions, together with your doctor.

Your doctor may have reasons for suggesting a treatment plan different from these general treatment options. Don’t hesitate to ask him or her questions about your treatment options.

About treatment

Depending on the type and stage of your thyroid cancer, you might need more than one type of treatment. Doctors on your cancer treatment team may include:

  • A surgeon: a doctor who uses surgery to treat cancers or other problems
  • An endocrinologist: a doctor who treats diseases in glands that secrete hormones
  • A radiation oncologist: a doctor who uses radiation to treat cancer
  • A medical oncologist: a doctor who uses chemotherapy and other medicines to treat cancer

Many other people may be part of your team as well, including physician assistants, nurse practitioners, nurses, psychologists, and social workers.

After thyroid cancer is found, your doctors will discuss your treatment options with you. It is a good idea to take time to think about each of them. In choosing a treatment plan, things to take into account include the type and stage of the cancer and your overall health. The treatment options for thyroid cancer might include:

The best approach often uses 2 or more of these methods.

Most thyroid cancers can be cured, especially if they have not spread to distant parts of the body. If a cure is not likely, the goal of treatment may be to remove or destroy as much of the cancer as possible and to keep it from growing, spreading, or coming back for as long as possible. Sometimes treatment is aimed at relieving symptoms such as pain or problems with breathing and swallowing. This treatment is called palliative care.

The next few sections describe the types of treatment used for thyroid cancers.

 

Some questions to ask your doctor about thyroid cancer

As you cope with cancer and cancer treatment, you need to have honest, open talks with your doctor. You should feel free to ask any question, no matter how small it might seem. Here are some questions you might want to ask. Be sure to add your own questions as you think of them. Nurses, social workers, and other members of the treatment team may also be able to answer many of your questions.

  • What kind of thyroid cancer do I have?
  • Has my cancer spread beyond the thyroid gland?
  • What is the stage of my thyroid cancer, and what does this mean?
  • Are there other tests that need to be done before we decide on treatment?
  • Is this form of thyroid cancer hereditary? Should my family be tested?
  • Are there other doctors I need to see?
  • How much experience do you have treating this type of cancer?
  • How much surgery do I need? Should I get other treatments as well?
  • What other treatment choices do I have?
  • What should I do to be ready for treatment?
  • What are the risks and possible side effects of treatment?
  • Will I need to take thyroid hormone for the rest of my life?
  • How long will treatment last? What will it involve? Where will it be done?
  • When can I go back to my normal activities after treatment?
  • Will this treatment affect my ability to have children? Do I need to avoid pregnancy for a while?
  • What are the chances that my cancer will come back after treatment?
  • What would we do if the treatment doesn’t work or if the cancer recurs?
  • What type of follow-up will I need after treatment?

No doubt you will have other questions. Be sure to write them down so that you remember to ask them during each visit with your cancer care team. For example, you might want to ask about getting a second opinion or about clinical trials for your cancer.

 

Moving on after treatment for thyroid cancer

For many people with thyroid cancer, treatment may remove or destroy the cancer. Completing treatment can be both stressful and exciting. You may be relieved to finish treatment, but find it hard not to worry about cancer growing or coming back. (When cancer comes back after treatment, it is called recurrence.) This is a very common concern in people who have had cancer.

It may take a while before your fears lessen. But it may help to know that many cancer survivors have learned to live with this uncertainty and are leading full lives. Our document, Living With Uncertainty: The Fear of Cancer Recurrence gives more detailed information on this.

For some people, thyroid cancer may never go away completely. These people may get regular treatments with chemo, radiation, or other treatments to help keep the cancer in check. Learning to live with cancer as a more of a chronic disease can be hard and very stressful. It has its own type of uncertainty.

Follow-up care

If you have finished treatment, your doctors will still want to watch you closely. It is very important to go to all follow-up visits. During these visits, your doctors will ask about symptoms, do an exam, and might order blood tests or tests such as radioiodine scans or ultrasounds. Follow-up is needed to check for cancer coming back or spreading, as well as possible side effects of certain treatments. This is the time for you to ask your health care team any questions or concerns you have.

Most people do very well after treatment, but follow-up care can go on for a lifetime. This is very important since most thyroid cancers grow slowly and can come back even 10 to 20 years after the first treatment. Your health care team will explain what tests you need and how often they should be done.

Papillary or follicular cancer: If you have had papillary or follicular cancer and your thyroid gland has been removed or destroyed, your doctors might do at least one radioiodine scan after your treatment is complete. This is usually done about 6 to 12 months later. If the result is normal, you will most likely not need further scans unless you have symptoms or other abnormal test results.

Your blood will also be tested for signs the cancer might be coming back. If the results are abnormal, further testing will be done. This usually includes a radioiodine scan, and may include PET scans and other imaging tests.

For those with a low-risk, small papillary cancer that was treated by taking out only one lobe of the thyroid, a physical exam by your doctor, as well as a thyroid ultrasound and chest x-ray once in a while is typical.

Medullary thyroid cancer: If you had medullary thyroid cancer (MTC), your doctors will check the levels of calcitonin and carcinoembryonic antigen (CEA) in your blood. If these begin to rise, tests, such as an ultrasound of the neck or a CT or MRI scan, will be done to look for any cancer coming back.

Each type of treatment for thyroid cancer has side effects that may last for a few months. Some, like the need for thyroid hormone pills, may last your lifetime. You may be able to speed your recovery by being aware of the side effects before you start treatment. You might be able to take steps to reduce them and shorten the length of time they last. Be sure to tell your cancer care team about any symptoms or side effects that bother you so they can help you manage them.

Seeing a new doctor

At some point after your cancer is found and treated, you may find yourself seeing a new doctor who does not know about your cancer. You need to be able to give your new doctor the exact details of your cancer and treatment. Gathering these details soon after treatment might be easier than trying to get them at some point in the future. Make sure you have this information handy and always keep copies for yourself:

  • Copies of your pathology reports from any biopsies or surgeries
  • Copies of imaging tests (CT or MRI scans, etc.), which can usually be stored on a CD, DVD, etc.
  • If you had surgery, a copy of your operative report
  • If you stayed in the hospital, a copy of the discharge summary that doctors prepare when patients are sent home
  • If you had radiation treatment, a summary of the type and dose of radiation and when and where it was given
  • If you had chemo, a list of the drugs, drug doses, and when you took them

It is also important to keep health insurance. Tests and doctor visits cost a lot, and even though no one wants to think of their cancer coming back, this could happen.

 

What’s new in thyroid cancer research?

Research into thyroid cancer is being done right now in many hospitals, medical centers, and other places around the country. Each year, scientists find out more about what causes the disease, how to prevent it, and how to improve treatment.

Genetics

The discovery of the genetic causes of familial (inherited) medullary thyroid cancer now makes it possible to identify family members carrying the abnormal gene and to remove the thyroid in these people to prevent cancer from starting there.

Progress in understanding the abnormal genes that cause sporadic (not inherited) thyroid cancer should also lead to better treatments.

Treatment

Most thyroid cancers can be cured. But advanced cancers can be hard to treat, especially if they do not respond to radioactive iodine therapy. Doctors and researchers are looking for better and safer ways to treat thyroid cancer.

Surgery

Surgery is often an effective treatment for most thyroid cancers without causing major side effects.

Some people who have thyroid surgery are bothered by the scar it leaves on the neck. Newer approaches to surgery may help with this. For example, doctors are now looking at doing surgery through smaller cuts in the neck, or even cuts under the arm.

Radioactive iodine (RAI) treatment

Doctors are looking for better ways to see which patients are likely to have their cancers come back after surgery. These patients may be helped by getting RAI treatment after surgery.

Researchers are also looking for ways to make RAI effective against more thyroid cancers. For example, doctors are studying whether some newer drugs can be used to make thyroid cancer cells more likely to take up radioactive iodine.

Chemo

Some studies are testing the value of chemo drugs like paclitaxel (Taxol) and other drugs, as well as using chemo and radiation together in treating anaplastic thyroid cancer.

Targeted drugs

Most thyroid cancers do not respond well to chemo. But unlike standard chemo drugs, targeted drugs attack certain targets on cancer cells. Targeted drugs might work in some cases when standard chemo drugs do not, and they often have different (and less severe) side effects.

Tyrosine kinase inhibitors: A class of targeted drugs known as tyrosine kinase inhibitors (TKIs) may help treat thyroid cancer cells with changes in certain genes. Many of these drugs also keep new blood vessels from forming (see below).

Many papillary thyroid cancers have changes in the BRAF gene, which helps them grow. Drugs that target cells with BRAF gene changes are now being studied in thyroid cancers with this gene change.

Vandetanib (Caprelsa) and cabozantinib (Cometriq) are targeted drugs that are helpful in treating medullary thyroid cancer (MTC).

Some other TKIs are already approved to treat other types of cancer, and may be useful against MTC and differentiated thyroid cancers if other treatments are no longer working.

Anti-angiogenesis drugs: As tumors grow, they need a larger blood supply to get enough nutrients. They get it by causing new blood vessels to form (a process called angiogenesis). Anti-angiogenesis drugs work by blocking these new blood vessels.

Some of the TKIs have anti-angiogenic properties. Other anti-angiogenesis drugs, such as bevacizumab (Avastin), are also being studied.

 

By American Cancer Society