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Thyroid Cancer

Condition Basics

What is thyroid cancer?

Thyroid cancer is the growth of abnormal cells in your thyroid gland. These cells often form small tumours called nodules. But most thyroid nodules aren't cancer and don't cause harm.

There are several different types of thyroid cancer. The treatment for thyroid cancer is often successful with the right treatment plan.

What causes it?

Experts don't know what causes thyroid cancer. Like other cancers, changes in the DNA of your cells seem to play a role. These DNA changes may include changes that are inherited as well as those that happen as you get older.

What are the symptoms?

Many people don't have any symptoms when they are diagnosed with thyroid cancer. This cancer is often found when an imaging test is done for another reason. The most common symptom is a lump or swelling in your neck. Other symptoms may include pain or trouble swallowing. Or your voice may be hoarse.

How is it diagnosed?

If you have a lump in your neck that could be thyroid cancer, you'll likely have a fine-needle biopsy. This test may be all that is needed to diagnose thyroid cancer. In some cases, a molecular test or surgery will also be done to find out if a lump (nodule) is thyroid cancer.

How is thyroid cancer treated?

Treatment for thyroid cancer often includes surgery, radioactive iodine, and thyroid hormone therapy. It may include radiation therapy, chemotherapy, or targeted therapy. Very low-risk thyroid cancer may not need treatment right away. With regular checkups and tests, your doctor can closely watch the cancer for any signs of growth (active surveillance).

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Cause

Experts don't know what causes thyroid cancer. But like other cancers, changes in the DNA of your cells seem to play a role. These DNA changes may include changes that are inherited as well as those that happen as you get older.

People who have been exposed to a lot of radiation have a greater chance of getting thyroid cancer.

A dental X-ray now and then will not increase your chance of getting thyroid cancer. But past radiation treatment of your head, neck, or chest (especially during childhood) can put you at risk of getting thyroid cancer.

What Increases Your Risk

A risk factor for thyroid cancer is something that increases your chance of getting this cancer. Having one or more of these risk factors can make it more likely that you will get thyroid cancer. But it doesn't mean that you will definitely get it. And many people who get thyroid cancer don't have any of these risk factors.

Risk factors include:

  • Being female.
  • Exposure to high levels of radiation, such as after a nuclear power incident.
  • A history of radiation treatments to the head, neck, or chest during childhood.
  • A personal or family history of thyroid disease or thyroid cancer.
  • Inheriting gene changes that can cause thyroid cancer or other inherited conditions, like familial polyposis.

Lowering Your Risk

Most thyroid cancer cannot be prevented.

One rare type of thyroid cancer, called medullary thyroid cancer (MTC), runs in families. A genetic test can tell you if you have a greater chance of getting MTC. If this test shows that you have an increased risk, you can have your thyroid gland removed to reduce your risk for thyroid cancer later in life.

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Symptoms

Many people don't have any symptoms when they are diagnosed with thyroid cancer. This cancer is often found when an imaging test, like a CT scan, is done for another reason.

When thyroid cancer grows, it may cause these symptoms:

  • You may get a lump or swelling in your neck. This is the most common symptom.
  • You may have pain in your neck and sometimes in your ears.
  • You may have trouble swallowing.
  • You may have trouble breathing or have constant wheezing.
  • Your voice may be hoarse.
  • You may have a frequent cough that is not related to a cold.

What Happens

Thyroid cancer is a disease that occurs when abnormal cells begin to grow in the thyroid gland. You may notice a lump in your neck and then go to your doctor. Or your doctor may notice a lump during a routine physical examination or on an imaging test that you are having for another health problem.

Almost all thyroid cancers are treated with surgery. After surgery, you may need to take thyroid hormone medicine for the rest of your life. Some people may also need to have radioactive iodine therapy. In cases where surgery isn't possible or radioactive iodine therapy doesn't work, other treatments are available.

In some cases, thyroid cancer can return after treatment. It can show up in the neck area or in another part of the body, such as the lungs. Follow-up care and tests can help catch thyroid cancer early if it returns.

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When to Call a Doctor

Call your doctor if you have any of the following symptoms:

  • A lump or swelling in your neck. This is the most common symptom of thyroid cancer.
  • Pain in your neck and sometimes in your ears that doesn't go away and is not caused by a cold or allergies
  • Hoarseness that is not related to a cold
  • Difficulty swallowing
  • Difficulty breathing or constant wheezing
  • A cough that continues and is not related to a cold
  • Bone pain

Examinations and Tests

To diagnose thyroid cancer, your doctor will ask about your medical history and do a physical examination. You may have tests, including:

If tests show that cancer is possible, you may have:

  • A fine needle biopsy. This removes a small sample of tissue to check for cancer cells.
  • Molecular tests. These tests look at cells from your biopsy.
  • Surgery. Sometimes the results of a biopsy or other tests aren't enough, and surgery is needed.

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Treatment Overview

Treatment for thyroid cancer is based on the type and stage of the cancer and other things, like your overall health. Treatment may include:

Active surveillance.
Very low-risk thyroid cancer may not need treatment right away. With regular checkups and tests, your doctor can closely watch the cancer for any signs of growth (active surveillance).
Surgery.

You'll probably have surgery to remove part or all of your thyroid gland. The doctor may also remove some lymph nodes to check them for cancer.

Radioactive iodine.

You may get radioactive iodine to destroy any thyroid tissue that remains after surgery.

Thyroid hormone therapy.

After surgery, you'll probably take a daily pill to replace hormones normally made by the thyroid gland. This can also help keep thyroid cancer from coming back.

Sometimes treatment includes radiation therapy, chemotherapy, and targeted therapy.

Your doctor will talk with you about your options before making a treatment plan.

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Supportive Care

Hospice palliative care is a type of care for people who have a serious illness. It's different from care to cure your illness, called curative treatment. Hospice palliative care provides an extra layer of support that can improve your quality of life—not just in your body, but also in your mind and spirit. Sometimes hospice palliative care is combined with curative treatment.

The kind of care you get depends on what you need. Your goals guide your care. You can get both hospice palliative care and care to treat your illness. You don't have to choose one or the other.

Hospice palliative care can help you manage symptoms, pain, or side effects from treatment. It may help you and those close to you better understand your illness, talk more openly about your feelings, or decide what treatment you want or don't want. It can also help you communicate better with your doctors, nurses, family, and friends.

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Self-Care

There are things you can do to help manage the effects of cancer and the side effects of treatment.

  • Take your medicines exactly as prescribed. Call your doctor if you think you are having a problem with your medicine.
  • Eat healthy food. If you don't feel like eating, try to eat food that has protein and extra calories to keep up your strength and prevent weight loss. Drink liquid meal replacements for extra calories and protein. Try to eat your main meal early in the day.
  • Get some physical activity every day, but don't get too tired. Keep doing the things you enjoy as your energy allows.
  • Take steps to manage your stress, such as learning relaxation techniques. To also help reduce stress, get enough sleep, eat a healthy diet, and take time to do things you enjoy.
  • Think about joining a support group. Or discuss your concerns with your doctor or a counsellor.
  • If you are vomiting or have diarrhea:
    • Drink plenty of fluids to prevent dehydration. Choose water and other clear liquids. If you have kidney, heart, or liver disease and have to limit fluids, talk with your doctor before you increase the amount of fluids you drink.
    • When you are able to eat, try clear soups, mild foods, and liquids until all symptoms are gone for 12 to 48 hours. Other good choices include dry toast, crackers, cooked cereal, and gelatin dessert, such as Jell-O.

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Complementary Treatments

Some people use complementary therapies along with medical treatment. They may help relieve the symptoms and stress of cancer or the side effects of cancer treatment. Therapies that may be helpful include:

  • Acupuncture to relieve pain and other symptoms.
  • Meditation or yoga to relieve stress.
  • Massage and biofeedback to reduce pain and tension.
  • Breathing exercises to help you relax.

Talk with your doctor about any of these options you would like to try. And let your doctor know if you are already using any complementary therapies. They are not meant to take the place of standard medical treatment. But they may help you feel better and cope better with treatment.

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Getting Support

Relationships take on new importance when you're faced with cancer. Your family and friends can help support you. You may also want to look beyond those who are close to you.

  • Reach out to your family and friends.

    Remember that the people around you want to support you, and asking for help isn't a sign of weakness.

  • Tell them how they can help.

    Your friends and family want to help, but some of them may not know what to do. It may help to make a list. For example, you might ask them to:

    • Run errands or pick up kids.
    • Deliver meals or groceries to your home.
    • Drive you to appointments.
    • Go to doctor visits with you and take notes.
  • Look for help from other sources.

    Places to turn for support include:

    Counselling.
    Counselling can help you cope with cancer and the effect cancer is having on your life. Different types of counselling include family therapy, couples therapy, group counselling, and individual counselling.
    Your health care team.
    Your team should be supportive. Be open and honest about your fears and concerns. Your doctor can help you get the right medical treatments, including counselling.
    Spiritual or religious groups.
    These groups can provide comfort and may be able to help you find counselling or other social support services.
    Social groups.
    Social groups can help you meet new people and get involved in activities you enjoy. Focus on activities that bring you comfort, such as spending time outdoors or being with children.
    A cancer support group.
    Cancer support groups offer support and practical advice. You can hear others talk about:
    • What it's like to live with cancer.
    • Practical ways to manage your cancer treatment and its side effects.
    • Ways to cope with your illness.

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Credits

Current as of: March 1, 2023

Author: Healthwise Staff
Medical Review:
E. Gregory Thompson MD - Internal Medicine
Kathleen Romito MD - Family Medicine
Adam Husney MD - Family Medicine
Matthew I. Kim MD - Endocrinology