Thyroid Cancer

What is thyroid cancer?

If cells in the thyroid grow out of control, they form lumps called nodules or tumors. The thyroid is a small gland in the front of the neck near the windpipe. It is shaped like a butterfly and has 2 halves (lobes).

A healthy thyroid makes hormones that affect your child’s growth and development. They control how the body breaks down food and uses or stores the energy (metabolism).

Tumors can be cancerous (malignant) or noncancerous (benign). Thyroid cancer is rare in children and teens. Most kids who get it are cured.

Papillary carcinoma is the most common type of thyroid cancer in children.

Children can also get other types of thyroid cancer, including: 

  • Follicular carcinoma of the thyroid
  • Medullary carcinoma of the thyroid (MCT). Children with MCT often have an inherited genetic condition called multiple endocrine neoplasia type 2 (MEN 2).
  • What causes thyroid cancer is not known, but these may raise a child’s risk: 

    • Radiation exposure, including past medical treatment with radiation. Low levels of radiation, such as X-rays of the teeth, are not a risk factor.
    • Graves disease
    • Hashimoto disease
    • Family history of thyroid cancer (familial thyroid cancer)
    • Multiple endocrine neoplasia (MEN) syndromes
    • PTEN syndrome (Cowden syndrome)

Thyroid Cancer at Seattle Children’s

At Seattle Children’s, we have excellent results caring for children and teens with thyroid cancer. We treat more pediatric cancer than any other center in the region.

Your child will get care from doctors who are experts in childhood cancer (pediatric oncologists) and in disorders affecting the head and neck (otolaryngologists). 

  • If your child has been diagnosed with cancer, contact our Cancer and Blood Disorders Center at 206-987-2106.
  • If your child needs their thyroid checked or has a referral for a fine-needle aspiration biopsy of the thyroid, contact Otolaryngology at 206-987-2105. Before scheduling a fine-needle biopsy, your child will need a blood test to measure thyroid-stimulating hormone (TSH). Your primary care doctor can order this test.
  • Seattle Children’s has the only multidisciplinary program in the Pacific Northwest that specializes in children and teens with thyroid conditions. The Thyroid Program brings together experts from oncologyotolaryngologypediatric surgeryendocrinology and other fields to diagnose all types of thyroid conditions and provide treatment tailored to your child.

    We have treated many children with thyroid cancer with excellent results. Our head and neck surgeons do many thyroid surgeries each year. We are considered a high-volume surgical center.

    For more than a decade, our Cancer Center has been consistently ranked among the top pediatric oncology programs in the country by U.S. News & World Report. For 2019-20, it has the highest ranking in the Northwest.

    Through our partnership in the Seattle Cancer Care Alliance (SCCA), your child will benefit from the work of physician-scientists at Fred Hutch and UW Medicine, as well as at Seattle Children’s. The National Cancer Institute has designated our partnership a comprehensive cancer center.

  • When we need to get a sample of tissue from your child’s thyroid, Seattle Children’s surgeons perform fine-needle aspiration biopsies. This means we take a sample of cells using a very thin needle guided by ultrasound. It is less invasive than cutting into the skin.

    For most children, we can do a physical exam and a fine-needle aspiration biopsy in the same clinic visit and avoid the need for medicine that puts your child to sleep (general anesthesia).

  • We offer the most advanced treatment options for thyroid tumors, including surgery and targeted radiation therapy.

    Seattle Children’s is well known for developing promising new cancer treatments and leading research studies with the goal of improving cure rates. As leaders in research groups like the Children’s Oncology Group (COG), we can offer our patients the very latest options being studied in clinical trials.

    Our clinical trials include a new targeted therapy for children whose thyroid cancer cells have a specific set of genetic changes. See Different Cancers, Same Drug: New Trial Targets Common Genetic Pathway in Tumors.

  • Children don’t react to illness, injury, pain and medicine in the same way as adults. They need – and deserve – care designed just for them. Our doctors base their treatment plans on years of experience and the newest research on what works best – and most safely – for children. Our experts focus on how treatments today affect growing bodies in the future.

    Our team cares for your whole child. We don’t just treat their disease. As needed, your child will receive care from specialists in nutrition, pain management, pharmacy, physical therapy and emotional health. Read more about the supportive care we offer.

  • Learning that your child has a thyroid tumor can be scary. We help take positive steps right away by offering appointments in 1 to 3 days to children suspected to have cancer.

    During visits, we take time to explain your child’s condition. We help you fully understand your treatment options and make the choices that are right for your family.

    Our doctors, nurses, child life specialists and social workers help your child and your family through the challenges of their illness. We connect you to community resources and support groups.

    At Seattle Children’s, we work with many children and families from around the Northwest and beyond. Whether you live nearby or far away, we can help with financial counseling, schooling, housing, transportation, interpreter services and spiritual care. Read about our services for patients and families.

Symptoms of Thyroid Cancer

Thyroid cancer may not cause symptoms in your child. But some children have: 

  • A lump in the neck that you can feel
  • Voice changes because the tumor is pressing on the voice box or nerves to the vocal cords
  • Trouble breathing or swallowing 

Check with a doctor if your child has these symptoms, which may be caused by thyroid cancer or by another condition.

If your child has no symptoms, you may find out about a thyroid problem because the doctor feels something that is not normal in your child’s neck during a regular check-up.

Diagnosing Thyroid Cancer

To diagnose thyroid cancer, the doctor will: 

  • Ask about your child’s health background.
  • Do an exam, which will include feeling your child’s thyroid to tell whether it is a normal size and shape and whether it has lumps.
  • Do blood tests to check the levels of thyroid hormones and antibodies that can affect how the thyroid works. 

To get more information about your child’s condition, the doctor may also do 1 or more of these tests:

  • Imaging studies show doctors pictures of the inside of your child’s body. They help doctors see the size and texture of your child’s thyroid and check for nodules or other signs of disease. These studies may include: 

    • Ultrasound of your child’s neck
    • CT (computed tomography) scan
    • MRI (magnetic resonance imaging) scan
    • Radioactive iodine scan. This test works well for thyroid conditions because only thyroid cells take up iodine. Your child swallows a small amount of radioactive iodine (I-123). It travels through their blood and collects in the thyroid gland. A special camera linked to a computer makes pictures that show areas in the thyroid that do not absorb iodine in the normal way.
  • The purpose of a biopsy is to tell whether a lump is cancer (malignant) or not cancer (benign).

    At Seattle Children’s, our surgeons often use a biopsy method called fine-needle aspiration. This avoids giving your child medicine to make them sleep (general anesthesia). You and your child are in control – if your child feels too nervous about being awake during the biopsy, we schedule a biopsy under general anesthesia.

    For most children, we can do a physical exam and a fine-needle aspiration biopsy in the same clinic visit.

    To do the procedure, the doctor will: 

    • Numb the front of your child’s neck using a needle-free device (called a J-tip). It pushes medicine into your child’s skin with a strong puff of air.
    • Use a very thin needle (thinner than for a blood draw) to take a sample of cells. Ultrasound guides the needle to the right place. 

    The biopsy visit takes about 1 hour. We have results for you in about 1 week.

    Fine-Needle Aspiration Biopsy at Seattle Children’s (Video. 3:07)

    Dr. Scott Manning explains this painless way to check a thyroid lump.

Treating Thyroid Cancer

Many of our patients return to their normal lives after treatment and never have cancer again. The doctors at Seattle Children’s Thyroid Program and Cancer and Blood Disorders Center tailor treatment to your child’s age and the needs of their growing body.

Your child’s health care team will suggest a treatment plan based on: 

  • The tumor size
  • Whether it has spread to the lymph nodes or other parts of the body
  • Whether your child has had radiation therapy or other exposure to radiation
  • If blood tests show a tumor marker (called thyroglobulin)
  • Your child’s age and overall health
  • Your family’s preferences 

The most common treatment for thyroid cancer is surgery. Some children need targeted radiation therapy. Very few kids with thyroid cancer get chemotherapy. Seattle Children’s offers these treatment options:

  • If your child has lumps in their thyroid that might be cancer or are cancer, they will have surgery. 

    • If the area of concern is only in 1 half, or lobe, of the thyroid, surgeons may remove only that half. This surgery is called lobectomy.
    • If there are concerns about both lobes, they will remove the whole thyroid. This is called total thyroidectomy. 

    If there is cancer in the thyroid, doctors will also check whether the cancer has spread to nearby lymph nodes or other parts of the body. These may need to be removed, too.

    Surgery is done at our hospital’s main campus in Seattle.

    Learn more about Thyroidectomy surgery to treat tumors at Seattle Children’s.

  • A few months after surgery to remove their thyroid tumor, we will check if any cancer cells remain in your child’s body. We often use a radioactive iodine scan (RAI).

    If the test finds thyroid cancer cells, doctors will likely recommend targeted radiation with I-131. More than half of the patients we treat for thyroid cancer get targeted radiation. 

    • Your child swallows a small amount of radioactive iodine.
    • The amount of radiation depends on how many thyroid tumor cells were found.
    • The radiation only affects the thyroid and thyroid cancer cells because only thyroid tissue takes up iodine.
  • If your child has surgery to remove the whole thyroid, they will need to take thyroid hormone replacement pills for life so their body gets this important hormone. If only half of the thyroid is removed, the other half will make enough thyroid hormone to meet their needs.

  • If multiple endocrine neoplasia type 2 (MEN 2) runs in your family, your doctor may suggest genetic testing and genetic counseling. This can help tell whether your child has MEN 2 and can give you information about your options.

    Children with MEN 2 nearly always get thyroid cancer, so families may choose to have the child’s thyroid removed early on – usually before age 5 – to prevent cancer from starting.

  • Many children, adolescents and young adults choose to take part in research studies while receiving their standard medical treatment. These studies are called clinical or therapeutic trials.

    In some cases, we can test a child’s cancer cells for changes in genes and take a precision medicine approach. Children whose cancer cells have a specific set of genetic changes may be helped by a clinical trial studying a new targeted therapy drug. 

    • This drug (larotrectinib) targets a class of proteins known as TRK that can cause certain types of cancers.
    • It works by targeting activated TRK and the tumor itself.
    • This is different from treatments like chemotherapy and radiation, which have more widespread effects on the body. 

    See Different Cancers, Same Drug: New Trial Targets Common Genetic Pathway in Tumors

    Learn more about cancer clinical trials at Seattle Children’s 

Follow-Up Care

Follow-up care is important after treatment ends – no matter what type of treatment your child had. The follow-up routine will depend on your child’s tumor and their treatments.

If they are taking thyroid hormone replacement, your child will need regular blood tests to make sure they get the right amount. Most of our patients who had cancerous tumors visit Seattle Children’s for follow-up care for 5 years. If you live far from Seattle, your child may get some follow-up care from a cancer doctor in your own community.

Our Cancer Survivor Program provides long-term follow-up care to help young people stay healthy after being treated for cancer in childhood.

During follow-up visits at Seattle Children’s, your child’s team will: 

  • Look for any signs that cancer is returning
  • Check for effects that may happen months or years after treatment
  • Tell you and your child about any risk for other cancers and signs to watch for

Contact Us

To make an appointment, you can call us directly or get a referral from your child’s primary care provider. We encourage you to coordinate with your pediatrician or family doctor when coming to Seattle Children’s.

  • If your child has been diagnosed with cancer, contact our Cancer and Blood Disorders Center at 206-987-2106 for an appointment, a second opinion or more information.
  • If your child needs their thyroid checked or has a referral for a fine-needle aspiration biopsy of the thyroid, contact Otolaryngology at 206-987-2105. Before scheduling a fine-needle biopsy, your child will need a blood test to measure thyroid-stimulating hormone (TSH). Your primary care doctor can order this test.

Providers, see how to refer a patient to our: