Second cancer: Thyroid cancer

What is thyroid cancer as a second form of cancer?

This page belongs to Second form of cancer. We recommend reading that information first.

The thyroid gland is located just above the hollow of your neck and produces hormones. Thyroid hormones regulate all cells and organs in the body. For children, these hormones are important for growth and brain development. Sometimes thyroid cells behave abnormally and form a tumor. Most thyroid tumors are benign, but when thyroid cells begin to divide uncontrollably, a malignant tumor develops. A thyroid tumor is almost always curable.

The chance of developing thyroid cancer after childhood cancer is very small.

Do I have an increased risk of a thyroid tumor?

Everyone, including people who have not had cancer, can develop thyroid cancer. However, some cancer treatments can increase the risk.

The following treatments can increase the risk of a thyroid tumor:

• Radiation to the neck or to an area where the thyroid gland is located

• Treatment with radioactive iodine

You can see in your treatment summary whether you have received one of these treatments. If you do not have a summary, you can contact the LATER clinic or the hospital where you were treated. Thyroid cancer does not always have to be caused by treatment. There may also be other causes. If cancer occurs more frequently in your family at a young age, this can increase the risk of thyroid cancer.

What are the symptoms and signs of a thyroid tumor?

Certain symptoms and signs may indicate thyroid cancer. Even if you do not have these symptoms and signs at the moment, it is important to recognize them in case you ever develop them.

The following symptoms and signs may indicate a thyroid tumor:

• A lump or swelling at the front of the neck that:

  • feels firm

  • usually does not hurt

  • grows slowly larger

Other, rarer symptoms and signs are:

• Difficulty swallowing

• Swollen glands in the neck

• Changed voice or unexplained hoarseness

• Difficulty breathing

Often these symptoms have a different cause. However, rapid diagnosis and treatment of thyroid cancer are very important. If you recognize any of these symptoms or signs, contact your general practitioner. Most thyroid tumors are benign.

I have an increased risk of a thyroid tumor. What tests are necessary and when?

During a visit to the LATER clinic, the LATER physician can perform a physical examination of your neck.

If you have an increased risk of thyroid cancer, you and your LATER physician will decide together how the check-ups will be:

• An ultrasound of the thyroid every 3–5 years, starting 5 years after the end of radiation

• Or a physical examination of the neck every 1–2 years, starting 5 years after the end of radiation

What happens if I might have a thyroid tumor?

If you might have thyroid cancer, your general practitioner or LATER physician will refer you to an oncology team. This team may consist of:

• Medical oncologist

• Radiation oncologist

• Endocrinologist

• Surgeon

The oncology team will conduct further tests and discuss treatment options with you.

What else can I do?

Living with an increased risk of thyroid cancer can be difficult. Talking with friends and family can help. Contact with people in a similar situation can also be helpful, for example through a patient association such as VOX, part of the Dutch Childhood Cancer Association.

Take good care of yourself. Although it is not certain whether it reduces the risk of a thyroid tumor, a healthy lifestyle is important. Also take care of your mental wellbeing. Small changes can already have a positive impact on your physical and mental health.

It is important that you know you have an increased risk of a thyroid tumor and that you recognize the symptoms and signs. If you have questions or if you are concerned after reading this information, contact your general practitioner or LATER physician.

Where can I find more information?

This LATER website also contains information about:

• Healthy lifestyle

• Mental health

• Thyroid problems

• Second form of cancer

In the PanCare Plain Language Summaries you will find links to reliable information in English. You can search for information about thyroid tumors online, but keep in mind that it is not always up-to-date or accurate.

Disclaimer

This information is based on the plain language summary of the guideline created by the PanCare Plain Information Group and has been adapted to the Dutch LATER guideline where necessary. If you experience symptoms and signs, do not rely solely on this information, but consult your general practitioner, LATER physician, or specialist.

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