Chemotherapy for Thyroid Cancer

Chemotherapy (chemo) uses anti-cancer drugs that are injected into a vein or muscle, or are taken by mouth. Chemotherapy is systemic therapy, which means that the drug enters the bloodstream and travels throughout the body to reach and destroy cancer cells.

Chemotherapy is seldom helpful for most types of thyroid cancer, but fortunately it is not needed in most cases. It is combined with external beam radiation therapy for anaplastic thyroid cancer and is sometimes used for other advanced cancers that no longer respond to other treatments.

Possible side effects

Chemo drugs attack cells that are dividing quickly, which is why they work against cancer cells. But other cells in the body, such as those in the bone marrow, the lining of the mouth and intestines, and the hair follicles, also divide quickly. These cells are also likely to be affected by chemotherapy, which can lead to side effects.

The side effects of chemotherapy depend on the type and dose of drugs given and the length of time they are taken. Common side effects of chemo include:

• Hair loss
• Mouth sores
• Loss of appetite
• Nausea and vomiting
• Diarrhea
• Increased chance of infections (from too few white blood cells)
• Easy bruising or bleeding (from too few low blood platelets)
• Fatigue (from too few low red blood cells)

These side effects are usually short-term and go away after treatment is finished. There are often ways to lessen these side effects. For example, drugs can be given to help prevent or reduce nausea and vomiting.

Some chemotherapy drugs may have other specific side effects that require monitoring. For example, doxorubicin (one of the most common chemo drugs used in thyroid cancer) can affect heart function. Therefore, a patient taking doxorubicin will get regular heart function tests like echocardiograms.

For more information see the Chemotherapy section on our website.