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Targeted therapy for thyroid cancer
Targeted therapy is sometimes used to treat thyroid cancer. It uses drugs to target specific molecules (such as proteins) on or inside cancer cells. These molecules help send signals that tell cells to grow or divide. By targeting these molecules, the drugs stop the growth and spread of cancer cells while limiting harm to normal cells. Targeted therapy may also be called molecular targeted therapy.
Targeted therapy is used for some types of locally advanced or metastatic thyroid cancer or for cancer that doesn’t respond to other treatments. It is often used for differentiated thyroid cancer (papillary or follicular carcinoma) when radioactive iodine therapy hasn’t worked or has stopped working. Targeted therapy is also used for recurrent medullary carcinoma. You may have targeted therapy to:
- slow or stop the growth and spread of cancer cells
- relieve or control symptoms of advanced thyroid cancer (called palliative therapy)
Your healthcare team will consider your personal needs to plan the drugs, doses and schedules of targeted therapy. You may also receive other treatments.
Targeted therapy drugs used for thyroid cancer
The most common targeted therapy drugs used are:
- sorafenib (Nexavar) for differentiated thyroid cancer
- lenvatinib (Lenvima) for differentiated thyroid cancer
- vandetanib (Caprelsa) for medullary carcinoma
Sorafenib, lenvatinib and vandetanib are kinase inhibitors. Kinases are proteins on the surface of cells that send signals to help cells grow and form new blood vessels. Sorafenib, lenvatinib and vandetanib block the action of different kinases, which helps slow or stop cancer cells from growing and spreading.
Sorafenib, lenvatinib and vandetanib are given daily as a pill by mouth (orally). They are usually given until the disease progresses again or the side effects outweigh the benefits of having the treatment.
Side effects can happen with any type of treatment for thyroid cancer, but everyone’s experience is different. Some people have many side effects. Other people have few or none at all.
Targeted therapy doesn’t usually damage healthy cells, so it tends to cause fewer and less severe side effects than chemotherapy and radiation therapy. Chemotherapy and radiation therapy can damage healthy cells along with cancer cells.
If side effects develop with targeted therapy, they can happen any time during, immediately after or a few days or weeks after targeted therapy. Sometimes late side effects develop months or years after targeted therapy. Most side effects usually go away once the drug is stopped. Less often, side effects may last a long time or become permanent.
Side effects of targeted therapy will depend mainly on the type of drug, the dose, how long it’s given and your overall health. Some common side effects of targeted therapy for thyroid cancer are:
- muscle cramps or weakness, irregular heartbeat and confusion caused by abnormal electrolyte levels
- a rash or other skin problems
- feeling cold, feeling tired and having dry skin when there is not enough thyroid hormone (called hypothyroidism)
- jaundice caused by abnormal liver function
- loss of appetite, weight loss or both
- high blood pressure (called hypertension)
- heart problems
Tell your healthcare team if you have these side effects or others you think might be from targeted therapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.
Information about specific cancer drugs
Details on specific drugs change quite regularly. Find out more about sources of drug information and where to get details on specific drugs.
Questions to ask about targeted therapy
A substance in the blood and other body fluids that carries an electric charge. Electrolytes are responsible for the movement of nutrients and wastes into and out of cells to keep body fluids balanced and to allow muscles to function properly.
Examples of electrolytes include calcium, chloride, potassium and sodium.