Unless you have thyroid lymphoma, you will probably have surgery to treat your cancer. Depending on how much of your thyroid is removed, you may need to take thyroid hormone pills to replace the hormone that your thyroid would normally make. You may also have radioactive iodine treatment. If you have thyroid lymphoma, you will most likely have traditional chemotherapy and/or radiation therapy.
Lymph Node Ultrasound and Central Neck Dissection
Before you have thyroid cancer surgery, you will have a thyroid ultrasound to determine if the lymph nodes in your neck look suspicious. This test uses sound waves to create a picture of the structures in your neck. If your tumor has spread or is likely to spread, your surgeon will remove any suspicious lymph nodes during your thyroid surgery.
The typical therapy for thyroid cancer (except for those with thyroid lymphoma) is to remove either all of the thyroid (total thyroidectomy) or half of the thyroid (thyroid lobectomy). Which operation you have will depend on how large your cancer is, whether it has spread, and your personal treatment goals. For patients with smaller, less aggressive cancers, thyroid lobectomy is often a good option.
Post-Surgery Blood Tests
Thyroglobulin is a protein made by thyroid cells. After removing your entire thyroid, the thyroglobulin level in your blood should be low. Your team will follow the thyroglobulin levels as a tumor marker to help monitor for cancer that comes back (recurrence). If you have had half of your thyroid removed, interpreting the thyroglobulin levels is more complex and requires an expert thyroidologist to interpret the levels.
Thyroid Hormone Replacement
Depending on how much of your thyroid is removed, you may have to take daily thyroid hormone replacement pills after thyroid surgery to give your body the hormones it needs to regulate your metabolism.
Normally, your pituitary gland signals your thyroid to make hormones by sending thyroid stimulating hormone, or TSH, into your blood. After your thyroid is removed, your thyroid hormone levels drop. Then your pituitary gland sends out more TSH to bring those levels back up.
Having too much TSH in your body can stimulate remaining cancer cells to grow and spread. Thyroid hormone replacement pills tell your pituitary gland that you have the right amount of thyroid hormone in your body and don’t need more TSH. For this reason, we sometimes will prescribe a slightly higher dose of thyroid hormone to suppress (i.e., block) the growth of thyroid tissue.
Medullary and anaplastic thyroid cancer do not originate in cells affected by TSH, so higher doses of thyroid hormone replacement doesn’t prevent them from coming back.
Once you start taking thyroid hormone replacement, your team will do occasional blood tests to find and maintain the right dose for you. When you’re on a stable dose, you’ll have these tests less frequently.
Radioactive Iodine Ablation
Iodine is a trace element found in some foods, like dairy products, seaweed, and iodized salt. It helps your thyroid make T3 and T4 hormones.
In thyroid cancer—especially if it has spread to your lymph nodes or other parts of your body—we will sometimes use a radioactive form of iodine in pill form to target and kill remaining thyroid cells and keep the cancer from coming back. Your team of thyroid experts will decide with you whether or not you will need radioactive iodine ablation and will discuss the risks and benefits with you.
Chemotherapy is almost never necessary for well-differentiated thyroid cancers. However, if you have thyroid lymphoma, anaplastic thyroid cancer, or advanced medullary thyroid cancer, you may have chemotherapy to shrink the tumor.
Chemotherapy uses medications to stop cancer growth and spread and to prevent cancer from recurring by causing rapidly dividing cancer cells to become damaged and die.
Chemotherapy is “systemic” medicine—it interferes with all fast-dividing cells in your body. This is why it causes side effects like hair loss. You’ll either get chemotherapy through an IV in our infusion center or perhaps through a pill, depending on the medication.
External Beam Radiation
External beam radiation is almost never necessary for well-differentiated thyroid cancer. However, if your thyroid cancer has spread to nearby areas, you may have radiation therapy to shrink the tumor. You might also have this treatment if you have medullary thyroid cancer, anaplastic thyroid cancer, or thyroid lymphoma, which can’t be treated with radioactive iodine.
Radiation therapy causes cancer cells to break or die by targeting the DNA with high-energy particles, such as X-rays, gamma rays, electron beams, or protons. Radiation oncology specialists direct these particles to the tumor site from outside of your body to precisely target cancer cells, often sparing nearby tissue. You might hear this called external beam radiation therapy.
Sometimes you’ll have chemotherapy and radiation at the same time, called chemoradiation.