Treatment of Thyroid Cancer, by Type and Stage

The type of treatment your cancer care team recommends will depend on the type and stage of your thyroid cancer, your overall health, and your personal preferences. Talk to your doctor if you have any questions about the treatment plan they recommend for you.

Treating papillary thyroid cancer and its variants

Most papillary thyroid cancers are treated with surgery. This is most often a total thyroidectomy (in which the entire thyroid is removed), although some small tumors can be treated with a lobectomy (just removing the side of the thyroid containing the tumor).

In some cases, people with very small thyroid cancers may choose to have the cancer watched closely with regular ultrasounds, rather than having surgery right away. This is known as active surveillance. If anything changes (such as if the tumor grows larger), surgery can be done at that point.

For people who do have surgery, if the nearby lymph nodes are enlarged or show signs of cancer spread, they will also be removed.

Even if the lymph nodes aren’t enlarged, some doctors might recommend a central compartment neck dissection (removal of lymph nodes in the middle of the neck next to the thyroid), especially if the cancer is larger or has other concerning features. This might lower the risk of cancer coming back in the neck area.

Because removing the lymph nodes allows them to be checked for cancer, this surgery also makes it easier to accurately stage the cancer.

If cancer has spread to other neck lymph nodes, a modified radical neck dissection is often done. This involves removing even more lymph nodes, including nodes on the side of the neck.

Treatment after surgery depends on the risk of the cancer coming back (which is based on the stage of the cancer and other factors).

For cancers with a lower risk of coming back, no further treatment is usually needed.

For cancers with a higher risk of coming back (or cancers that are not removed completely with surgery), radioactive iodine (RAI) treatment is often given several weeks after thyroidectomy. The goal is to destroy any remaining thyroid tissue and to try to treat any cancer remaining in the body.

If any remaining cancer does not respond to RAI, other treatments such as external beam radiation therapy, targeted therapy drugs (such as those discussed below), or chemotherapy might be options.

People who have had a thyroidectomy will need to take daily thyroid hormone therapy (levothyroxine pills). If RAI treatment is planned, the start of hormone therapy may be delayed until the treatment is finished.

Treating recurrent papillary thyroid cancer

If papillary thyroid cancer comes back (recurs) after the initial treatment, it might be found by blood tests, or by imaging tests such as ultrasound or radioiodine scans. The way the recurrence is treated depends mainly on where the cancer is growing, although other factors can be important as well.

If cancer comes back in the neck and if the tumor appears to be resectable (removable), surgery is often done.

If the cancer shows up on a radioiodine scan (meaning the cancer cells are taking up iodine), radioactive iodine (RAI) therapy may be used, either alone or with surgery.

If the cancer does not show up on the radioiodine scan but is found by other imaging tests (such as an MRI or PET scan), external radiation may be used.

If the cancer has spread and RAI and other treatments are not helpful, targeted therapy drugs such as lenvatinib (Lenvima) or sorafenib (Nexavar) may be an option. If these drugs are no longer working, cabozantinib (Cabometyx) might be an option. If the cancer cells have changes in certain genes (such as the RET or NTRK genes), other targeted drugs might be helpful as well.

If the cancer cells have certain other changes (such as having many gene mutations), treatment with a type of medicine known as an immune checkpoint inhibitor might be an option as well.

Chemotherapy might also be an option at some point if other treatments aren’t working.

Because these cancers can be hard to treat, taking part in a clinical trial of newer treatments is another choice.

Treating follicular thyroid cancer

Follicular thyroid cancer is usually treated in much the same way as papillary thyroid cancer (described above).

Most often, it’s not clear that a thyroid tumor is a follicular cancer based on the results of an FNA biopsy alone. If this is the case, “follicular neoplasm” might be listed as the diagnosis.

Most follicular neoplasms actually turn out not to be cancer. But to be sure, the next step is usually surgery to remove only the half of the thyroid gland that has the tumor (a lobectomy). This lets doctors look at the tumor more closely.

If the tumor turns out to be a follicular cancer, a second operation (called a completion thyroidectomy) is usually done to remove the rest of the thyroid .

If you only want one operation, your doctor might just remove your whole thyroid gland (a total thyroidectomy) during the first surgery. Still, for most people, this isn’t really needed.

If there are signs the cancer has spread before surgery, then the tumor is most likely cancer. In this case, a total thyroidectomy will be done.

When the thyroidectomy is done, some nearby lymph nodes in the neck might be removed and checked for cancer. If cancer has spread to lymph nodes, a central compartment or modified neck dissection (surgical removal of lymph nodes from the neck) may be done.

People who have had a thyroidectomy will need to take daily thyroid hormone therapy, although it is often not started right away.

Radioiodine scanning is usually done after surgery to look for any areas in the body still taking up iodine. If the scan shows cancer spread to nearby lymph nodes or to distant parts of the body, this can then be treated with radioactive iodine (RAI).

For cancers that don’t take up iodine, external beam radiation therapy may help treat the tumor or prevent it from growing back in the neck.

If RAI isn’t helpful, cancer that has spread to distant parts of the body such as the lungs or liver may need to be treated with external beam radiation therapy, targeted therapy drugs (such as those discussed below), or chemotherapy.

Treating recurrent follicular thyroid cancer

If follicular thyroid cancer comes back (recurs) after the initial treatment is finished, it might be found by blood tests, or by imaging tests such as ultrasound or radioiodine scans. The way this recurrence is treated depends mainly on where the cancer is growing, although other factors can be important as well.

If cancer comes back in the neck and if the tumor appears to be resectable (removable), surgery is often done.

If the cancer shows up on a radioiodine scan (meaning the cancer cells are taking up iodine), radioactive iodine (RAI) therapy may be used, either alone or with surgery.

If the cancer does not show up on the radioiodine scan but is found by other imaging tests (such as an MRI or PET scan), external radiation may be used.

If the cancer has spread to several places and RAI was not helpful, targeted therapy with drugs such as lenvatinib (Lenvima) or sorafenib (Nexavar) is often tried first. If these drugs are no longer working, cabozantinib (Cabometyx) might be an option. If the cancer cells have changes in certain genes (such as the RET or NTRK genes) other targeted drugs might be helpful as well.

If the cancer cells have certain other changes (such as having many gene mutations), treatment with a type of medicine known as an immune checkpoint inhibitor might be an option as well.

Chemotherapy might also be an option at some point if other treatments aren’t working.

Because these cancers can be hard to treat, taking part in a clinical trial of newer treatments is another choice.

Treating medullary thyroid cancer

If you are diagnosed with medullary thyroid cancer (MTC), you will typically be advised to have genetic testing (see below) to look for inherited changes in the RET gene. These changes are linked with multiple endocrine neoplasia type 2 (MEN2) (see Thyroid Cancer Risk Factors).

If you haven’t had genetic testing, or if your test results aren’t yet available, you will most likely be tested for certain other tumors before you have surgery. These tumors (such as pheochromocytoma and parathyroid tumors) can occur in people with MEN2.

Screening for pheochromocytoma is particularly important, because anesthesia and surgery can be very dangerous for people with these tumors. If surgeons and anesthesiologists know about the tumors ahead of time, they can treat the person with medicines before and during surgery to make the operation safe.

Treating stages I and II MTC

Total thyroidectomy (removing the entire thyroid gland) is the main treatment for stage I or stage II MTC, and it can often cure these cancers. Nearby lymph nodes in the neck are usually removed as well.

Because the thyroid gland is removed, you will need thyroid hormone therapy to keep you healthy, although it doesn’t reduce the risk that the cancer will come back.

Because MTC cells don't take up radioactive iodine, radioactive iodine (RAI) therapy isn’t helpful in treating MTC.

Treating stages III and IV MTC

Surgery for these cancers is the same as for stage I and II cancers (usually after screening for MEN2 syndrome and pheochromocytoma). Thyroid hormone therapy is needed afterward.

If the tumor is extensive and invades many nearby tissues, or if it can’t be removed completely, external beam radiation therapy may be given after surgery to try to reduce the chance of the cancer coming back in the neck.

For cancers that have spread to distant parts of the body, surgery, radiation therapy, or similar treatments may be used if possible. If these treatments can’t be done, targeted drugs such as vandetanib (Caprelsa) or cabozantinib (Cometriq) may be tried. Other targeted drugs might be helpful as well, especially if the cancer cells have changes in certain genes (such as the RET gene). Chemotherapy may be another option.

Because these cancers can be hard to treat, another option is taking part in a clinical trial of newer treatments.

Treating recurrent MTC

If the cancer recurs in the neck or elsewhere, surgery, external radiation therapy, targeted therapy drugs (such as vandetanib or cabozantinib), or chemotherapy may be options. Clinical trials of new treatments may also be an option.

Genetic testing in people with medullary thyroid cancer

If you are told that you have MTC, talk to your doctor about genetic counseling and testing. This is important even if you are the first person in your family to be diagnosed with the disease. Genetic testing can check your cells for mutations in the RET gene. These mutations are seen in people with the MEN2 syndromes, including familial MTC.

If you have one of these mutations, it’s important that close family members (children, siblings, and parents) are tested as well.

Almost all children and adults with mutations in this gene will develop MTC at some point. Because of this, most doctors agree that anyone who has a RET gene mutation should have their thyroid removed to prevent MTC. This surgery should be done soon after getting the test results. This includes children, since some hereditary forms of MTC can affect children.

A total thyroidectomy can prevent this cancer in people with RET mutations who have not yet developed it. If this is done, lifelong thyroid hormone replacement will be needed.

Treating anaplastic thyroid cancer

Surgery is often not as helpful for anaplastic thyroid cancer as it is for other types of thyroid cancer.

If the cancer is confined to the area around the thyroid, which is rare, the entire thyroid and nearby lymph nodes may be removed. The goal of this surgery is to remove as much cancer in the neck area as possible, ideally leaving no cancer behind. But because of the way anaplastic cancer spreads, this is often very difficult.

Because anaplastic thyroid cancer cells don’t take up radioactive iodine, radioactive iodine (RAI) therapy isn’t helpful in treating this type of cancer.

External beam radiation therapy may be used alone or combined with chemotherapy:

• To try to shrink the cancer before surgery, increasing the chance of removing it completely
• After surgery, to try to control any cancer that remains in the neck
• When the tumor is too large or widespread to be treated with surgery

If your cancer is causing you to have trouble breathing (or if this may eventually happen), a surgery called a tracheostomy might be done. During a tracheostomy, the surgeon creates a hole in the front of your neck and into your windpipe to bypass the tumor and allow you to breathe more comfortably.

For cancers that have spread, chemotherapy alone can be used. If the cancer cells have changes in certain genes, treatment with targeted drugs might be helpful. For example:

• Dabrafenib (Tafinlar) and trametinib (Mekinist) can be used to treat cancers with certain BRAF gene changes.
• Selpercatinib (Retevmo) or pralsetinib (Gavreto) can be used to treat cancers with certain RET gene changes.
• Larotrectinib (Vitrakvi), entrectinib (Rozlytrek), or repotrectinib (Augtyro) can be used to treat cancers with NTRK gene changes.
• Crizotinib (Xalkori) and ceritinib (Zykadia) might be options to treat cancers with ALK gene changes (although these drugs aren’t FDA-approved specifically to treat thyroid cancer). 

Because these cancers can be hard to treat, clinical trials of newer treatments might be a good option for some people.