How Thyroid Cancer Is Treated

Show Article Table of Contents

Treatment for thyroid cancer depends on the type you have, how large it is, your general health, and whether or not cancer has spread. Possible treatments include surgery, radioactive iodine therapy, radiation, chemotherapy, active surveillance, alcohol ablation, hormone therapy, and targeted drug therapy. Most cases of thyroid cancer can be cured with treatment.

Surgeries

The majority of people end up having thyroid surgery at some point to remove all or part of the thyroid and possibly nearby lymph nodes.

Thyroidectomy

Surgically removing the thyroid gland is called a thyroidectomy and it's the most common surgery used for thyroid cancer. Removing the entire thyroid is called a total thyroidectomy. In cases where your surgeon is unable to remove the whole thyroid but removes almost all it, this is a near-total thyroidectomy. If most of your thyroid is removed, it's a subtotal thyroidectomy.

This surgery is done through an incision that's a few inches long at the base of the front of your neck. After a thyroidectomy, you may have radioactive iodine therapy (see below) and you will need to start taking a thyroid hormone medication called levothyroxine, which goes by brand names Synthroid, Levoxyl, Levothroid, and others—to replace the missing thyroid hormones in your body now that your thyroid is gone.

If you're pregnant and you've been newly diagnosed with medullary or anaplastic thyroid cancer, the American Thyroid Association (ATA) recommends strongly considering a thyroidectomy during pregnancy because waiting until after the baby is born can create a negative outcome. Additionally, surgery may be necessary if, during the first 24 to 26 weeks of your pregnancy, your papillary thyroid cancer has grown substantially (meaning by 50 percent in volume and 20 percent in diameter in two dimensions). It also may be needed in cases where cancer has spread to your lymph nodes.

Lymph Node Removal

If your thyroid cancer has spread to the lymph nodes in your neck nearby, your doctor may remove these lymph nodes at the same time your thyroid is removed. Your doctor may also remove lymph nodes in your neck that has become enlarged to test them for cancer. Lymph node removal is particularly key for treating anaplastic or medullary thyroid cancer when you're a candidate for surgery. If you have papillary or follicular thyroid cancer and you have more than one or two enlarged lymph nodes, you may have a separate surgery to remove these.

Lobectomy

In the United States, about 80 percent of all thyroid cancers are papillary cancer, which is more likely to show up on only one side (lobe) of your thyroid and usually grows very slowly. The American Thyroid Association recommends a lobectomy, surgery to remove one lobe of the thyroid instead of the entire gland, for people in stage I or II of papillary cancer and for very small and/or very low-risk thyroid cancer.

Despite this recommendation, thyroidectomy is still the most commonly used surgery for any type of thyroid cancer. A lobectomy is also sometimes used to diagnose thyroid cancer if your biopsy was unclear and, occasionally, to treat follicular thyroid cancer.

If you have papillary thyroid cancer that fits within the following parameters, you may want to discuss having a lobectomy versus a thyroidectomy with your surgeon:

  • Your papillary thyroid cancer is stage I or II.
  • The tumor is located in only one lobe of your thyroid.
  • The tumor is 4 centimeters or less in size.

In a study of patients with biopsy results that were suspicious for papillary cancer, researchers found that a lobectomy was more effective, safer, and less expensive than a thyroidectomy. Because it can be performed on an outpatient basis and it's a shorter operation, a lobectomy is associated with a lower risk of complications and shorter recovery time, and patients report a better quality of life afterward.

Another potential advantage is that, since some of your thyroid is retained, you may not need to take thyroid hormone medication afterward.

Specialist-Driven Procedures

There are several different procedures to treat thyroid cancer, again, depending on the type you have, how big it is, and whether or not it has spread.

Radioactive Iodine Therapy

Radioactive iodine (RAI) therapy I-131, also known as radioiodine therapy, is circulated throughout your body in your bloodstream. It becomes concentrated in the thyroid gland, where the iodine destroys the gland’s cells. Radioactive iodine is mainly absorbed by the thyroid cells with little effect on other cells. It's used to treat follicular and papillary thyroid cancer and an overactive thyroid gland, a condition known as hyperthyroidism.

Radioactive iodine therapy may be given after a thyroidectomy to destroy any cancer cells that remain after surgery, to treat thyroid cancer that has spread, or to treat recurring thyroid cancer. You may need to have the treatment only once but, if needed, it can be repeated every three months until there is no sign of thyroid cancer.

Preparation: Before you have this treatment, you'll need to do some preparation.

  • Low-iodine diet: Your doctor will likely have you begin a low-iodine diet for one to two weeks before you have RAI treatment; too much iodine in your body will interfere with the results. You will need to eliminate things like iodized salt, red dye #3, cough medicine, seafood and fish, supplements containing iodine, dairy products, eggs, and soy. When you're given radioactive iodine, the iodine-starved thyroid cells absorb the RAI, destroying the cells.
  • Stop thyroid hormone medication: RAI also works best if your thyroid-stimulating hormone (TSH or thyrotropin) blood level is high because TSH promotes the absorption of the radioactive iodine into any residual cancer cells. If you've had a thyroidectomy, you may need to temporarily stop taking your thyroid hormone medication for several weeks before you have RAI. This pushes you into having low thyroid hormone levels (hypothyroidism), which means you may have some accompanying symptoms like fatigue, depression, weight gain, muscle aches, thinning hair, dry skin, mood swings, difficulty concentrating, delayed reflexes, headaches, constipation, and insomnia.
  • Thyrogen: Another way to raise TSH levels without having to stop your thyroid hormone medication is to get an injection of Thyrogen (thyrotropin alfa), a synthetic hormone that allows you to maintain proper thyroid function without the clearing out period that going off your medication can cause. Thyrogen is given in a series of shots over two days prior to RAI. During this time, you can continue taking your hormone medication without interruption. There may be a few side effects associated with the injections, mainly headache and nausea. Hives, itching, and flushing have also been known to occur, although these are considered rare. Thyrogen is not for everyone. Women who are pregnant or breastfeeding should not take it, nor should anyone who is allergic to any of the product’s ingredients.

Your doctor will talk to you about whether temporarily discontinuing your medications or getting Thyrogen injections is the best option for you.

What to expect: The procedure will take place in a hospital setting. You will be isolated from other patients for several days because the after-effects of the treatment cause you to become slightly radioactive.

You will ingest the radioactive iodine in either liquid form or as a capsule. You will need to refrain from eating so that your body can absorb the iodine. You will be able to eat and drink normally afterward, and you'll need to drink plenty of liquids to flush the radioactive iodine out of your system. When your radioactive levels have fallen, you will have a scan to determine where in your body the radioactivity has been absorbed.

Once your levels of radioactivity have fallen to a safe level, you'll be sent home with post-care instructions. You will need to avoid contact with small children and pregnant or breastfeeding women for a period of time.

Side effects: Depending on your age, overall health, and the amount of radioactive iodine you received, you may have one or more of the following short-term side effects:

Possible long-term side effects may include:

  • Lower sperm counts in men
  • Irregular menstrual cycles in women
  • Reduced level of blood cells produced
  • Risk of developing leukemia in the future
  • Dry eye

You will also be advised to wait at least six months after having RAI before getting pregnant. Researchers have not found an increase in infertility, miscarriage, stillbirth, neonatal mortality, congenital malformations, preterm birth, low birth weight, or death during the first year of life in babies whose mothers had RAI treatment for thyroid cancer.

External Radiation Therapy

External beam radiation therapy utilizes a machine that beams high-energy rays of radiation that are targeted to specific points on your body, which destroys or slows the growth of cancer cells. Similar to an X-ray, radiation is completely painless. It's usually administered for several minutes at a time, five days a week, for several weeks.

Radiation may be used when you're not a good candidate for surgery and radioactive iodine therapy hasn't worked, or if you have medullary or anaplastic thyroid cancer, which doesn't respond to radioactive iodine therapy. It's also sometimes used after you've had surgery if your doctor is concerned about cancer coming back.

Side effects: Radiation can destroy healthy tissue along with cancerous cells, which is why your doctor will do careful measurements to make sure the beams are as accurate as possible and that you are getting the correct dose. Other potential side effects include:

  • Redness to your skin similar to sunburn that typically fades
  • Difficulty swallowing
  • Dry mouth
  • Hoarseness
  • Fatigue

Chemotherapy

Chemotherapy, commonly referred to as chemo, uses strong drugs that are usually injected into your vein (intravenously) or into your muscle. Sometimes these drugs are taken by mouth. They travel throughout your entire body, searching out and destroying cancer cells.

Chemo isn't used for most types of thyroid cancers and it's not often needed. But if you have anaplastic thyroid cancer, you will likely have both chemo and radiation. It can also be helpful if your cancer has gotten into advanced stages and other treatments aren't working.

Side effects: Chemo side effects depend on the type of drug your doctor uses, as well as how much you take and for how long you take it. In general, common side effects include:

  • Hair loss
  • Sores in your mouth
  • Appetite loss
  • Vomiting
  • Nausea
  • Diarrhea
  • Less resistance to infections because you have fewer white blood cells to fight them off
  • Bruising and/or bleeding easily because your blood platelet count is low
  • Fatigue

Active Surveillance

For some small, low-risk, slow-growing papillary types of thyroid cancer, experts are beginning to recommend a new approach: active surveillance, also known as watchful waiting. Low-risk means that cancer has not spread and the tumor doesn't extend outside of the thyroid. The American Thyroid Association (ATA) has also endorsed active surveillance as an alternative to doing surgery right away in patients with low-risk papillary thyroid cancer, including low-risk papillary microcarcinoma, cancer that's less than 1 centimeter in size.

The best candidates for this approach are people who are diagnosed after the age of 50 years because their tumors tend to grow more slowly.

Benefits: This approach is beneficial for a number of reasons. First, thanks to technological advances, papillary thyroid cancer is detected far more often than it used to be. Second, the wait-and-see approach moves away from the tendency to immediately rush to surgery once a cancer diagnosis is made. Third, many people who are diagnosed with small papillary thyroid cancer won't need surgery for years, if ever.

Pregnancy: Active surveillance is recommended by the ATA for pregnant women who have been diagnosed with papillary thyroid cancer early in their pregnancy.

The cancer should be routinely monitored with ultrasound. If it starts to grow 50 percent in volume and 20 percent in diameter in two dimensions by 24 to 26 weeks' gestation, or if it has spread to your lymph nodes, a thyroidectomy should be done in the second trimester—a time that has the least risks for both you and your baby. However, if the cancer remains stable or it's diagnosed in the second half of your pregnancy, surgery can be put off until after you have your baby.

For women who have been diagnosed with papillary microcarcinoma (a tumor that's less than 1 centimeter in size) and are on active surveillance, ultrasound monitoring should be done every trimester to check for growth or spreading.

Research: One study monitored a group of patients who had very small—less than 1.5 millimeters in size—papillary thyroid tumors to see how they grew. Their tumor sizes were measured using three-dimensional ultrasound every six months to every year. After five years, only 12 percent of the tumors grew to 3 millimeters or more in size and the cancer didn't spread at all in the patients studied during active surveillance.

The three-dimensional ultrasound was noted as being key in making active surveillance a viable option. Having a tumor measured with the 3D ultrasound every six months for the first two years of active surveillance establishes a growth rate. If the tumor starts growing fast, surgery can be initiated. In this study, most of the tumors didn't grow much or at all, further evidence that active surveillance should be offered to patients who meet the low-risk, small tumor guidelines.

Points to consider: Keep in mind that, in order to use active surveillance, you need to have a specialized and skilled medical team that has experience with this method. Your outcome may not be as good if you receive care outside of medical providers or centers that have knowledge of the active surveillance protocols. You will also need to have regular three-dimensional ultrasound scans, as well as regular checkups to keep an eye on your tumor.

Alcohol Ablation

Also known as ethanol ablation and percutaneous ethanol injection (PEI), alcohol ablation is a newer, cost-effective technique that's sometimes used for small papillary thyroid cancer. With an ultrasound machine as a visual guide, the cancerous nodule is injected with alcohol, destroying the cancer cells. Alcohol ablation may be performed when your cancer is located in areas that are hard to access through surgery or if you have recurrent thyroid cancer in small areas of your neck.

This procedure is not routinely used and studies are still being conducted on its overall effectiveness, especially since many people worldwide don't have the means or access to surgical treatment. Though larger, better-quality studies need to be done, one JAMA study concluded that alcohol ablation has the potential to become a widely used, effective, and accepted treatment method for certain people with papillary thyroid cancer who aren't good surgery candidates or who want to avoid further surgery.

Prescriptions

There are two types of prescription drugs used to treat thyroid cancer: thyroid hormone therapy, which is very common, and targeted drug therapy, used much less often.

Thyroid Hormone Therapy

After you have a thyroidectomy, and often after you have a lobectomy, you will need daily thyroid hormone medication for the rest of your life. Synthroid (levothyroxine) replaces the thyroid hormone your body no longer makes since you've had your thyroid removed, and helps keep your metabolism balanced. It also works to keep your TSH levels down, which in turn reduces your chances of the cancer coming back since high TSH levels can trigger growth in any cancer cells that may be left.

If you have papillary or follicular thyroid cancer and your doctor thinks you're at high risk for the cancer to return, you may be prescribed more thyroid hormone medication than normal because this keeps your TSH level even lower. However, being on a higher dose long-term does carry some risk, such as irregular heartbeat and osteoporosis (weakened bones), so studies are being done on how long patients should stay on this type of suppression therapy.

Your doctor will closely monitor the amount of thyroid hormone in your blood with blood tests, especially if you're on a higher dose of levothyroxine until the right dosage is found. After that, you'll have less frequent blood tests.

Side effects: Levothyroxine has many potential side effects, some or all of which may go away in time, including:

  • Weight loss
  • Shakiness or tremor
  • Headache
  • Nausea
  • Vomiting
  • Diarrhea
  • Abdominal cramps
  • Feeling nervous
  • Feeling irritable
  • Difficulty sleeping
  • Sweating more than normal
  • Increased appetite
  • Fever
  • Menstrual changes
  • Feeling sensitive to heat
  • Temporary hair loss when you first start levothyroxine (more common in children)

If you experience chest pain or a fast or irregular heartbeat while taking levothyroxine, call your doctor right away.

Targeted Drug Therapy

There are newer drugs being developed that work by attacking certain targets in your cancer cells that cause them to change, grow, and divide. This type of treatment is more specific than chemotherapy, which destroys all fast-growing cells, including healthy ones, and it's typically used for people with advanced thyroid cancer.

For papillary and follicular thyroid cancer: Most people with papillary or follicular thyroid cancer respond well to surgery and radioiodine therapy, but for those who don't, the targeted drugs Nexavar (sorafenib) or Lenvima (lenvatinib) may help stop the cancer from progressing. 

Known as tyrosine kinase inhibitors, these drugs keep tumors from growing by blocking certain growth-enhancing proteins they make and also sometimes cutting off the ability of tumors to develop new blood vessels.

Common side effects may include fatigue; rash; appetite loss; nausea; diarrhea; high blood pressure; and redness, swelling, pain, or blisters on the palms of your hands or the soles of your feet.

For medullary thyroid cancer: Since typical treatments for thyroid cancer like radioactive iodine therapy don't work well for medullary thyroid cancer, targeted drug therapy may be particularly helpful.

The drugs that treat this type of cancer are Caprelsa (vandetanib) and Cometriq (cabozantinib), both of which have been shown to help stop tumors from growing for about six and seven months respectively. They are both pills taken by mouth once a day. It's still unclear whether these drugs help people with thyroid cancer live longer.

Some of the common side effects of Caprelsa are diarrhea, rash, nausea, high blood pressure, fatigue, headache, appetite loss, and abdominal pain. Though it's rare, Caprelsa can also create serious heart rhythm and infection issues that may cause death, which is why doctors have to be specially trained in order to prescribe it.

Common side effects of Cometriq include constipation; diarrhea; nausea; abdominal pain; sores in your mouth; appetite loss; weight loss; fatigue; high blood pressure; hair color loss; and redness, swelling, pain, or blisters on the palms of your hands or the soles of your feet. Rare serious side effects include severe bleeding and developing holes in your intestine.

View Article Sources