Follicular Thyroid Cancer: Introduction

Since the 1970’s, the incidence of thyroid cancer has doubled. Until recently, thyroid cancer was the fastest growing cancer in the United States, mainly due to our ability to detect these cancers so well (Ultrasound, CT scan, MRI, etc.). Thyroid cancer is the 5th most common cancer in women. Overall, the 5-year survival rate for people with thyroid cancer is 98%, with long-term survival being 95% or higher.

There are 4 main types of thyroid cancer, and follicular thyroid cancer is the 2^nd most common type. Follicular thyroid cancer accounts for roughly 10-15% of all thyroid cancers. This cancer is more common in women than men at a 3:1 ratio. Peak incidence is between the ages of 40-60 years. Risks for developing follicular thyroid cancer are iodine deficiency, significant radiation exposure to the head/neck area or chest, typically from treatment of another cancer (lymphoma, breast cancer, etc.) or exposure from a nuclear disaster, obesity, and a strong family history of thyroid cancer or a thyroid cancer syndrome. Overall cure rate approaches 95%, for patients with follicular thyroid cancer, particularly in the hands of expert surgeons at specialized, high-volume thyroid centers.

Follicular Thyroid Cancer: Top 4 Things to Know

Below I will discuss the 4 most important facts to know about follicular thyroid cancer, including thyroid cancer surgery, further treatment, and follow-up.

Learn more about all types of thyroid cancer and expert thyroid care.

#1 Thing to Know About Follicular Thyroid Cancer: Thyroid cancer surgery is the treatment

Thyroid surgery is the mainstay of treating thyroid cancer. There are 2 main types of thyroid removal (thyroidectomy): thyroid lobectomy (removal of half of the thyroid) and total thyroidectomy (removal of the entire thyroid). Many cancerous thyroid nodules can be treated by removal of half the thyroid along with the lymph nodes that are located behind and around the thyroid. This is done less frequently for follicular thyroid cancer, but still is an option in some cases (i.e. small cancer confined to one side of the thyroid). Numerous studies have shown that up to 20%- 30% of thyroid cancers have spread to lymph nodes at the time of diagnosis and surgery. Expert evaluation and complete removal of all cancer with the first surgery are extremely important to avoid complications and leaving cancer behind.

In most instances of follicular thyroid cancer, total thyroidectomy is needed. This is true especially for cancers that are large, located in both halves of the thyroid, or have spread to lymph nodes in the neck. Again, removal of the lymph nodes behind and around the thyroid in the middle of the neck at a minimum is important to ensure the follicular thyroid cancer is completely cured. Complete thyroid removal is even riskier than thyroid surgery for half the thyroid. This is because both sides of the neck are worked on, exposing all 4 parathyroid glands (calcium control glands) as well as all the nerves to the voice box to potential damage. Thus, total thyroid removal should only be done by high-volume, experienced surgeons at busy centers such as ours.

Finally, follicular thyroid cancer is less likely to spread to lymph nodes than papillary thyroid cancer, but more likely to spread to other areas of the body. Follicular thyroid cancer that has spread to lymph nodes in the side of the neck is treated by removing the whole thyroid (total thyroidectomy) along with lymph node dissection (neck dissection). This thyroid surgery is done for thyroid cancers that have spread to lymph nodes in the side of the neck (on the left, right, or both) or to the lymph nodes in the center of the neck around and behind the thyroid. Surgery for follicular thyroid cancer must address the lymph node areas that are known to contain cancer as well as those that are at significant risk of having thyroid cancer.

Learn more about thyroidectomy for thyroid cancer and the 3 best operations for thyroid cancer.

#2 Thing to Know About Follicular Thyroid Cancer: You will survive

The 5-year survival rate for follicular thyroid cancer that has not spread outside of the thyroid gland (localized) is almost 100%. The 5-year survival rate for follicular thyroid cancer that has only spread to lymph nodes or tissue in the neck (regional) is 98%. If there is distant spread to other parts of the body (outside of the neck), it is called metastatic disease. The 5-year survival rate for metastatic follicular thyroid cancer is 63%, which is excellent compared to many other types of cancer. As seen above, this type of thyroid cancer has a high cure rate—10-year survival rates for all patients with follicular thyroid cancer estimated at roughly 85%. Finally, the overall cure rate for follicular thyroid cancer approaches 95%.

Your quality of life is very unlikely to be negatively affected by thyroid cancer surgery done correctly in the hands of experts. You may have to take thyroid hormone medication after thyroid removal. As long as you are compliant with the necessary medication and follow-up, then their thyroid levels should be appropriate. If your thyroid levels are where they should be, then thyroid medication or thyroid cancer surgery will NOT be the cause of weight gain, fatigue, hair loss, etc. that everyone is concerned about. The reality is, almost everyone on thyroid hormone medication will do great as long as they take the medication as directed, get their thyroid levels checked 1-2 times yearly at a minimum, and maintain a healthy lifestyle.

You can beat follicular thyroid cancer, and your life expectancy will be the same in most cases. Learn more about finding the best thyroid cancer surgeon for your treatment.

#3 Thing to Know About Follicular Thyroid Cancer: Most patients do not need further treatment

Most often, excellent and thorough thyroid cancer surgery is the only treatment needed for follicular thyroid cancer. Traditional chemotherapy is never used. External or beam radiation therapy is very rarely indicated for further follicular thyroid cancer treatment. Follicular thyroid cancer diagnosis alone is not an indication for further therapy after thyroid surgery.

The most commonly used treatment after thyroid cancer surgery, however, is radioactive iodine (RAI). This treatment works better the younger the patient is. Iodine is used by normal thyroid cells to make thyroid hormone. Thyroid cancers can possess the same type of key hole on the surface of their cell called a symporter (or pump) that allows iodine to be taken into the cell. Although follicular thyroid cancer rarely produces any significant amounts of thyroid hormone itself, it frequently maintains this iodine pump and ability to take up iodine. In the treatment of thyroid cancer, this can be taken advantage of by having the patient swallow an iodine pill that has been radioactively charged.

In brief, the patient swallows a radioactive iodine form of iodine called iodine- 131 (I-131) in a liquid or pill (capsule) form. The radioactive iodine (RAI) is absorbed and circulated throughout the body in bloodstream. Follicular thyroid cancer cells can pick up the radioactive iodine (if they possess the symporter for iodine) wherever they are located in the body. Once taken into the thyroid cancer cells, the radioactive iodine delivers a local radiation treatment in the area where the iodine is concentrated.

Learn more about radioactive iodine for follicular thyroid cancer.

#4 Thing to Know About Follicular Thyroid Cancer: Follow-up is necessary, but not overwhelming

After expert thyroid surgery to cure your follicular thyroid cancer, follow-up is important, but not unmanageable. At the Clayman Thyroid Center, we feel that thyroid cancer patient follow-up is best managed by an endocrinologist with defined expertise in the evaluation, management, and follow-up of thyroid cancer patients. Communication between the endocrinologist, surgeon, radiologist, and other members of the thyroid cancer team is critical. This is the absolute foundation of thyroid cancer treatment at the Clayman Thyroid Center.

After surgery for follicular thyroid cancer, your thyroid hormone levels should be checked in 4-6 weeks to see if thyroid hormone medication is needed or if your dose should be adjusted. You should have a complete history and physical exam along with an expert ultrasound done 6 months after thyroid cancer surgery and yearly after that. The following blood tests are always done routinely (typically twice yearly after the first year) for surveillance and monitoring: Free T4 level (Blood level of the major hormone normally produced by the thyroid gland or provided by thyroid hormone medication), TSH (Thyroid Stimulating Hormone), Thyroglobulin (a protein made by thyroid cells and follicular thyroid cancer cells in many cases), Thyroglobulin antibody (An antibody that recognizes the normal thyroglobulin protein as being "abnormal". These are not harmful, but are a sign of an autoimmune disease where the body recognizes itself as being abnormal. The presence of Thyroglobulin antibodies makes Thyroglobulin a largely useless blood test for monitoring thyroid cancer).

Imaging tests such CT scan, PET/CT scan, and radioiodine scan are used if there is an aggressive follicular thyroid cancer with high risk of coming back (recurrence) or if there is evidence of a recurrence. In these cases, further imaging studies are done to look at the neck and other areas of the body where cancer may spread. The need for these tests should be determined and ordered by experienced thyroid cancer experts.

Learn more about about thyroid cancer follow-up labs, imaging tests, and surveillance.

Summary

Follicular thyroid cancer is the 2^nd most common thyroid cancer by far. Fortunately, this cancer is very curable and very unlikely impacts a patient’s life expectancy. Expert thyroid cancer surgery done at a center like ours is the first and most step in the cure of your follicular thyroid cancer. Additional medical treatment is often unnecessary. While follow-up with an expert thyroid cancer team is paramount, the surveillance is not overwhelming or difficult to manage.

Our team of thyroid cancer experts is here to help and guide you every step along the way and will be there for you after your thyroid surgery for follicular thyroid cancer. To learn more and become a patient, please see our resources below.

Additional Resources

• Become our patient by filling out the form at this link. 
• Learn more about The Clayman Thyroid Center here. 
• Learn more about our sister surgeons at the Scarless Thyroid Surgery Center, Norman Parathyroid Center, and Carling Adrenal Center
• Learn more about the Hospital for Endocrine Surgery.