Treatment for Follicular and Hurthle Cell Carcinomas

If you have Stage I to IV follicular or Hürthle cell carcinoma, you will probably be treated with total thyroidectomy. If your cancer has spread to the lymph nodes (tiny bean-shaped organs throughout the body that help fight infections), your doctor might recommend that you have a modified radical or radical neck dissection in addition to the thyroidectomy.

• Total thyroidectomy - The surgeon removes the entire thyroid, and sometimes nearby lymph nodes, through an incision in the neck. In some rare cases, the surgeon also takes out other tissues in the neck that have been affected by the cancer.
• Neck dissection - The surgeon removes lymph nodes in the front and side of the neck that may contain cancer.
• Modified radical - The surgeon removes all of the lymph nodes on one side of the neck from the lower edge of the jaw to the upper edge of the collarbone. However, the surgeon does not take out sections of muscle, nerve, and the large veins in the neck.
• Radical -  The surgeon removes all of the lymph nodes on one side of the neck from the lower edge of the jaw to the upper edge of the collarbone. The surgeon also takes out sections of muscle, nerve, and the large veins in the neck.

You will probably also be treated with radioactive iodine after the surgery. This treatment can destroy cancer cells not removed by surgery and those that have spread beyond the thyroid.

• Radioactive iodine (radioiodine) - Radioiodine can destroy the rest of the thyroid gland and thyroid cancer (if the cancer takes up iodine) without affecting the rest of your body. Radioiodine is usually given as a capsule or in liquid form about 6 weeks after surgery. If you receive the usual dose, you will probably stay in the hospital for about 2 or 3 days while you are treated. If you receive a small dose, you will probably not have to stay in the hospital.

If your metastases cannot be treated successfully with radioactive iodine, you might be treated with external beam radiation therapy, which uses high-energy x-rays or other types of radiation to kill cancer cells. It is sometimes used to reduce the chance that the disease will come back (recur) in the neck.

• External beam radiation therapy (EBRT) - Radiation from a high-energy x-ray machine (linear accelerator) outside the body is focused on the cancer cells. Most people are treated with EBRT for a few minutes 5 days a week for a few weeks or months as an outpatient.

Regardless of the type of surgery you had, you will be treated with thyroid hormone after surgery. However, if your doctor plans to treat you with radioactive iodine, you might not start taking thyroid hormone until after you finish your radioactive iodine treatments.

• Thyroid hormone replacement - These pills can give your body the natural thyroid hormone it can no longer make on its own. The thyroid hormone pills can also slow down the growth of any cancer cells that are left in your body. The generic name of the hormone is levothyroxine sodium. It is sold as Synthroid^®, Levoxyl^®, Levothroid^®, Unithroid^®, and other brand names.

This content has been reviewed and approved by Myo Thant, MD. 

Well Differentiated Thyroid Cancer Follow Up

Papillary and/or Follicular thyroid cancer will recur or persist in about 25% of patients, and 80% of these recurrences will be in the neck. Recurrence occurs most commonly in the first 2 years after thyroidectomy. In papillary thyroid cancer, however, recurrence can occur up to 45 years after surgery, whereas virtually all patients with follicular and Hürthle cell cancer recur before 12 years after surgery.

• The current recommendations for postoperative follow-up of well-differentiated thyroid cancer, except for very low-risk patients, are thyroid remnant ablation and thyroid stimulating hormone (TSH) suppression. 

• Radioiodine ablation is recommended for patients with papillary thyroid cancers larger than 1.5cm, multifocal tumors, and for those with lymph node metastases. 

• Invasive follicular and Hürthle cell cancer also warrant radioiodine therapy.  

• Doctors routinely recommend the  use 30 to 50 mCi of radioiodine in low risk and 100 to 200 mCi of radioiodine in high-risk patients. 

• The initial radioiodine treatment should be performed under hormone withdrawal, or with recombinant TSH stimulation 6-8 weeks post operatively in an iodine deficient patient. 

• Patients should have a thyroid hormone levels (TSH, T3, T4, Thyroglobulin) measured as well  pregnancy test prior to 131-Iodine scanning and ablation therapy, and post-treatment imaging. 

TSH  is known to stimulate tumor growth, invasion, angiogenesis, and thyroglobulin secretion. Therefore post operatively patients are placed on thyroid hormone replacement therapy. 

• In  low-risk patients doctors maintain the serum TSH level just below the lower limit of the normal range between 0.1 and 0.4 mU/ mL. 

• In high-risk patients the dosage is adjusted to maintain a serum TSH level less than 0.1 mU/ mL, as this has been reported to improve tumor free survival. 

Adverse effects of TSH suppression may include:  

• subclinical thyrotoxicosis 
• exacerbation of angina 
• atrial fibrillation
• osteoporosis in postmenopausal women

External beam radiation and chemotherapy have a limited role in the postoperative management of well differentiated thyroid carcinoma patients. 

• External beam radiation is used infrequently in the management of thyroid cancer except as a palliative treatment for locally advanced unresectable disease, positive tumor margins, or recurrent disease after re-resection. 

• Chemotherapy has shown only minimal benefit in the treatment of well-differentiated thyroid cancer. New clinical trials have recently become available.

Follow-up is different for patients at low, intermediate, and high risk of having persistent or recurrent disease. 

• Low risk patients are defined as patients with no local or distant metastases, complete resection of tumor contained within the thyroid with no locoregional invasion, tumor without aggressive histology, and if radioiodine was given there was no uptake outside of the thyroid bed. 

• Intermediate risk patients have microscopic invasion of tumor into the peri-thyroidal soft tissue at initial surgery or tumor with aggressive histology or vascular invasion. 

• High-risk patients have macroscopic tumor invasion, incomplete tumor resection, distant metastases, or radioiodine uptake outside the thyroid bed on the post-treatment scan after thyroid remnant ablation.

The absence of persistent disease in patients that have undergone at least a total thyroidectomy and thyroid remnant ablation comprises of no clinical evidence of tumor, no imaging evidence of tumor, and undetectable serum thyroglobulin levels during TSH suppression and stimulation in the absence of interfering antibodies.

All patients with a history of well-differentiated thyroid cancer should have yearly cervical ultrasound scanning, thyroglobulin and thyroglobulin antibodies. 

• Approximately 20% of patients who are clinically disease free with serum thyroglobulin levels less than 2 ng/mL during thyroid hormone suppression will have a thyroglobulin level greater than 5 ng/mL after rhTSH or thyroid hormone withdrawal. One third of this group will have persistent disease identified on imaging studies. Therefore, a serum thyroglobulin level above 5 ng/mL after rhTSH stimulation is highly sensitive in identifying patients with persistent disease. Furthermore, the clinical significance of minimally detectable thyroglobulin levels is unclear, especially if only detected after TSH stimulation. 

• Approximately 25% of patients with thyroid cancer have antithyroglobulin antibodies making follow-up with thyroglobulin insensitive. In this group serial serum antithyroglobulin antibody measurements may serve as an imprecise surrogate marker to detect recurrence among these patients. Accurate surveillance for possible recurrence and treatment in patients thought to be free of disease is a major goal of long-term follow-up.

SOURCE: Weill Cornell Medical College

Diagnostic Testing for Thyroid Cancer Basics

The Following Diagnostic Tests and Procedures  that examine the thyroid, neck, and blood are used to detect (find) and diagnose thyroid cancer.

• Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or swelling in the neck, voice box, and lymph nodes, and anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.

• Laryngoscopy: A procedure in which the doctor checks the larynx (voice box) with a mirror or with a laryngoscope. A laryngoscope is a thin, tube-like instrument with a light and a lens for viewing. A thyroid tumor may press on vocal cords. The laryngoscopy is done to see if the vocal cords are moving normally.

• Blood hormone studies: A procedure in which a blood sample is checked to measure the amounts of certain hormones released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease in the organ or tissue that makes it. The blood may be checked for abnormal levels of thyroid-stimulating hormone (TSH). TSH is made by the pituitary gland in the brain. It stimulates the release of thyroid hormone and controls how fast follicular thyroid cells grow. The blood may also be checked for high levels of the hormone calcitonin.

• Blood chemistry studies: A procedure in which a blood sample is checked to measure the amounts of certain substances, such as calcium, released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease in the organ or tissue that makes it.

• Radioactive iodine scan (RAI scan): A procedure to find areas in the body where thyroid cancer cells may be dividing quickly. Radioactive iodine (RAI) is used because only thyroid cells take up iodine. A very small amount of RAI is swallowed, travels through the blood, and collects in thyroid tissue and thyroid cancer cells anywhere in the body. Abnormal thyroid cells take up less iodine than normal thyroid tissue. Areas that do not absorb the iodine normally (cold spots) show up lighter in the picture made by the scan. Cold spots can be either benign (not cancer) or malignant, so a biopsy is done to find out if they are cancer.

• Ultrasound exam: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. The picture can be printed to be looked at later. This procedure can show the size of a thyroid tumor and whether it is solid or a fluid-filled cyst. Ultrasound may be used to guide a fine-needle aspiration biopsy.

• CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.

• MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).

• PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.

• Fine-needle aspiration biopsy of the thyroid: The removal of thyroid tissue using a thin needle. The needle is inserted through the skin into the thyroid. Several tissue samples are removed from different parts of the thyroid. A pathologist views the tissue samples under a microscope to look for cancer cells. Because the type of thyroid cancer can be hard to diagnose, patients should ask to have biopsy samples checked by a pathologist who has experience diagnosing thyroid cancer.

• Surgical biopsy: The removal of the thyroid nodule or one lobe of the thyroid during surgery so the cells and tissues can be viewed under a microscope by a pathologist to check for signs of cancer. Because the type of thyroid cancer can be hard to diagnose, patients should ask to have biopsy samples checked by a pathologist who has experience diagnosing thyroid cancer.

MEDICAL REVIEW: 02/12/2012

Hurthle Cell Thyroid Tumor: A Different Type of Thyroid Cancer

Hurthle cell thyroid cancer is usually classified with follicular thyroid cancer, although it really is a distinct kind of tumor. It is an unusual tumor, making up about 4% of thyroid cancers and is only about one-fourth as common as follicular cancers.

• What is a Hurthle Cell?  A Hurthle cell is a kind of thyroid cell which has a distinctive look: under the microscope it is bigger than a follicular cell and has pink-staining cellular material.

• Is the Hurthle Cell Tumor Benign or Malignant?  Like follicular tumors, there are benign Hurthle cell tumors and malignant Hurthle cell tumors, and the pathologist tells the difference between them based on invasion of the capsule and the blood vessels.  Benign Hurthle cell tumors are not a threat at all and should not come back once they are removed.

• How Is Hurthle Cell Cancer Different from Follicular Cancer ? Hurthle cells look different than other types of thyroid cells, and they tend to occur in older patients. The median age is patients with Hurthle cell cancer is 55, about 10 years older than patients with follicular cancer. Like follicular cancer, Hurthle cell thyroid cancer infrequently spreads to lymph nodes (about 10%) but can recur locally (the cancer can come back in the neck) or spread to lung or bone.

Because younger patients with thyroid cancer tend to have a better prognosis than older patients with a very similar tumor, and because Hurthle cell cancers occur in older patients, they have the reputation of being more dangerous. However, if you control for age and other factors like size and initial extent of tumor (whether it has spread locally in the neck or elsewhere in the body), Hurthle cell tumors behave very similarly to follicular tumors. A small Hurthle cell cancer which does not have extensive invasion, especially in a younger patient (under 45), can have an excellent prognosis.

• How Is Hurthle Cell Cancer Treated?  Patients with Hurthle cell thyroid cancer, if there is more than minimal invasion, should generally undergo removal of all or nearly all of their thyroid tissue (see our article on the different types of thyroid surgery). In all areas of well-differentiated thyroid cancer, there is some disagreement about how extensive the surgery should be; however, because Hurthle cell tumors tend to occur in patients with more serious risk factors, the surgery is correspondingly more aggressive. If there are involved lymph nodes, they are removed, although this is uncommon.

Surgery may be followed with radioactive iodine. Radioactive iodine does not work as well for Hurthle cell cancer as it does for follicular cancer, because the Hurthle cells are less likely to "take up" the radioactive iodine and then be destroyed by it. However, it is well-tolerated treatment and may be helpful in some cases. Patients are then followed at regular intervals to check for recurrence, which can be dangerous in Hurthle cell cancer and needs to be watched for carefully.

About the Author: James Norman, MD, FACS, FACE, is recognized as one of world's foremost experts on parathyroid disease and the most experienced thyroid/parathyroid surgeon in the world. He is a Fellow of the American College of Surgeons (FACS) and one of only a handful of surgeons to also be a Fellow of the American College of Endocrinology (FACE). He is recognized as the inventor of minimally invasive radioguided parathyroid surgery in the mid-1990s and is credited with dramatically changing the way parathyroid surgery is performed.