Once an accurate diagnosis is made, your doctor may recommend any of several treatment options, depending on the type, size, and extent of the tumor, and your general health.
Risk Group Stratification
Doctors consider several factors before recommending a therapeutic approach for people with thyroid cancer.
Prior to selecting the appropriate treatment, our doctors use diagnostic information to determine the risk that the tumor will spread. The majority of younger patients (ages 20 to 45) have low-risk thyroid cancer — a small tumor that is confined to the thyroid. Most patients in the low-risk group are treated successfully with surgery to remove the tumor and part of the thyroid gland. Many patients, although not all, in the high-risk group are over age 45 and have extensive or aggressive cancer that has spread beyond the thyroid gland. High-risk thyroid tumors may require treatment with more extensive surgery and additional therapies, such as hormone replacement, radioactive iodine, external beam radiation, and chemotherapy.
The vast majority of patients with low-risk thyroid cancer can be cured with surgery1, and require no further treatment. Thyroidectomy — surgery to remove the tumor and part or all of the thyroid — is usually the first treatment for patients with thyroid cancer. Depending on the size and extent of the tumor, the surgeon may use one of several techniques:
In this procedure, half of the thyroid is removed along with the tumor.
- Total or Near Total Thyroidectomy
The entire thyroid, or nearly all of it, is removed.
- Minimally Invasive Surgical Techniques
In selected cases, patients with small, low-risk thyroid tumors may be candidates for minimally invasive alternatives to traditional, open surgery. When possible, the surgeon may remove all or part of the thyroid through a tiny incision in the neck. A related technique, minimally invasive video-assisted thyroidectomy (MIVAT), uses an endoscope — a narrow, lighted tube attached to a video camera - to aid in removal of the tumor through a small incision.
Removal of the lymph nodes in the neck, also called lymph node dissection, may be required if the tumor has spread or is at risk of spreading to the lymph nodes.
Thyroid Hormone Therapy
The thyroid makes thyroid hormone, which is essential for metabolism and may prevent certain thyroid cancers from returning. In addition, thyroid hormone decreases levels of thyroid-stimulating hormone (TSH), a hormone produced by the pituitary gland that promotes the growth of thyroid cancer cells. Patients who require surgery to remove their thyroid must take thyroid hormone pills every day to restore normal thyroid hormone levels. Thyroid hormone therapy also helps combat the recurrence of thyroid cancer.
Radioactive Iodine Therapy
Patients with differentiated (papillary or follicular) thyroid cancer that has spread (metastasized) beyond the thyroid may be treated with radioactive iodine following surgery. Radioactive iodine (RAI) therapy, which contains a larger dose of radiation than that found in diagnostic radioactive iodine, is absorbed by both normal thyroid and differentiated thyroid cells, destroying any thyroid tissue and cancer cells that may remain after surgery. Typically, only one or two doses of radioactive iodine — given as either a liquid or a pill - are needed to completely ablate thyroid tissue. This therapy has been shown to increase survival in some patients with metastatic papillary or follicular thyroid cancer2. RAI therapy is not effective for patients with medullary thyroid carcinoma or anaplastic thyroid carcinoma, which do not absorb iodine.
Thyroid stimulating hormone (TSH), produced by the pituitary gland, helps thyroid tissue absorb iodine. However, thyroid hormone therapy can reduce TSH levels and decrease the effectiveness of RAI therapy. In the past, patients were required to stop taking thyroid replacement pills for a period of time prior to beginning RAI therapy to increase TSH production. Discontinuing thyroid hormone therapy can temporarily result in hypothyroidism (low thyroid hormone), which causes a variety of symptoms such as fatigue, depression, weight gain, constipation, muscle aches, and reduced concentration.
For the past decade, doctors at Memorial Sloan-Kettering have offered an alternative method of raising TSH levels. Thyrogen, a synthetic form of TSH, may be given at the beginning of RAI therapy and in repeated doses, if necessary, to raise TSH levels without having to stop taking thyroid replacement medication.
Treatment Options for Recurrent Thyroid Cancer
In some patients, thyroid cancer returns following treatment with surgery and radioactive iodine therapy. Patients with recurrent thyroid cancer may receive one or more of the following treatments:
Surgery for recurrent thyroid cancer depends on the site of recurrence. The lymph nodes in the neck are the most common site of recurrence or metastasis (spread). Patients with thyroid cancer that has spread to the lymph nodes in the neck — the most common site of spread — require surgical removal of the lymph nodes in the neck. More extensive surgery may be performed if the thyroid tumor involves other vital structures in the neck. Occasionally, radioactive iodine therapy is used following surgery to treat thyroid cancer that has spread.
Radiation therapy may be used to treat patients with recurrent thyroid tumors that do not respond to or absorb radioactive iodine and are confined to one area of the body. Two types of external radiation therapy are commonly used to treat recurrent thyroid cancer:
- External-Beam Radiation Therapy
High doses of radiation are delivered from a machine outside the body. External beam radiation is usually given on an outpatient basis five days a week for five to six weeks.
- Intensity-Modulated Radiation Therapy (IMRT)
IMRT uses computer images to reveal the size and shape of the tumor. Thin, precise beams of radiation are aimed at the tumor from many angles from outside the body. IMRT targets tumors with great precision, causing less damage to healthy tissue than other types of radiation therapy.
Although chemotherapy is rarely used to treat thyroid cancer, it may be combined with external-beam radiation therapy to treat patients with metastatic disease from anaplastic thyroid carcinoma, medullary thyroid cancer, or differentiated thyroid tumors that do not respond to other therapies. Because traditional chemotherapy is relatively ineffective in the treatment of aggressive thyroid cancers, doctors at Memorial Sloan-Kettering are developing novel therapies that target the genetically defective proteins present in thyroid tumor cells. Learn more about our clinical trials.
- Bisphosphonate Therapy
Bisphosphonates, a class of drugs used to prevent bone loss, reduce the risk of fractures, and decrease pain, are sometimes prescribed to patients with thyroid cancer that has metastasized to the bones.
A. Shaha. Selective surgical management of well-differentiated thyroid cancer. Ann NY Acad Sci. 2008 Sep;1138:58-64. [PubMed Abstract]
Y. Podnos, D. Smith, L. Wagman, J. Ellenhorn. Radioactive iodine offers survival improvement in patients with follicular carcinoma of the thyroid. Surgery 2005 Dec;138(6):1072-6. [PubMed Abstract]