Advanced Thyroid Cancer

Determining the Type of Advanced Thyroid Cancer

Only after a pathologist analyzes some cells or actual pieces of tissue from the lesion will your doctor be able to tell you if you have cancer. There are a few different types of thyroid cancers, as well as a few subtypes.

A thyroid cancer can be considered advanced if:

  • The type of thyroid cancer is known to behave aggressively (i.e., poorly differentiated thyroid cancer, medullary thyroid cancer).
  • The cancer in the thyroid is behaving aggressively (i.e., has spread outside the thyroid gland or paralyzed a vocal cord).
  • The cancer has spread to the neck or other parts of the body (metastatic thyroid cancer).

One of the simplest ways to separate different types of thyroid cancers is to break them into well-differentiated thyroid cancers (these resemble normal thyroid cells) and poorly differentiated thyroid cancers (these cells have grown in a way that they only partly resemble thyroid cells). Well-differentiated thyroid cancers are by far the most common types of thyroid cancers seen in the U.S. Well-differentiated thyroid cancers include most papillary carcinomas and most follicular carcinomas.

Types and subtypes of thyroid cancer include:

  • Papillary thyroid cancer: This is the most common type of thyroid cancer. The cells usually resemble thyroid cells. There are several subtypes, including:
    • Classical
    • Follicular variant
    • Tall cell variant
  • Follicular thyroid cancer: This is another (usually) well-differentiated thyroid cancer. The diagnosis of a follicular thyroid carcinoma can really only be made after the gland (or at least half of the gland) is analyzed under a microscope. The diagnosis is made when follicular cells in the tumor are seen in the capsule of the tumor or within blood vessels. If this is not seen, then you have a benign follicular tumor. One more aggressive subtype of follicular carcinoma is Hurthle cell carcinoma.
  • Medullary thyroid cancer: This type of cancer comes not from follicular cells in the thyroid gland but from cells between the follicles called C-cells. These cells are like neuro-endocrine cells and secrete calcitonin into the body. Calcitonin helps with calcium regulation in your body. When calcitonin levels are very high, this is a sign that you have medullary thyroid carcinoma. This can be very closely associated with genetics (family history) and other hormone problems.
  • Anaplastic (undifferentiated) thyroid cancer: This is a very aggressive thyroid cancer that is poorly differentiated. It is generally considered incurable. If it is caught early and is completely within the thyroid gland, surgical removal might be an option. Otherwise, patients are usually entered into clinical trials, and some combination of chemotherapy with or without radiation is attempted.
  • Other: In very rare cases, spread of cancer from other sites can spread into the thyroid gland, or you can get a lymphoma in the thyroid gland or a squamous cell carcinoma of the thyroid.

1 SEER Fast Facts. Accessed February 2013.

2 Hundahl SA, Fleming ID, Fremgen AM, et al.: A National Cancer Data Base report on 53,856 cases of thyroid carcinoma treated in the U.S., 1985-1995. Cancer. 1998;83:2638-2648.

3 Salerno P, De Falco V, Tamburrino A, Nappi TC, Vecchio G, Schweppe RE, Bollag G, Santoro M, Salvatore G. Cytostatic activity of adenosine triphosphate-competitive kinase inhibitors in BRAF mutant thyroid carcinoma cells. J Clin Endocrinol Metab. 2010;95(1):450-455.

4 Cooper, D.S., G. M. Doherty, et al. (2009). “Revised American Thyroid Association Management Guidelines for Patients with Thyroid Nodules and Differentiated Thyroid Cancer: the American Thyroid Association (ATA) Guidelines Taskforce on Thyroid Nodules and Differentiated Thyroid Cancer.” Thyroid 19(11): 1167-1214.

5 Ries LAG, Young JL, Keel GE, Eisner MP, Lin YD, Horner M-J (editors). SEER Survival Monograph: Cancer Survival Among Adults: U.S. SEER Program, 1988-2001, Patient and Tumor Characteristics. National Cancer Institute, SEER Program, NIH Pub. No. 07-6215, Bethesda, MD, 2007.