Medullary, anaplastic, and metastatic cancers of the thyroid.

Thyroid cancer is the most common endocrine malignancy accounting for nearly 95% of endocrine cancers according to the American Cancer Society. In 2009, more than 37,000 adults are projected to be diagnosed with thyroid cancer in the United States, and more than 1,600 people will die from the disease (www.cancer.org). A disproportionate number of these deaths will be accounted for by the rarer, but more aggressive thyroid malignancies, including medullary, anaplastic, and metastatic cancers of the thyroid. For these patients, surgical management is the only potentially curative treatment option. However, a significant amount of research is being conducted on novel therapeutic agents. This article reviews the pathology, epidemiology, clinical presentation, diagnosis, and treatment options of medullary, anaplastic, and metastatic cancers of the thyroid with an examination of emerging therapies.