Rare tumors of the thyroid gland.

Although the vast majority of thyroid cancers are well-differentiated and carry an excellent prognosis, several rare tumors occasionally involve the thyroid gland and require unique treatment paradigms. Anaplastic carcinoma of the thyroid is an extremely aggressive neoplasm that is generally best managed with surgery followed by a multimodality regimen of radiotherapy and chemotherapy. Squamous cell carcinoma of the thyroid often mimics the clinical course of anaplastic carcinoma and is best treated with aggressive surgery followed by postoperative radiotherapy. Treatment and prognosis of lymphoma of the thyroid varies depending upon the specific pathological subtype, with combination chemotherapy and radiation therapy used primarily. Sarcomas of the thyroid are primarily managed with surgery, although radiation and chemotherapy are indicated in some cases.