Anaplastic Thyroid Carcinoma

Abstract

Anaplastic thyroid carcinoma (ATC) is a rare aggressive malignancy characterized by a rapidly progressive clinical course nearly always culminating in the fatal outcome. Rare reports of successful treatment and anecdotal accounts of long-term survivors of ATC contribute to the therapeutic nihilism related to ATC, although promising new treatment approaches are emerging. ATC is a rare malignancy, accounting for only 1–2% of thyroid carcinomas. In the United States, the incidence of ATC is approximately 300 cases per year, and is similar to other developed countries (Kebebew et al. Cancer;103(7):1330–5, 2005; Ain. Thyroid ;8(8):715–26, 1998). Almost all of ATC occurs in individuals above 50 years of age, and most patients present in the seventh decade of life. Slight female to male predominance has been noted, in the 1.5–2 range (Kebebew et al. Cancer;103(7):1330–5, 2005; Ain. Thyroid;8(8):715–26, 1998). The incidence of ATC has been declining in the last 20 years, perhaps reflecting more accurate classification of thyroid neoplasms, higher detection rates, and more aggressive treatment of differentiated thyroid carcinoma (DTC), which is considered to be a precursor to ATC (Ain. Thyroid;8(8):715–26, 1998; Chiacchio et al. Endocrinol;33(4):341–57, 2008).