Anaplastic thyroid cancer: a review of epidemiology, pathogenesis, and treatment.

Anaplastic thyroid cancer (ATC) is an uncommon malignancy of the thyroid. Only 1-2% of thyroid cancers are anaplastic, but the disease contributes to 14-50% of the mortality with a median survival of 3 to 5 months. Most patients diagnosed with this disease are 65 years of age or older. The incidence of anaplastic thyroid cancer is decreasing worldwide. Most patients present with a rapidly growing neck mass, dysphagia, or voice change. We performed a comprehensive literature search using PubMed focusing on the treatment of anaplastic thyroid cancer including historical review of treatment and outcomes and investigations of new agents and approaches. A total of sixteen chart review and retrospective studies and eleven prospective studies and/or clinical trials were reviewed. The current standard therapeutic approach is to consider the disease as systemic at time of diagnosis and pursue combined modality therapy incorporating cytoreductive surgical resection where feasible and/or chemoradiation either concurrently or sequentially. Doxorubicin is the most commonly used agent, with a response rate of 22%. Several new agents are currently under investigation. Referral of patients for participation in clinical trials is needed.