[The anaplastic thyroid carcinoma research consortium of Japan].

Anaplastic thyroid carcinoma (ATC) is one of the most lethal neoplasia in humans, with a disease-specific mortality rate approaching 100%. ATC is uncommon and represents only 1-2% of all thyroid carcinomas. The aggressive nature and rarity of this disease make it difficult to improve the quality of evidence on it. To date, most existing knowledge of ATC is derived from single-institution studies with limited cohorts and short-term follow-up. To obtain further insights into this "orphan disease," we established the ATC Research Consortium of Japan (ATCCJ) in January 2009 as a multicenter registry that accumulates, analyzes, and reviews all information on ATC available in the country. As of July 2011, the ATCCJ database included 721 cases of ATC from 38 institutions. Using the database, the members of the ATCCJ have performed several retrospective studies, covering prognostic factors, therapeutic strategies, and pathologic features of ATC. Moreover, prospective trials are being planned as multicenter collaborations to determine the most beneficial treatment, with the ultimate purpose of improving the survival rate of patients with ATC.