Prognostic factors of anaplastic thyroid carcinoma

Purpose. Anaplastic thyroid carcinoma (ATC) is a relatively rare but very aggressive malignancy, which usually results in death a few months after diagnosis. However, some patients survive for a long time, and the purpose of this study was to identify the prognostic factors of ATC. Methods. We retrospectively analyzed the records of 19 patients diagnosed with ATC in our institution between 1984 and 2002. Results. The median survival was 9.4 months, with a range of 0.6-76.3 months, and the 1-, 2-, and 5-year survival rates were 21%, 11%, and 5%, respectively. The mean tumor size was 5.7 cm, with a range of 3.6-10.5 cm, and complete resection was achieved in 4 patients. The prognostic factors according to univariate analysis were complete resection and small tumor size of less than 5 cm (P = 0.005 and 0.047). However, according to multivariate analysis, complete resection was the only prognostic factor for ATC (P = 0.015). No association was found between survival and acute symptoms, chemotherapy, radiation therapy, extrathyroidal invasion, distant metastasis, age, or leukocytosis. Conclusion. At present, while there is no successful treatment regimen for ATC, only patients who undergo complete resection at a very early stage have any chance of long-term survival.