Prognostic factors and treatment outcomes of 100 cases of anaplastic thyroid carcinoma

Abstract

Background: Anaplastic thyroid carcinoma (ATC) is a malignancy with one of the highest fatality rates. Here we report a retrospective study of the treatment and other factors associated with its outcomes.

Materials and methods: The medical records of 100 patients diagnosed with ATC at Ito Hospital between 1993 and 2009 were reviewed and pertinent information was extracted and analyzed.

Results: There were 80 women and 20 men, and their median age at diagnosis was 68 years (range, 41-90 years). Thirteen patients had a history of well-differentiated thyroid carcinoma. Six patients had a small ATC focus within a differentiated carcinoma. All cases were retrospectively staged according to the Union for International Cancer Control classification system, and the results were stage IVA in 11 cases, stage IVB in 31 cases, and stage IVC in 58 cases. Seventy patients underwent surgical treatment, and complete resection was performed in 24 of them. Seventy-eight patients received radiotherapy, and 58 of them received a total dose of ≥40 Gy. Twenty-seven patients received chemotherapy. Only 15 patients received multimodal therapy (surgery, radiotherapy, and chemotherapy). The 1-year survival rates according to stage were as follows: stage IVA, 72.7%; stage IVB, 24.8%; and stage IVC, 8.2%. Multivariate analysis identified age ≥70 years, white blood cell ≥10,000 mm(3), extrathyroidal invasion, and distant metastasis at the time of diagnosis as prognostic factors. Survival after complete resection was significantly better than after incomplete resection or no resection. The results also suggested that radiation doses of ≥40 Gy were associated with significantly longer survival.

Conclusion: Although the prognosis of most patients with ATC continues to be poor, surgery, radiotherapy, and a combination of both improved the survival of patients with ATC.