Figure 2. Histopathological findings of anaplastic thyroid carcinoma. A: P01. The entire tumor shows sarcomatoid features, and no differentiated thyroid cancer component was found. B-C: P02. The tumor exhibited findings of an anaplastic thyroid carcinoma (B) with a follicular adenoma component (C). D-E: P03. Metastatic anaplastic thyroid carcinoma (D) in the lung, with a papillary thyroid carcinoma component (E). (Original magnifications: A-D: ×100; E: ×40).