Osteoclast-like giant cells admixed with other areas of sheets of pleomophic epithelioid cells are seen in this tumor.
Pleomorphic cells with large vesicular nuclei and numerous mitotic figures can be appreciated.
To the left, are several osteoclast-like multinucleated giant cells.
The osteoclastic-like cells have relatively small nuclei by comparison.
Another case with prominent osteoclast-like giant cells containing numerous nuclei.
This variant of anaplastic thyroid carcinoma is characterized by malignant single cells with admixed osteoclastic-type giant cells which are histiocytes (non-neoplastic cells). Some cases have demonstrated residual papillary carcinoma merging into the anaplastic component. Other organs have demonstrated an anaplastic carcinoma with osteoclast-like giant cells, including the breast and pancreas.
Undifferentiated (anaplastic) carcinomas of the thyroid usually affect the elderly.
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