Endocrine Pathology Online
Pathology of Anaplastic Thyroid Carcinoma
Anaplastic thyroid carcinoma, accounting for 5% to 15% of primary malignant
thyroid neoplasms, is one of the most aggressive solid tumours in humans.
Generally, it is rapidly fatal, with a mean survival of six months after diagnosis.
Multimodality treatment with surgery and/or external beam radiotherapy and
chemotherapy are of fundamental importance for local control of disease and to
The differential diagnosis of thyroid anaplastic carcinoma includes lymphoma
(some cases were previously regarded as the "small cell variant" of anaplastic
carcinoma), thyroiditis, metastases, and sarcomas.
Immunohistochemistry for cytokeratins is useful, but less so for thyroglobulin due
to non-specific uptake by some other lesions.
Anaplastic carcinomas are thought to arise by differentiation of follicular neoplasms
as evidenced by areas of poorly differentiated follicular carcinoma which may
sometimes be demonstrated by taking large numbers of blocks.
It is important to be aware of the poorly cellular variant and some extensively
necrotic and hence inflamed examples which may sometimes be mistaken for benign
Copyright © 2020 histopathology-india.net