Anaplastic Thyroid Carcinoma Histologically Mimicking a Plasmacytoma

Diagnostics (Basel). 2020 Jan 8;10(1):29. doi: 10.3390/diagnostics10010029.


Anaplastic (undifferentiated) thyroid carcinoma (ATC) is a rare malignancy which may arise from transformation of a pre-existing differentiated carcinoma. We report the unique case where a lesion of thyroid origin presented with the histological features of mature plasma cells. Immunohistochemistry confirmed the lesion to be an anaplastic thyroid carcinoma arising from papillary thyroid carcinoma. A tumor mimicking a malignancy of a different cellular origin can lead clinicians to incorrect treatment approaches. Careful correlation with clinical details and knowledge of these unique presentations is important for reaching the correct diagnosis.

Keywords: anaplastic thyroid carcinoma; mimic; plasmacytoma.

Publication types

  • Case Reports