Transthoracic fine-needle aspiration cytology of inflammatory pseudotumor, fibrohistiocytic type: a case report with immunohistochemical studies.

Inflammatory pseudotumor, fibrohistiocytic type, also called benign fibrous histiocytoma, is a rare reactive entity usually found incidentally on routine chest roentgenography. We present a case of inflammatory pseudotumor, fibrohistiocytic type, initially diagnosed by fine-needle aspiration (FNA) cytology in a 39-yr-old woman with a history of breast carcinoma. Cytomorphologic characteristics were confirmed by a cell block examination and immunohistochemical findings. The differential diagnoses of the fine-needle aspiration cytology of this type of inflammatory pseudotumor are discussed.