Fine Needle Aspiration Cytology of Pulmonary Epithelioid Hemangioendothelioma with Prominent Hyaline Degeneration - A Case Report

Pulmonary epithelioid hemangioendothelioma (PEH) is a rare vascular tumor of low to intermediate malignant potential, and PEH can mimic other more common tumor entities pathologically as well as clinically. Compared to its well-recognized histological features, its cytological findings have been reported rarely to be plasmacytoid or epithelioid cells with abundant dense or finely granular cytoplasm, cytoplasmic vacuoles, round nuclei and prominent nucleoli. We report here on the fine needle aspiration cytologic findings of a 38-year-old woman with EH of the lung, that showed in addition to its classical cytomorphology, a somewhat peculiar cytologic finding such as big twig-like rosettoid structures with prominent hyalinized stroma. This tumor was histologically and immunohistochemically proven to be PEH by primary antibodies for CD31, CD34 and vimentin. We emphasize that the accuracy of making a cytologic diagnosis of this rare tumor can be increased by recognizing the peculiar cytologic finding that we report on here.