Hemangioendothelioma. Cytologic appearances in two cases presenting with multiple soft tissue and bone lesions.

Two cases of hemangioendothelioma were detected by fine needle aspiration cytology in two women presenting with multiple soft tissue and bone lesions. The aspirates were hemorrhagic, and the smears showed mostly dissociated and predominantly monomorphic tumor cells. Focal rosettelike clustering of tumor cells was also present. A prominent cytologic feature of these two cases of hemangioendothelioma was the close association of tumor cells with endothelium-lined vascular structures, a pattern that can be seen in other sarcomas and sometimes in malignant epithelial tumors.