Clinicopathological Analysis of 3 Cases of Osseous Epitheliod Hemangioendothelialoma

Objective To investigate the clinicopathologic characteristics, diagnosis and differential diagnosis of osseous epitheliod hemangioendothelialoma (EHE). Methods Three cases of osseous EHE were analyzed on morphological and immunohistochemical staining features with review of the related literature. Results The age of 3 patients (2 female and 1 male) was from 14 to 36 years (mean 28.3 years). All lesions located in the lower limbs and were multifocal. The most common symptom of EHE was localized pain. Imaging examination revealed osteolytic lesion with well- or poorly-demarcated margins and variable peripheral sclerosis. Grossly, the tumors were ovoid, rubbery and brow or tan with haemorrhage. Microscopically, the tumor was composed of large polyhedral epithelioid and spindle-shaped cells. Embedded within a hyaline or myxoid matrix, both had abundant eosinophilic cytoplasms, round or elongated nuclei and prominent nucleoli. In well-differentiation parts, the tumor cells were arranged in cords or nests patterns accompanied with narrow channels or clifts. Some cells were in a diffused solid or sheet style and lack of histological profile of vascular tumor in illdifferentiation areas. And some cells contained intracytoplasmic vacuoles which represented primitive vascular lumina and they may harbor intact or fragments of red blood cells. Immunohistochemically, CD31,CD34 (or FⅧRAg) and CK were expressed in the tumor cells. Wide resection of the tumor was the preferred choice for the treatment for EHE, combined with adjuvant radiotherapy or / and chemotherapy. Conclusion Osseous EHE is a rare type of vascular tumor with malignant behavior, and the differential diagnosis includes metastasis carcinoma, epitheliod haemangioma and epitheliod angiosarcoma, etc.