PRIMARY INTRAORAL EPITHELIOID HEMANGIOENDOTHELIOMA PRESENTING IN CHILDHOOD - REVIEW OF THE LITERATURE AND CASE-REPORT

Epithelioid hemangioendothelioma (EH) is a recently described vascular neoplasm of borderline or intermediate malignant potential. This tumo r arises from medium- to-large-sized vessels, primarily involves the s oft tissues of the extremities as well as the liver and lung, and rare ly occurs in the head and neck region. Only eight well-documented case s of intraoral EH have been reported. We present an additional pediatr ic case of EH confined to the oral cavity and review the literature re garding EH presenting as an intraoral mass. EH is characterized histop athologically as an epithelioid lesion arranged in nests, strands, and trabecular patterns with infrequent vascular spaces. Occasional eryth rocytes within intracytoplasmic lumina may be seen in tumor cells. Ult rastructural examination typically shows intracytoplasmic lumina with pseudopodial cellular membrane extensions. The cytoplasm usually conta ins intermediate filaments infrequently associated with Weibel-Palade bodies. Neoplastic cells are immunoreactive for factor VIIIR:Ag and Ul ex europaeus. Histopathologic features, which may be associated with a ggressive clinical behavior, include significant cellular atypia, one or more mitoses per 10 high-power fields, an increased proportion of s pindled cells, focal necrosis, and metaplastic bone formation. Because of the intermediate malignant potential of epithelioid hemangioendoth elioma, complete tumor resection is recommended for intraoral lesions.