Hemangiopericytoma: A light microscopic and ultrastructural study

Abstract

An ultrastructural study of three cases of hemangiopericytoma showed cells partially or completely enveloped by well-formed basement membrane and basement membrane-like material. The cells exhibited prominent cytoplasmic filaments, some showing dense body formation, interdigitating cytoplasmic processes, and pinocytotic vesicles. A review of the literature revealed only 19 other cases of hemangiopericytoma studied by electron microscopy, and these included seven cases of meningeal origin ("angioblastic meningioma"). The most consistent feature seen in all but two cases was the presence of a basal lamina or basal lamina-like material either partially or completely surrounding tumor cells and separating endothelial cells from pericytes. The light microscopic diagnosis of hemangiopericytoma is difficult, and there is a tendency to append the diagnosis to a variety of other tumors with a prominent vascular pattern in which other specific diagnoses are not immediately evident. The presence, ultrastructurally, of well-developed basement membrane, myogenic type filaments, and pinocytotic vesicles in a tumor with light microscopic features suggestive of hemangiopericytoma would consolidate the diagnosis and usually eliminate diagnostic uncertainty.

Hemangiopericytoma of the Nasal Cavity: A Review of 15 Cases over a 40-Year Period

“…2 12 Eichorn et al and Batsakis et al showed no distinction between the ultrastructural findings of nasal hemangiopericytomas and those of other sites. The tumor must be differentiated from other vascular tumors, fibrous histiocytomas, smooth muscle tumors, and soft tissue sarcomas by subtle histologic features, Reticulin stains are helpful in defining the vascular spaces; in hemangiopericytomas, this stain will display the perivascular growth of pericytes in contrast to the intravascular growth of hemangioendothelioma cells.…”

Post‐operative stereotactic radiotherapy for the treatment of intracranial haemangiopericytoma: ‘A Study of Dose and Outcome’

“…9,10 According to findings from several studies, radiotherapy is an effective treatment for intracranial haemangiopericytoma. These tumours comprise <2.5% of meningeal tumours and <1% of all intracranial tumours.…”

Sinonasal Glomangiopericytoma

“…This lesion was thought to fall in the spectrum between glomus tumors and capillary hemangioma, and hence the term hemangiopericytoma was chosen. 10 Compagno and Hyams 3 described these lesions as intranasal hemangiopericytoma tumors. It is now widely accepted as a type of so-called sinonasal hemangiopericytoma, now known as glomangiopericytoma, which is different from the traditional soft-tissue hemangiopericytoma rep-resenting as a separate lesion.…”