Primary Peritoneal Epithelioid Hemangioendothelioma

Abstract

Epithelioid hemangioendothelioma is an uncommon malignant vascular tumor of intermediate grade that occurs in a variety of organs and soft tissues. Diagnosis of epithelioid hemangioendothelioma is often complicated by the rarity of the tumor, and because the tumor shares many morphologic features with other peritoneal neoplasms. This report presents 3 cases of epithelioid hemangioendotheliomas arising as primary tumors of the peritoneum and reviews 7 previously reported cases to establish the demographic, clinical, morphologic, immunohistochemical, and ultrastructural features of this neoplasm. These cases demonstrate that the light microscopic features are very similar to epithelioid hemangioendothelioma arising at more conventional sites, such as the liver, that immunohistochemical analysis provides a reliable approach for confirming or establishing the diagnosis, and that at least one endothelial marker (either CD31, CD34, or factor VIII) should be positive for a definitive diagnosis. This series identifies the characteristics of peritoneal epithelioid hemangioendothelioma that can be reliably used for diagnosis.

Epithelioid Haemangioendothelioma of the Mesentery

“…The principal symptoms of the patient are abdominal pain and right iliac fossa swelling that kept on increasing in size, these symptoms are similar to those reported by Posligua et al [6] and Hamirani et al [13] in their studies on primary peritoneal epithelioid haemangioendothelioma.…”

“…The following vascular markers of CD31, CD34, S-100, Vimentin and factor VIII-antigen, as well as thrombomodulin, differentiate EHE from the other tumor types [6]. Although Immunohistochemistry is essential in characterizing the tumour and in differential diagnosis, but Zarifa and Kemal [15] did not find immunohistochemistry that useful due non-specificity of these marker as some are also expressed by benign vascular tumours.…”

“…Immunohistochemistry is an essential adjunct for differentiation EHE from morphologic pretenders, including carcinoma, epithelioid leiomyosarcoma, and malignant gastrointestinal stromal tumor with epithelioid features [6]. The following vascular markers of CD31, CD34, S-100, Vimentin and factor VIII-antigen, as well as thrombomodulin, differentiate EHE from the other tumor types [6].…”

“…We demonstrate that the light microscopic features are very similar to EHE arising at more conventional sites such as the liver, that immunohistochemical analysis provides a reliable approach for confirming or establishing the diagnosis, and that at least 1 endothelial marker (either CD31, CD34, or factor VIII) should be positive for a definitive diagnosis [6].…”

“…Overall, EH has an equal sex distribution, although cases presenting in the lungs and liver are more frequent in women [6]. There is virtually no site which is immune to the occurrence of an EH [7][8][9][10].…”