Oral intravascular papillary endothelial hyperplasia: Case report and review of literature

Intravascular papillary endothelial hyperplasia (IPEH) is an uncommon benign vascular lesion that comprises a reactive proliferation of endothelial cells arising from a consolidating thrombus. Oral presentations of IPEH are relatively rare, and when they do occur the most common affected site is the lower lip; in addition, IPEH can be mistaken for an angiosarcoma. This present report aims to describe an IPEH affecting the buccal mucosa, besides exposing 20 other cases of IPEH that were published over the past 40 years and that occurred within this same oral location. A literature review of those lesions along all other cases of oral IPEH was performed and took into consideration several aspects of the lesions, including their immunohistochemical profiles. The present case was diagnosed as IPEH due to characteristic histopathological findings and immunohistochemical reactions for CD34 and vimentin, which revealed strong positivity in the lining endothelial cells and confirmed the vascular origin of the lesion. Additionally, a positive reaction for laminin was observed in the basal membrane of the vessel walls. Low positivity for Ki-67 and an unexpected though interesting immunopositivity for GLUT-1 was observed. We emphasize that knowing the clinical characteristics, the specific histological arrangement and the immunophenotype of IPEH is extremely important for establishing the correct diagnosis and treatment among similar lesions.