Oral nodular endothelial hyperplasia. Report of cases and review of the literature

Intravascular papillary endothelial hyperplasia (intravascular angiomatosis) is a lesion which several authors regard as a reactive phenomenon associated with such vascular alterations as hemangiomas, hematomas, varix, thrombi or dilated vessels while others consider it a neoplasm. An extensive review of the literature and a discussion of the previously reported points of view with a report of six new oral cases (including the first such lesion associated with an oral hematoma) is presented. As it is demonstrated, this process starts as a thrombus formation with initial proliferation of endothelial cells and it ends as an endothelial nodule of main intravascular location. The importance of distinguishing this lesion from angiosarcoma is stressed and their differences discussed. We propose that the correct name for this entity is “Nodular Endothelial Hyperplasia”.