intravascular papillary endothelial hyperplasia intravascular papillary endothelial hyperplasia intravascular papillary endothelial hyperplasia is a rare, benign tumor. it may mimic an angiosarcoma, with lesions that are red or purplish 5-mm to 5-cm papules and deep nodules on the head, neck, or upper extremities.: 592 intravascular papillary endothelial hyperplasiaother namesmasson's hemangio-endotheliome vegetant intravasculaire, masson's lesion, masson's pseudoangiosarcoma, masson's tumor, and papillary endothelial hyperplasiaspecialtyoncology, rheumatology pathology histopathology images