Intracranial papillary endothelial hyperplasia: occurrence of a case after surgery and radiosurgery

Papillary endothelial hyperplasia (PEH) is considered a form of endothelial proliferation rather than a true neoplasm and is usually located in the skin or subcutis. We report a case of intracranial PEH that occurred after surgery for glioma and subsequent radiosurgery. CT and MR revealed an enhancing extra-axial mass located left posterolateral to the brainstem. Intracranial PEH is rare; to our knowledge, development of an intracranial PEH after surgery and radiosurgery has not been previously reported.