Multifocal intravascular papillary endothelial hyperplasia in the retroperitoneum and spine: a case report and review of the literature.

The authors present a unique case of intravascular papillary endothelial hyperplasia (IPEH) localized in the renal hilum, retroperitoneum, and spine in a patient with Wegener granulomatosis. IPEH rarely occurs in the abdomen or spine with few cases reported in the literature. No case has been reported of IPEH involving both the retroperitoneum and spine. In our case, MR imaging revealed enhancing masses in the right renal hilum and retroperitoneum as well as multiple focal enhancing lesions throughout the spine with lower thoracic ventral thecal sac compression. The diagnosis was established by resection of the renal hilum mass, and interval follow-up is deemed necessary for the remaining lesions because the long-term evolution of IPEH with conservative treatment alone is not well established.