Intravascular papillary endothelial hyperplasia of the cavernous sinus-A rare occurrence.

Intravascular papillary endothelial hyperplasia (IPEH) is a benign, reactive proliferation of endothelial cells within areas of thrombus. It most commonly occurs in the skin and subcutaneous tissue, with less than 40 cases reported in intracranial location. Ours is the first case report from India of IPEH in the cavernous sinus. A 45-year-old male presented with headache and decreased visual acuity. Magnetic resonance imaging (MRI) revealed a well-defined, homogeneously contrast-enhancing mass in the cavernous sinus. Postoperatively, examination of tissue showed organizing thrombus within the vessel wall along with delicate, acellular, pseudopapillary cores. The fibrin-rich connective tissue of these showed blue staining with Masson's trichrome stain. These were lined by a single layer of endothelial cells without evidence of atypia; no nuclear pleomorphism, hyperchromasia, atypical mitosis, or areas of necrosis were seen. Hence, it was diagnosed to be IPEH. Follow-up MRI revealed no residual disease and the patient is disease-free at 8 months. Recognition of this entity by pathologic examination is important to rule out angiosarcoma. Gross total resection is curative. Residual lesions have the potential for recurrence, requiring adjuvant therapy.