Total metabolic regression after everolimus in an adult patient with pseudomyogenic hemangioendothelioma

Pseudomyogenic hemangioendothelioma (PHE) is a rare vascular tumor harboring the pathognomonic SERPINE1-FOSB fusion. Most patients are treated primarily with surgical resection, but some patients require systemic therapy due to multiple metastases at initial presentation or multifocal recurrence after definitive resection. The most optimal treatment strategy for the disease has yet to be clearly defined; however, mammalian target of rapamycin inhibitors show promise-given–reported anecdotal responses from case reports of pediatric patients. We present an adult patient with multifocal PHE who was successfully treated with everolimus with a significant clinical response.