Pseudomyogenic hemangioendothelioma: report of an additional case with aggressive clinical course.

: Pseudomyogenic hemangioendothelioma is a recently described vascular tumor that occurs predominantly in the distal extremities of young adults. Because of multifocal presentation, epithelioid morphology, and strong cytokeratin expression, the tumor was frequently misdiagnosed as epithelioid sarcoma. However, substantial immunohistochemical studies revealed an endothelial nature. It has been currently considered a tumor of intermediate malignancy with frequent local recurrence but low risk of distant metastasis. In this report, we describe a case of pseudomyogenic hemangioendothelioma occurring in a 22-year-old man who presented with multifocal disease in the lower extremity and developed bilateral pulmonary metastases within a short period.