Benign lymphangioendothelioma of the thigh simulating a low-grade angiosarcoma.

Benign lymphangioendothelioma (BL) is a rare vascular neoplasm that can histopathologically mimic a low-grade angiosarcoma or the patch stage of Kaposi sarcoma. We report on the case of a 49-year-old man with a benign lymphangioendothelioma on the right thigh that evolved on a vascular birthmark after a trauma. Because of constant pain and the slow but progressive growth of the lesion, we decided to excise the tumor. Three stages of surgery were needed to obtain negative margins. We review the reports of BL to date, with special attention to those that developed after trauma and those that had a preexistent vascular lesion, and expound on the histopathologic differential diagnosis with low-grade angiosarcoma.