Harvard Medical School, Boston, MA, USA.
We present the case of a 30-year-old woman who over a 10-year period has developed multiple well-differentiated angiosarcomas involving the trunk and extremities. The clinical and histologic features are characteristic of retiform hemangioendothelioma (RH), a distinctive form of low-grade angiosarcoma. This case is unique in that multiple lesions developed in different anatomic sites. We discuss the clinical and histologic characteristics, diagnosis, and prognosis of RH.