Soft tissue angiosarcoma of the breast in a patient with Klippel-Trenaunay-Weber syndrome.

Angiosarcomas are neoplasms of blood or lymphatic vessels with aggressive behavior. We report the coexistence of this malignancy within soft tissue of the breast in a 49-year-old woman who was diagnosed with Klippel-Trenaunay-Weber syndrome (KTW-S) during childhood. The patient has no previous history of radiation therapy on the chest and does not have any known risk factor for developing angiosarcoma, except for her congenital disease. To the best of our knowledge, the association between soft tissue angiosarcoma of the breast and KTW-S has never been previously reported.