An unusual presentation of Stewart-Treves syndrome on the lower extremity

INTRODUCTION Cutaneous angiosarcoma is a rare and aggressive malignant tumor derived from endothelial cells, which can develop de novo, in irradiated skin, or in areas of chronic lymphedema. Stewart-Treves syndrome describes the association of cutaneous angiosarcoma arising in the setting of lymphedema. This syndrome was first reported in 1948 by Drs Fred Stewart and Norman Treves, who noted 6 cases of lymphangiosarcoma that developed several years after a Halstead radical mastectomy. Currently there are few reports in the literature of Stewart-Treves syndrome occurring after primary or secondary causes of chronic lymphedema not attributable to malignancy. Our case is an extremely rare subtype of angiosarcoma arising in a lymphedematous lower limb with no prior malignancy or radiation history.