Lymphangiosarcoma (LAS) is an aggressive, malignant vascular tumor following long-lasting chronic lymphedema. Patients with LAS demonstrate a history of breast cancer treated by radical mastectomy in the majority of patients. In the 1960s the incidence of LAS in patients with a 5-year survival after radical mastectomy varied from 0.07 to 0.45%. Today, due to changes in the operative techniques of breast cancer, less chronic lymphedema is seen with only a scant number of LAS patients. The etiology of this enigmatic tumor is not yet completely understood. Histologically, LAS arises from vascular endotheliocytes, and all vascular sarcomas originating in the setting of a chronic lymphedema are categorized as LAS. There is no standard treatment of LAS. The treatment options include radical ablative surgery, radiation therapy, and chemotherapy. The prognosis of LAS is poor; long-term survival is the exception. Only early recognition and radical surgery offer a chance of cure.