<prompt> The most common site of lymphangiosarcoma:LiverSpleenPost-mastectomy edema of armRetroperitoneum  <response>: Angiosarcoma: Rare tumour that develops as a complication of long-standing 10 years lymphoedema. Stewa and Treves described lymphangiosarcoma of the upper extremity in women with ipsilateral lymphedema after radical mastectomy. Stewa-Teres syndrome Clinical Features: Acute worsening of edema. Appearances of sub-cutaneous nodules with propensity towards hemorrhage and ulceration. Treatment: Pre-operative chemotherapy and radiotherapy followed by surgical excision radical amputation Associated with poor prognosis. Ref: Sabsiton 20th edition Pgno: 766 