This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Lymphatic System), Subject name: Surgery
Lymphangiosarcoma occurs in? 
Select and explain. 
A. Lymphangiomas, B. Lymphomas, C. Lymphedema, D. Serous cavity tumors
C: Lymphedema
Answer: C: Lymphedema 
Explanation: ANSWER: (C) LymphedemaREF: Sabiston 18th ed chapter 69"Lymphangiosarcoma is a rare tumor that develops as a complication of long-standing (usually more than 10 years) lymphedema"Clinically, patients present with acute worsening of the edema and appearance of subcutaneous nodules that have a propensity toward hemorrhage and ulceration. The tumor can be treated, as other sarcomas, with preoperative chemotherapy and radiation followed by surgical excision, which usually takes the form of radical amputation. Overall, the tumor has a poor prognosis