This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'The treatment of choice for squamous cell anal cancer? \nSelect and explain. \nA. Laser fulgaration, B. Chemoradiotherapy, C. Abdominoperennial resection, D. Platinum-based chemotherapy', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Squamous cell anal cancer is rare but associated with Human papilloma virus infection (HPV), Anal intra-epithelial neoplasia (AIN) and immunosuppression. The current treatment of anal canal carcinoma is chemoradiotherapy (combined modality therapy). Chemotherapy include a combination of 5-FU with mitomycin C or Cisplatin. Ref: Bailey and Love Sho Practice of Surgery, 25th Edition, Page 1269; The MD Anderson Manual of Medical Oncology, 2nd Edition, Chapter 22.', 'role': 'assistant'}]