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': 'Which type of malignancy is found in anorectal fistulaa) Sq. cell Cab) Transitional Cell Cac) Adeno Cad) Columnar Ca \nSelect and explain. \nA. a, B. bc, C. ac, D. b', 'role': 'user'}, {'content': 'Answer: C \nExplanation: • MC type of carcinoma to arise in fistula-in-ano: Colloid carcinoma\xa0(44%) > Squamous cell carcinoma (34%) > Adenocarcinoma (22%)\n• Clue to early diagnosis is the appearance of mucin globules\xa0in Fistulotomy or fistulectomy specimens', 'role': 'assistant'}]