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
Aim of surgery in carcinoma rectum is: March 2010 
Select and explain. 
A. Limited excision of the rectum, B. Sacrificing gastrointestinal continuity, C. Preserving the anal sphincter, D. Preserving mesorectum
C: Preserving the anal sphincter
Answer: C: Preserving the anal sphincter 
Explanation: Ans. C: Preserving the anal sphincter Principles of surgical treatment for colorectal cancer: Radical excision of the rectum together with the mesorectum and associated lymph nodes Restore gastrointestinal continuity Preserve continence by preserving the anal sphincter. A sphincter saving operation (anterior resection) is usually possible for tumours whose lower margin is two or more centimeters above the anal canal.