Local resection surgery
If an anal, rectal or colon cancer is small and has not spread, the surgeon may perform a local resection. For this, the surgeon removes the tumor along with some surrounding tissue. Usually, with this type of surgery, the sphincter is not damaged. This means that the patient will still be able to pass stool in the normal way.
The most common surgery for colon cancer, called a colectomy, removes the part of the colon that contains the cancer. Surgery for rectal cancer is called a transanal resection, low anterior resection, proctectomy, or an abdominoperineal resection, depending on the location and extent of the surgery.