Rectal surgery

The simplest form of surgery is local excision of the tumor during colonoscopy.

However, this is only possible if the rectal cancer is at very early stages, with the tumor still confined in a polyp. In these cases, removal of the polyp during colonoscopy might be sufficient to treat the disease.

This is done using specialized instruments, inserted through the hollow space inside the colonoscope, to cut and remove the polyp from its stem. The process is called polypectomy.

When cancer is already advanced, surgery to remove rectal tumors tends to be more complex than for those in the colon, because of the need to work within the pelvic bone. It is here that the nerves controlling sexual and urinary functions are located, so extra care must be taken to avoid damage. The surgery requires some experience and expertise.

Furthermore, the rectum is also critical for our bowel function.

The impact of a  proctectomy  (surgery that removes all or part of the rectum) depends largely on the location of the tumor, its size, and the tumor foci (number of tumors). If the surgery is performed in the middle / upper segment of the rectum, the sphincter can be saved, avoiding a permanent colostomy (a surgical procedure where one end of the bowel, through an opening in the abdominal wall, excretes feces to an external bag).

To save function as much as possible, treatment for rectal cancer often starts with chemotherapy or radiotherapy to shrink the tumor before surgery and help its full removal. 

Even if the cancer is already advanced, and has spread beyond the rectum (e.g., to the lymph nodes), chemical or radiotherapy before surgery can still help by destroying any micrometastases (new tumors too small to be detected) reducing the risk of disease recurrence.