Treatment

Surgery for Rectal Cancer

There are a number of different types of operation that can be carried out to treat rectal cancer, depending on how far the cancer has spread.

Some of the main techniques used are described below.

Local resection - If you have a very small, early stage rectal cancer, your surgeon may be able to remove it in an operation called a local resection (Trans anal resection).The surgeon puts an endoscope (a flexible tube with a light) in through your back passage and removes the cancer from the wall of the rectum.

Total mesenteric excision - In many cases, however, a local resection is not possible. Instead, a larger area of the rectum will need to be removed, along with a border of rectal tissue around it that is free of cancer cells and fatty tissue from around the bowel (known as the mesentery). This type of operation is known as total mesenteric excision (TME).Removing the mesentery can help ensure all the cancerous cells are removed, which can lower the risk of the cancer recurring at a later stage.Depending on exactly where in your rectum the cancer is located, one of two main TME operations may be carried out. These are outlined below.

Low anterior resection - Low anterior resection is a procedure used to treat cases where the cancer is in the upper section of your rectum.

The surgeon will make an incision in your abdomen and remove the upper section of your rectum, as well as some surrounding tissue to make sure any lymph glands containing cancer cells are also removed.

They will then attach your colon to the lowest part of your rectum or upper part of the anal canal. Sometimes, they turn the end of the colon into an internal pouch to replace the rectum. You will probably require a temporary stoma (see below) to give the joined section of bowel time to heal.
Abdominoperineal resection

Abdominoperineal resection is used to treat cases where the cancer is in the lowest section of your rectum. In this case, it will be necessary to remove the whole of your rectum and surrounding muscles to reduce the risk of the cancer re-growing in the same area.

This involves removing and closing the anus and removing its sphincter muscles too, so there is no option except to have a permanent stoma after the operation. Bowel cancer surgeons always do their best to avoid giving people permanent stomas wherever possible.

Where a section of the bowel is removed and the remaining bowel joined, the surgeon may sometimes decide to divert your stool away from the join to allow it to heal. The stool is temporarily diverted by bringing a loop of bowel out through the abdominal wall and attaching to the skin – this is called a stoma. A bag is worn over the stoma to collect the stool.

List of Routinely performed Rectal Surgeries

• removal of a polyp (polypectomy)

• A polyp is not a cancer, but cancer cells may be found within a polyp. If polyps are found during colonoscopy or sigmoidoscopy, they are surgically removed and checked for cancer cells.

• removal of tumours in the mucosa layer of the rectum (local excision or endoscopic mucosal resection)
• removal of the rectum and mesorectum (total mesorectal excision)
• removal of part of the descending colon, the sigmoid colon, all or part of the rectum and its associated mesorectum (low anterior resection)
• removal of all or part of the sigmoid colon and the entire rectum (proctectomy)
• removal of part of the sigmoid colon, rectum, anus, mesorectum and anal muscles (abdominal perineal resection)
• removal of all of the colon, rectum and pelvic organs (pelvic exenteration)
• removal of rectal cancer that has spread to the liver or lung (metastases)

Stoma surgery

Where the stoma is made from small bowel (ileum) it is called an ileostomy and where it is made from large bowel (colon) it is called a colostomy.

A specialist nurse, known as a stoma care nurse, is usually available to advise you, prior to surgery, on the best site for a stoma. The nurse will take into account factors such as your body shape and lifestyle, although this may not be possible where surgery is performed in an emergency. During the first few days post-surgery the stoma care nurse will advise on the care necessary to look after the stoma and the type of bag suitable.

Once the join in the bowel has safely healed, which can take several weeks, the stoma can be closed during further surgery. In some people, for various reasons, re-joining the bowel may not be possible or may lead to problems controlling bowel function and therefore the stoma may become permanent.

Before having surgery, the care team will advise whether it may be necessary to form an ileostomy or colostomy and the likelihood of this being temporary or permanent.

Side effects of Surgery

Colorectal cancer operations carry many of the same risks as other major operations, including the risks of bleeding, infection, developing blood clots or heart or breathing problems.

The operations all carry a number of risks specific to the procedure.

One risk is that the joined up section of bowel may not heal properly and may leak inside your abdomen. This is usually only a risk in the first few days after the operation.

Another risk is for people having rectal cancer surgery. The nerves controlling passing urine and sexual function are very close to the rectum, and sometimes an operation to remove a rectal cancer can damage these nerves.

After rectal cancer surgery most people need to go to the toilet to open their bowels more often than before, although it usually settles down within a few months of the operation.