Surgery for colorectal cancer

Most people with colorectal cancer will have surgery. The type of surgery you have depends mainly on the stage of the cancer, the size and location of the tumour and how much of the colon, rectum or both need to be removed.

Surgery may be done for different reasons. You may have surgery to:

  • completely remove the tumour and nearby lymph nodes
  • completely remove cancer that has spread to other parts of the body, such as the pelvis, liver or lung
  • remove as much of the tumour as possible (called debulking) before other treatments
  • reduce pain or ease symptoms (called palliative surgery)

The following types of surgery are used to treat colorectal cancer. You may also have other treatments before or after surgery.

Local excision

A local excision (local resection) is surgery to remove abnormal tissue, such as a polyp or tumour, along with a margin of healthy tissue around it. It is usually used to remove stage 0 tumours and some stage 1 tumours. Sometimes more surgery is needed to remove any cancer left behind or if cancer cells are found in the tissues removed with the tumour.An endoscope is usually used to do a local excision.

The following types of local excision may be done.

  • A polypectomy is surgery to remove polyps. It is done during a colonoscopy or sigmoidoscopy. Find out more about colonoscopy and sigmoidoscopy.
  • A local transanal excision is used to remove stage 0 tumours in the rectum. It can also be used for some stage 1 rectal tumours that are small and close to the anus. The surgeon uses special tools placed in the anus.
  • Transanal endoscopic microsurgery (TEM) is used to remove tumours in the rectum. The surgeon uses a special light and tiny tools passed through a proctoscope (a type of endoscope) placed in the anus. TEM can be done for stage 1 tumours that are higher in the rectum.

Bowel resection

A bowel resection is surgery to remove part of the small intestine, large intestine or both. The large intestine includes the colon, rectum and anus.

Different types of bowel resection are done to remove different parts of the intestines.

  • A right hemicolectomy is used to remove tumours in the right colon, including the cecum and ascending colon. It may be done for tumours in the appendix.
  • An extended right hemicolectomy may be done to remove tumours in the hepatic flexure (the bend in the colon near the liver) or the transverse colon.
  • A transverse colectomy may be done to remove a tumour in the middle of the transverse colon when the cancer hasn’t spread to any other parts of the colon.
  • A left hemicolectomy is used to remove tumours in the transverse colon, splenic flexure (the bend in the colon near the spleen) and the descending colon.
  • A sigmoid colectomy is used to remove tumours in the sigmoid colon.
  • A low anterior resection is used to remove tumours in the middle or upper part of the rectum.
  • A proctocolectomy with coloanal anastomosis may be done to remove tumours in the lower part of the rectum.
  • An abdominoperineal resection is used to remove tumours that are close to the anus or have grown into muscles around the anus.
  • A subtotal or total colectomy is done when there is cancer on both the right and left sides of the colon and as a way to prevent colorectal cancer for some people with familial adenomatous polyposis (FAP) or Lynch syndrome.

Find out more about a bowel resection.

Colostomy or ileostomy

A colostomy is a surgical procedure to create an opening from the colon to the outside of the body through the abdominal wall. An ileostomy creates an opening from the ileum to the outside of the body through the abdominal wall.

Depending on which part of the intestine is diseased and how healthy the rest of the intestine is, the surgeon may need to do a colostomy or ileostomy after a bowel resection.

A colostomy or ileostomy can be temporary or permanent. The doctor may do a temporary colostomy or ileostomy to allow the intestine to rest and heal after surgery. A colostomy or ileostomy will be permanent if the lower part of the rectum and anal sphincter are removed during the bowel resection.

Find out more about colostomy and ileostomy.

Lymph node dissection

A lymph node dissection is surgery to remove an area of lymph nodes. At least 12 lymph nodes near the tumour are removed during a bowel resection. They are examined to find out if cancer has spread to them.

A total mesorectal excision(TME) is a type of lymph node dissection that removes the mesorectum. The mesorectum is fat surrounding the rectum that contains lymph nodes and blood vessels. It is usually done during a bowel resection to remove cancer in the rectum. This surgery allows for a margin of tissue around the tumour to also be removed.

Find out more about a lymph node dissection.

Pelvic exenteration

A pelvic exenteration is a major surgery that removes the reproductive organs along with lymph nodes in the pelvis. For colorectal cancers, part of the colon, the rectum or both are usually removed. The bladder may also be removed.

A pelvic exenteration may be done to treat stage 4 or recurrent colorectal cancer that has spread to nearby organs.

Find out more about a pelvic exenteration.

Surgery for metastases

Surgery may be done to remove colorectal cancer that has spread (metastasized) to the liver or lungs.

Liver metastases

Surgery to remove part of the liver may be done when only one area or a few areas of cancer are found.

Radiofrequency ablation (RFA) is a treatment that may be used to treat liver metastases that can’t be removed with surgery. RFA is done with a special probe or needle inserted into the liver tumours to heat and destroy cancer cells. RFA can be given through the skin, with laparoscopy or during surgery. Find out more about radiofrequency ablation.

Find out more about liver metastases.

Lung metastases

A lung resection is surgery to remove part or all of a lung. It could be used to treat lung metastases if cancer hasn’t spread to any other organs and it is only in one area of the lung.

Find out more about lung metastases.

Side effects

Side effects can happen with any type of treatment for colorectal cancer, but everyone’s experience is different. Some people have many side effects. Other people have only a few side effects.

If you develop side effects, they can happen any time during, immediately after or a few days or weeks after surgery. Sometimes late side effects develop months or years after surgery. Most side effects will go away on their own or can be treated, but some may last a long time or become permanent.

Side effects of surgery will depend mainly on the type of surgery, the amount of bowel removed, the effects of other treatments (for example, tissue treated with radiation therapy may not heal well after surgery) and your overall health.

Side effects of surgery for colorectal cancer include:

  • pain
  • bleeding
  • blood clots
  • diarrhea or constipation
  • bowel obstruction
  • infection
  • paralyzed or inactive intestine (called paralytic ileus)
  • damage to nearby organs, such as the small intestine, bladder, ureters or spleen
  • leaking from where the 2 ends of the intestines were joined (called anastomotic leak)
  • sexual problems (for example, men may have erectile dysfunction or women may have pain during sex)
  • bladder problems, including the inability to control urination, the need to urinate often or an intense need to urinate

Tell your healthcare team if you have these side effects or others you think might be from surgery. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

Questions to ask about surgery

Find out more about surgery and side effects of surgery. To make the decisions that are right for you, ask your healthcare team questions about surgery.

Expert review and references

Medical disclaimer

The information that the Canadian Cancer Society provides does not replace your relationship with your doctor. The information is for your general use, so be sure to talk to a qualified healthcare professional before making medical decisions or if you have questions about your health.

We do our best to make sure that the information we provide is accurate and reliable but cannot guarantee that it is error-free or complete.

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