Colorectal cancer

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Treatments for stage 1 rectal cancer

The following are treatment options for stage 1 rectal cancer. Your healthcare team will suggest treatments based on your needs and work with you to develop a treatment plan.


Surgery is the main treatment for stage 1 rectal cancer. A bowel resection is usually the type of surgery done. Depending on the location of the tumour, the surgeon may do a low anterior resection or abdominoperineal resection with total mesorectal excision. If the surgeon does a low anterior resection, the remaining 2 ends of the colon are joined together (called anastomosis).

In some cases, the surgeon may use local transanal excision or transanal endoscopic microsurgery (TEM) to remove a small, low-grade, stage 1 tumour if you can’t have major surgery. These surgeries are only an option if the surgeon can remove enough tissue around the tumour to have clear surgical margins (which means there are no cancer cells in the tissue removed along with the tumour). Bowel resection is preferred over these surgeries because they have a greater risk of recurrence, and it will be harder to completely remove the cancer if it comes back.

Depending on the type of surgery done, the surgeon may need to do a temporary or permanent colostomy or ileostomy.


Chemoradiation combines chemotherapy with radiation therapy. Chemotherapy is given during the same time period as radiation therapy. Some types of chemotherapy make radiation therapy more effective.

You may be offered chemoradiation before surgery for stage 1 rectal cancer that is close to the anus. Chemoradiation may help shrink the tumour so the surgeon doesn’t need to remove the anal sphincter. If the anal sphincter isn’t removed, you don’t need a permanent colostomy or ileostomy.

Chemoradiation is usually given as 25–30 treatments of radiation therapy (called a long course of radiation) and chemotherapy with 5-fluorouracil (Adrucil, 5-FU) or capecitabine (Xeloda) given for 5–6 weeks.

Radiation therapy

Radiation therapy alone may be given after local transanal excision or TEM to remove stage 1 rectal cancer.

Clinical trials

You may be asked if you want to join a clinical trial for rectal cancer. Find out more about clinical trials.


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