Colorectal Cancer

Colorectal Cancer



Our surgical oncologists have specialized training and expertise in treating patients with all types of colorectal cancer – new diagnoses, advanced cases, and when recurrence occurs.

We provide services at Vancouver General Hospital and the BC Cancer Agency – offering consultation and surgery for patients from all regions of British Columbia and the Yukon.

Blausen_0246_ColorectalCancerColorectal cancer affects over 24,000 Canadians every year. The main treatment for colorectal cancer is surgery. Chemotherapy and radiation therapy are also used in some patients. Survival rates have been steadily improving since the 1980’s – due to improvements in all types of treatment, and possibly due to earlier detection.

Most colon and rectal cancers can be detected when they are small. These patients can usually be treated with laparoscopic surgery and may not require any other treatments. Some colorectal cancers are larger when diagnosed. Sometimes they have grown into other organs or body parts (for instance, the stomach, pancreas, bladder, or muscles of the belly wall). These cancers are usually treated with a combination of surgery, radiation and chemotherapy. Our surgeons are experienced in designing the best treatment combination for each patient and performing the most suitable operation – either laparoscopically or through a more traditional open incision.

If a colon or rectal cancer grows back (recurs) after it is first treated, repeat surgery is sometimes recommended. This surgery can be difficult because of scar tissue from previous surgery, the effects of previous radiation and chemotherapy treatments, and the location of the re-growing cancer. Our surgeons are experienced in performing surgery in these complex situations.

Sometimes, colorectal cancer grows outside the bowel wall and causes nodules of cancer to grow on the surfaces lining the inside of the belly (the peritoneum). In some patients it is possible to treat these nodules with a combination of surgery and chemotherapy. Our surgeons have the expertise to advise patients whether this treatment option is right for them, and to perform the surgery if recommended.

Click on the sections below to learn more about colorectal cancer and its treatment.

Over 20,000 Canadians are diagnosed with colorectal cancer each year.  A cancer can occur at any location. The most common symptoms are blood in the stool or low blood counts (anemia), decreased size of the stool, change in normal bowel habit, and weight loss. Tests such as colonoscopy and CT scan are used to diagnose colorectal cancer. These tests are also essential to help surgeons and other doctors decide on the best treatment options for each patient.
Illu_colorectal_anatomyColorectal cancer occurs in either the colon (also called the large intestine or large bowel) or the rectum. The normal colon is 4-5 feet in length and the normal rectum is 12-15 cm in length. The function of the colon and rectum are to absorb water and form solid bowel movements (stool or feces).The colon and rectum are hollow organs and their wall is made up of several layers. Colorectal cancers grow first within the inner layer (the mucosa) but then may growth through the other layers of muscle and fat. Polyps are small growths on the inner layer of the colon and rectum which, if left in place, may grow into cancers. Polyps can often be removed at the time of colonoscopy, without any need for surgery.
Surgery is the main treatment for most patients with colorectal cancer. The goal of surgery is to remove the cancer, along with the segment of colon or rectum that it came from, plus a rim of cancer-free tissue around all edges (otherwise known as a safety zone or negative margin). Surgery also aims to remove the small draining glands, called lymph nodes, that live next to the colon or rectum. After the cancer removal is completed, the bowel is either re-attached (also called anastomosis) to allow a normal flow of stool, or a stoma is created. A stoma (also called an ostomy or colostomy or ileostomy) is where the end of the bowel is brought out through the skin of the belly and the stool flows into a bag. A stoma is needed when the bowel cannot be technically or safely put back together. Some stomas are temporary and some are permanent.
Radiation is often used to treat rectal cancer – either before or after surgery. Colon cancer is not usually treated with radiation.
Chemotherapy treatments are used in some patients with colorectal cancer. After surgery for colon cancer, if the lymph nodes contain cancer cells, patients will meet with a chemotherapy doctor (medical oncologist) to discuss intravenous and/or pill forms of chemotherapy that reduce the chances of the cancer coming back (recurring). For rectal cancer, chemotherapy may be given before surgery, after surgery, or both.
After completing treatment, patients with colorectal cancer undergo regular checkups with their surgeon, chemotherapy doctor, and/or family doctor. These checkups may involve questions about any new symptoms, physical examination, blood tests, imaging such as chest xrays or CT scans, and regularly scheduled colonoscopy.