Tests and Treatment
While each province/territory has its own screening recommendations, common screening tests include: Stool Tests
Fecal occult blood test (FOBT):
You collect samples from three separate bowel movements and mail them to a laboratory where the samples are analyzed for traces of blood not visible to the naked eye. If you have a positive result – which doesn’t necessarily signal cancer – you will be referred for a colonoscopy.
Fecal immunochemical test (FIT):
This newer test, which yields more accurate results than FOBT and requires only one fecal sample, is replacing FOBT in many provinces.
Recommended frequency with FOBT (either gFOBT or FIT)Adults aged 60 to 74 – every two yearsAdults aged 50 to 59 – every two years
This test uses a lighted, flexible instrument called a sigmoidoscope to examine the sigmoid colon (lower part of the colon) and rectum. Recommended frequency: every 10 years.
This is the most sensitive of all colon cancer tests. You’ll probably be under sedation while your doctor carries out this safe procedure which uses a lighted, flexible tube called an endoscope to examine the entire colon. The tube is inserted into the anus and rectum and carefully guided up through the colon. Recommended frequency: every 10 years for people at average risk of colon cancer.
The procedure usually takes 20 to 30 minutes, but can occasionally last up to an hour. You may be asked to avoid solid food for 24 to 48 hours before the examination and to take a laxative to purge the colon of any stool.
This test uses a CT scan (a type of X-ray procedure) to capture images of the colon which are generated by a computer. It takes less time than standard colonoscopy and requires no sedation, but does not allow the doctor to remove tissues for biopsy and can’t detect polyps smaller than 10 mm. Availability of the procedure varies from province to province.
The best method of screening is colonoscopy as it is most accurate and allows removal of polyps. In addition to being a more sensitive test than an air contrast barium enema in detecting abnormalities in the colon such as polyps, cancer, ulcerative colitis and Crohn’s disease, colonoscopy also allows doctors to obtain biopsies and remove polyps through a technique called snare polypectomy. This technique involves a metal loop wire being placed around a polyp and an electrical current being applied to cut the polyp off and seal the base to prevent bleeding.
Treating colon cancer
Most patients with colon cancer have resection surgery where the diseased segment is removed and the bowel on either side of the cancer is reunited. Surgical removal of colon cancer offers a potential for cure. When the growth of the tumour is small, where the cancer has not spread outside the bowel wall, the patient will do well. Larger cancers are typically treated with surgery and afterward the patient may receive chemotherapy (a special drug that kills cancer cells and may be given by mouth or injected through a vein), sometimes in combination with radiation.