Bowel cancer, also called colorectal cancer, begins when cells that line the colon or rectum in the bowel (large intestine) change and begin to grow out of control, forming a tumour.
Bowel cancer is considered one of the most treatable cancers if detected early. However, it is sometimes not detected until at an advanced stage.
In most cases, bowel cancer is thought to develop from growths in the colon called adenomas, or polyps.
Not all polyps become cancerous, but if they do, cancer can spread through some or all of the tissue layers making up the colon and rectum, often over a period of several years.
Bowel cancer is usually slow-growing and often shows no symptoms in the early stages.
Some of the most common symptoms are bleeding from the rectum, a change in bowel habit and unexplained weight loss.
Bowel cancer is diagnosed using a number of tests, including blood tests, internal examination of the rectum, anus and colon (colonoscopy/sigmoidoscopy) and biopsy.
Imaging tests such as ultrasound, x-rays, MRI or CT scans may also be used to help with diagnosis and to learn how far the cancer may have spread.
Treatment depends on the size of the tumour, how deeply the cancer has penetrated the layers of the colon or rectum, and whether it has spread to other organs such as the liver.
If the cancer is restricted to a small area and has not yet spread, surgery to remove the cancer and surrounding tissue (including nearby lymph nodes) may be all that is required...
After treatment for bowel cancer, regular follow-up examinations and/or medical tests need to be done to look for any signs of the cancer returning, as well as to check for any late effects caused by treatment.
During and after recovery, healthy lifestyle practices are encouraged, such as maintaining a healthy weight, being physically active, not smoking, and eating well.