Colon Cancer Screening
Typically, colon cancer screening helps in the detection of early signs of cancer in the intestine. With regular screening, it is possible to detect problems in the form of polyps that can otherwise become cancerous if left untreated. So timely screening helps reduce the risk of death from colon cancer. Identification of pre-cancerous growths helps in their treatment before they become malignant.
Before the examination day, the patient is required to avoid solid food and use laxatives to empty the colon. A cancer of the colon, colorectal cancer shows no initial signs when it first starts to develop. Then with the progress of the cancer, common symptoms start to show up, such as alteration in bowel habit, anemia, bleeding from rectum, and diarrhea.
Most precancerous polyps result in colorectal cancers. Polyps are a form of skin growths in the lining of the intestine. They may become visible when the doctor examines the bowel during endoscopy – either through sigmoidoscopy or colonoscopy. Some forms of polyps, such as adenomatous polyps, are known to become cancerous.
Colon cancer screening tests work by detecting polyps or early stage cancers followed by removal of the abnormality. Regular screening for and removal of polyps reduces your risk of developing colorectal cancer – by up to 90 percent with colonoscopy. Early detection of cancers that are already present in the colon increases the chance of successful treatment and decreases the chance of dying as a result of the cancer.
Risk Factors of Colon Cancer
- Family history of colorectal cancer
- Colorectal polyps
- Increasing age, especially beyond 50 years
- Lifestyle factors
- Inflammatory bowel disease
Often little amount of bleeding can result from small cancers or polyps in the colon. Since this bleeding cannot be seen with naked eye, stool test is performed to check for traces of blood in the stool.
Here are the common stool tests done to detect cancer of the colon:
- Fecal Immunochemical Test
- Fecal Occult Blood Test – detects traces of blood in the stool
- Stool DNA Test
The minimally invasive test is done to view just the lower part or one-third of the colon, so there is a high risk that the test could miss some cancers located higher in the large intestine. It is commonly done to detect polyps in the lower colon and rectum.
This test gives a better picture of the large intestine, as the entire colon can be viewed, unlike signoidoscopy where you can view the lower colon alone. The doctor prescribes medicine to promote relaxation. Double-contrast barium enema is a special x-ray that looks at the large intestine, colon and rectum.
After you cross 50 years of age, it is important to have a colon cancer screening test done. Anyone with colon cancer risk should get fecal occult blood test every year and colonoscopy done every 10 years. Virtual colonoscopy test or computed tomography colonography uses a CT scanner that captures two- and three-dimensional images of the entire bowel to determine the presence of polyps or cancers.