Colorectal Cancer Prevention and Screening
- Diet is very important for colon cancer prevention. Animal fat has been linked to an increased risk for colon cancer. A diet high in fiber and low in red meat is recommended.
- Exercise has been beneficial in reducing the risk of several cancers including colon cancer by helping maintain a normal body mass index.
- For the general population screening colonoscopy is recommended starting at the age of 50 and then every ten years if clear of disease.
- For patients with FAP (Familiar Adenomatous Poliposis) or HNPCC (hereditary nonpolyposis colorectal cancer) screening practices and preventive surgery should be discussed with a genetic counselor.
- Smoking cessation is also recommended since smoking has been linked to numerous cancers including colon.
Statistically colonoscopy is associated with a 70% reduction in the risk of late stage colon cancer. Sigmoidoscopy is associated with a reduction in risk of developing left sided colon cancer. Both procedures are associated with a reduction in mortality from colon cancer.
For the general population colorectal cancer screening starts at the age of 50 for both sexes. Fecal occult blood test is recommended yearly.
Flexible sigmoidoscopy is done at age 50 and if clear every three years. The procedure is done in the office therefore is convenient. The drawback I see is that it visualizes only the left side of the colon omitting the right side with the potential of missing up to 35% of lesions. Screening colonoscopy starts at age 50 and if clear is repeated every ten years. In my opinion this is the best screening method because if polyps are visualized, removal can occur during the procedure, and if suspicious lesions are visualized, a biopsy can be performed in the same setting.
Virtual colonoscopy is attractive to many individuals who want to avoid the scope. The biggest drawback is that if polyps or lesions are visualized, the test needs to be followed by a regular colonoscopy in order to remove the polyps or perform a biopsy.
Again for patients at high risk like FAP, HNPCC, or inflammatory bowel disease the screening is much more frequent and starts at a much younger age.