Colorectal Screening

Screening: when to start, what method to use

Unless you’re at higher-than-average risk for colon cancer, you should begin regular colon cancer screening at age 50.

What are the options?

• Screening colonoscopy: If you are not at high risk for colon cancer, this test is performed once every 10 years. A doctor—usually a specialist called a gastroenterologist or colorectal surgeon—will use a light and special camera on a flexible tube (colonoscope), inserted through the rectum, to examine the lining of your colon. Your doctor will give you specific instructions on how to clean out your colon to prepare for the test.  You must follow these instructions very carefully, including following the clear liquid diet, in order for the surgeon to successfully complete the examination of your colon.
• Fecal Occult Blood Test (FOBT): This test checks for hidden blood in your stool.  There are two types: guaiac, which checks for heme, the part of your blood that contain iron, and immunochemical, which uses antibodies to find hemoglobin (a blood protein). Studies have shown that FOBT, when performed every 1 to 2 years in people ages 50 to 80, can help reduce the number of deaths due to colorectal cancer by 15%- 33%.
• Barium enema (also called double contrast barium enema [DCBE] or Lower GI Series: For this test, you will be given an enema with a barium solution and air will be pumped into the colon, and then a series of x-rays will be taken. The barium and air help produce better images on the x-rays. Research shows that DCBE detects about 30%-50% of the cancers that can be found with standard colonoscopy.
• Digital Rectal Exam (DRE):  To conduct this test, your health care provider inserts a lubricated, gloved finger into your rectum and feels for any abnormalities in the lower part of the rectum. DRE may be done during a routine physical or gynecological exam.
• Sigmoidoscopy: In this test, only the lower part of the colon and the rectum are examined. The lighted instrument used is called a sigmoidoscope. If any abnormalities are seen, the sigmoidoscope can remove or biopsy those areas. Studies suggest that regular screening with sigmoidoscopy after age 50 can help reduce the number of deaths from colorectal cancer.  You will need to cleanse your colon before this procedure.
• Virtual colonoscopy:  Rather than inserting a colonoscope to see inside the colon, special x-rayequipment is used to produce pictures.  The pictures are sent to a computer that creates detailed images that show any abnormalities, such as polyps.  Though this version of a colonoscopy is less invasive, you will have to do the colon cleansing just as you would for a traditional colonoscopy.  Whether virtual colonoscopy can reduce the number of deaths from colorectal cancer is not yet known.   

Colonoscopy makes it possible to detect and remove polyps—abnormal growths that stick out from the surface—and flat lesions, or areas of abnormal cells, so they won’t develop into colon cancer. Polyps and flat lesions that are discovered during the screening colonoscopy can be removed right there and then, while you are still sedated. Colonoscopy can also detect colon cancer in the early stages, when treatment will be most effective.

Colonoscopy is the best method for directly inspecting the entire surface of the colon and rectum. If you are at a higher risk for colon cancer (personal or family history of the disease, or polyps found on previous tests), your will need to be screened more frequently, and screening may begin before age 50.  

To schedule a screening colonoscopy at Roswell Park, call 1-800-ROSWELL (1-800-767-9355).