Colon Cancer Screening and Red Poop

You should monitor the state of your poop because it can indicate early (or late) warning signs of serious digestive tract problems. Black poop or tarry stools may be due to colon cancer. For more information, please see the colon cancer screening and fecal occult blood test articles.

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Early detection is vital. There are a number of tests that might be appropriate. We'll explain each test and when it is needed:

• Fecal occult blood test (FOBT)
• Sigmoidoscopy
• Regular, or standard, colonoscopy
• Virtual colonoscopy
• Double contrast barium enema (DCBE)
• Digital rectal exam (DRE)

Colorectal cancer screening is used to detect

• Cancer
• Polyps
• Nonpolypoid lesions

Finding and removing polyps or other areas of abnormal cell growth may be one of the most effective ways to prevent colorectal cancer development. Colorectal cancer is generally more treatable when it is found early, before it has had a chance to spread. Watch your poop for signs of bleeding (Hematochezia) that can be a sign of colon cancer.

Different Tests For Colon Cancer

One or more of the following tests are often prescribed:

• Fecal occult blood test (FOBT) - checks for hidden blood in fecal material (stool). Currently, two types of FOBT are available. One type, called guaiac FOBT, uses the chemical guaiac to detect heme in stool. Heme is the iron-containing component of the blood protein hemoglobin. The other type of FOBT, called immunochemical FOBT, uses antibodies to detect human hemoglobin protein in stool. 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 to 33 percent.
• Sigmoidoscopy - the rectum and lower colon are examined using a lighted instrument called a sigmoidoscope. During sigmoidoscopy, precancerous and cancerous growths in the rectum and lower colon can be found and either removed or biopsied. Studies suggest that regular screening with sigmoidoscopy after age 50 can help reduce the number of deaths from colorectal cancer.
• Colonoscopy - the rectum and entire colon are examined using a lighted instrument called a colonoscope. During colonoscopy, precancerous and cancerous growths throughout the colon can be found and either removed or biopsied, including growths in the upper part of the colon, where they would be missed by sigmoidoscopy. However, it is not yet known for certain whether colonoscopy can help reduce the number of deaths from colorectal cancer. A thorough cleansing of the colon is necessary before this test, and most patients receive some form of sedation.
• Virtual colonoscopy (computerized tomographic colonography) - special x-ray equipment is used to produce pictures of the colon and rectum. A computer then assembles these pictures into detailed images that can show polyps and other abnormalities. Because it is less invasive than standard colonoscopy and sedation is not needed, virtual colonoscopy may cause less discomfort and take less time to perform. As with standard colonoscopy, a thorough cleansing of the colon is necessary before this test.
• Double contrast barium enema (DCBE) - a series of x-rays of the entire colon and rectum are taken after the patient is given an enema with a barium solution and air is introduced into the colon. The barium and air help to outline the colon and rectum on the x-rays. Research shows that DCBE may miss small polyps. It detects about 30 to 50 percent of the cancers that can be found with standard colonoscopy.
• Digital rectal exam (DRE) - a health care provider inserts a lubricated, gloved finger into the rectum to feel for abnormal areas. DRE allows examination of only the lower part of the rectum. It is often performed as part of a routine physical examination.