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CLA: STOOL OCCULT BLOOD
COLON AND RECTUM
The large intestine or colon is the last part of the human digestive tract and is 5-6 feet long. The last 8 inches or so is called the rectum. After food has been digested in the stomach and its nutrients absorbed in the small intestine, it moves to the colon. The colon is very effective in removing water from the material inside, now called fecal material or stool, and stores the stool for convenient evacuation. At any adult age, but especially at around age 50, the incidence of cancer of the colon and rectum begins to rise, becoming the second most common cause of cancer death in the US. Those individuals having a higher-than-usual colorectal cancer risk are those with a family history of cancer of the colon, rectum, breast or ovaries, those with an inflammatory disease of the colon (for example, ulcerative colitis or Crohn’s disease), those with colon polyps (benign cauliflower-like growths), or those in families with a hereditary form of the disease.
Cancer of the colon, unlike many cancers, can be diagnosed early by several different tests/X-rays/or examinations and is curable at an early stage. Its symptoms depend upon where it presents in the colon or rectum. If in the first part of the colon (near the small intestine), the person will have early anemia, possibly dark blood in the stool and may have crampy abdominal pain. If the cancer is in the remainder of the colon, the person will more likely have bright red blood in the stool and symptoms of blockage, such as smaller diameter of the stool and constipation.
TEST FOR OCCULT (HIDDEN BLOOD IN THE STOOL
After you have collected a stool sample as directed and brought it to the lab, a chemical test for the presence of blood is performed. Because a diet of meat can cause a “false-positive” test (the test confuses chemically similar materials in the meat for blood), you should not have eaten meat for 3 days prior to collecting the stool sample. If the instructions have been followed and blood is identified in the stool sample, you should arrange to review this result with a community physician of your choice. But remember, other benign (not cancerous) conditions such as hemorrhoids and intestinal polyps commonly cause blood in the stool, so don’t panic. But do review these results with your physician.
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