In many ways, the colon is the body’s trash compactor. This 5-foot-long, muscular organ, also called the large intestine, absorbs water from food and readies waste for elimination through a final 6-inch stretch called the rectum. The colon is also the third-most-common site for cancer to take hold: Cancers of the colon or rectum (called colorectal cancer) strike 1 in 20 people, with more than 155,000 new cases in the United States every year.

Like all other tissues, colon cells constantly grow and divide in an orderly fashion to replace old and worn-out cells. But in some cases, this process can veer off track, and cells can multiply even when new ones aren’t necessary. This unchecked growth most commonly develops into a polyp, a tissue mass attached to the intestinal lining. Once a polyp forms, it often takes several years for these irregular cells to mutate and become cancerous. In its later stages, the cancer can spread to other organs in the body and to the lymph nodes; as a result, colorectal cancer is the second-most-frequent cause of cancer death (after lung cancer).

Fortunately, if caught early on, colorectal cancers are highly treatable with surgery. For more advanced cancers, chemotherapy is necessary. Symptoms of the disease include abdominal pain, bloody stools, fatigue, and unexplained weight loss. To diagnose colorectal cancer, physicians can administer a stool test and perform a barium enema, which uses an x-ray to screen for polyps or cancerous growths. A colonoscopy, in which a physician inserts a flexible tube attached to tiny camera to examine the inside of the colon, is recommended every 10 years starting at age 50. The television news anchor Katie Couric (1957–), whose husband died of colon cancer, publicized this routine screening in a Today show segment in 2000. In the months after the segment aired, the number of colonoscopies jumped by more than 20 percent—something experts dubbed the Katie Couric effect.

ADDITIONAL FACTS

  1. As with most other cancers, lifestyle changes can lower the risk of developing colon cancer. Research shows that eating a diet high in whole grains, fruits, and vegetables and low in saturated fats slashes the risk of the disease.
  2. Scientists have uncovered cancers in the remains of dinosaurs that lived more than 200 million years ago.
  3. The first successful surgery for colon cancer was performed in 1829 by the Parisian surgeon Jacques Lisfranc (1790–1847).