According to the American Cancer Society, colon cancer is the second leading cause of cancer-related death in the United States. The average adult has about a 1 in 20 chance of being diagnosed with colon cancer, although this varies widely, depending on individual risk factors. Even though colon cancer is on the rise in the US (an estimated 140,250 new cases in 2019), it is relatively treatable when caught early, which is why colon cancer screening is so important.
Colon cancer screening starts with reviewing a patient’s medical history and family tree. If the patient has a personal or family history of colon cancer, their chances of having this disease rise exponentially. This review is followed by a colonoscopy, where a physician will examine the colon and rectum, and search for signs of cancerous polyps and areas of concern.
The American Cancer Society recommends that patients at average risk get screening colonoscopies every ten years beginning at age 50, or every five years starting at age 45 if they have a family or personal history of colon cancer or polyps, as mentioned above.
Polyps are abnormal tissue growths that are often small, flat bumps, less than half an inch wide. In some cases, polyps develop in the colon and can be malignant (cancerous). However, this is not always the case. In fact, many people develop polyps, and in most cases, they are benign (non-cancerous). Frequently polyps don’t exhibit symptoms until they have grown very large, so frequent colonoscopies are the best way to detect them while they are small and very treatable.
It is often said that preparation is the hardest part of a colonoscopy. Before the procedure, patients will need to fast and drink a special liquid or take medication to help empty the bowels. On the day of the exam, sedation is administered intravenously by an anesthesiologist, so that the patient will be relaxed throughout the procedure. They lay on their left-hand side on an exam table during the procedure, and a thin, flexible colonoscope is inserted into the anus and passed through the rectum and large intestine. Air is then introduced gradually to expand the narrowed areas so that the physician can more easily see the video images that are projected onto the monitor from a special camera at the end of the colonoscope. As it moves through the colon, the doctor can pinpoint any troubling areas. If he or she wishes, they can biopsy any abnormal areas found during the colonoscopy. A biopsy is when a small sample is taken of the tissue or polyp(s) to test and determine whether it is cancerous (malignant) or not (benign). A special instrument is then passed through the colonoscope to gather the samples. The tissue is then sent to a lab for evaluation. Colonoscopies are typically very safe, and only take about a half-hour.