Screening important in fight against colon cancer Published March 25, 2011 By 72nd Medical Group General Surgery Clinic TINKER AIR FORCE BASE, Okla. -- "Who wants colon cancer?!" What, no hands are raised. Unfortunately, colon cancer is the third most common cancer in the U.S. This means about one out of every 20 people will get hit with this potentially preventable disease. Recently, the rates of colon cancer have declined -- likely due to earlier diagnosis by colonoscopy. What is colon cancer? As with any cancer, it is cells growing out of control. In this particular case, it's the cells that line the inside of the colon that are growing untamed. Generally speaking, colon cancers arise from polyps if the polyp is left in place long enough. If the cancer is left in place too long, it can spread to other parts of the body (metastasize) or invade parts of the body that are near it. How one gets a cancer (including colon) is not entirely clear. There are some things that we do that can make cancer more likely. The most obvious is smoking. Smoking increases your risk of just about every kind of cancer known. Your diet also contributes to your risk of colon cancer. In parts of the world where a very low fat, high fiber diet is consumed, colon cancer is almost rare. The most important predictor, however, is if you have a mother, father, sister, brother or child who had colon cancer. This is something you can't control and why screening is so important. Taking a fiber supplement that contains psyllium husk or calcium can decrease your chances of colon cancer. What is a colonoscopy and who needs one? For those of you in engine repair and maintenance, think of your borescope. For the rest of us, it is a digital camera that is on a long flexible tube. The tube is a little longer than the average person's arm -- about a yard -- and about ½ an inch across. Through the tube runs the electronics for the camera, a water channel to clean off the lens, two fiber optic lights and an open smaller tube. The smaller tube is used to wash away "debris" to see what's underneath, to take pieces of tissue to identify what they are and to pass instruments to remove things -- like polyps or biopsies -- that need to be taken out. The 6 inches of the tube nearest to the camera end are able to be turned by the doctor using dial controls at the other end. Most of the time, in the United States at least, people are sedated for colonoscopy. Here at Tinker, the vast majority of patients say they don't remember a thing about the colonoscopy itself. There are essentially three ways to screen for colon cancer: 1) Colonoscopy, 2) Fecal Occult Blood Testing (a chemical test for blood in bowel movements) with Flexible Sigmoidoscopy, or 3) Double Contrast Barium Enema, each one starting at 50 years old. The difference between colonoscopy and sigmoidoscopy is the distance that they go into the colon. A sigmoidoscope only goes in about 18 inches. Anything further up than that, it would miss. If something is found on the sigmoidoscopy or the barium enema then a follow up diagnostic colonoscopy is needed. Screening only happens if you are having no symptoms, but screening exams can prevent colon cancer. According to the National Comprehensive Cancer Network, colonoscopy is the preferred screening exam for colon cancer. One of the functions of colonoscopy is to remove polyps before they turn into a cancer. If you have a pre-cancerous polyp removed, you need to have a repeat colonoscopy sooner than if you hadn't had the polyp. If you are having symptoms (bleeding, black stools, thinning stools, new diarrhea, etc.) or have a family history of early colon cancer, you need a diagnostic colonoscopy. If you have symptoms, a family history of colon cancer, or another colon disorder, you should speak to your primary care provider about when you should start your examinations (it's usually much earlier). Finally, once a cancer is diagnosed surgery is the next stop. If it is a rectal cancer (at the very end of the colon), sometimes radiation and chemotherapy would happen first. Today, the surgery can be done laparoscopically if your surgeon has been trained to do this and the tumor size will allow it. The surgeon at Tinker AFB is capable of doing this. If you are 50 years old you should have a colonoscopy if you haven't had one already. The General Surgery Clinic on base is currently seeing military members and their families for colon cancer screening for age or related symptoms. For more information, you can go to WebMD.com, Tricare Online, contact the American Cancer Society or speak with your primary care provider at your next visit.