What is the ideal method for colon cancer screening? What is the best interval between colorectal cancer screenings? How virtual colonoscopy and regular colonoscopy compare in cancer finding sensitivity? Leading virtual colonoscopy screening expert discusses CT colonography. Virtual colonoscopy.

Virtual colonoscopy can detect precancerous and early colon cancer lesions. CT colonography does this with even greater accuracy than optical colonoscopy. Dr. Anton Titov, MD. It is especially true for lesions at the right side of colon. Please compare how virtual colonoscopy and optical colonoscopy differ. Dr. Anton Titov, MD. What is their ability to detect colon cancer at different locations along the large bowel? Dr. Perry Pickhardt, MD. Yes. CT colonography and regular colonoscopy are fairly complementary. Because CT colonography seems to have an advantage in the right side of colon. Right side of large bowel is further away from the fiberoptic endoscope. But right side of large bowel is more distensible. It has a more capacious area for us to do a 3D fly-through during virtual colonoscopy computer analysis. We have no restrictions evaluating the right side of colon (large bowel). We tend to have more difficulty in the left side of colon. Dr. Perry Pickhardt, MD. On the left side of colon, a diverticular disease may narrow the colon lumen. It can cause some difficulty for virtual colonoscopy analysis. Dr. Anton Titov, MD. The opposite is true for regular colonoscopy. Optical colonoscopy tends to do better in the left side of colon. This is easier to access. But then optical colonoscopy has more difficulty reaching over the right side of large bowel. Dr. Perry Pickhardt, MD. Optical colonoscopy struggles to look around every single fold in the right side of colon. I've often considered that the perfect strategy for colon cancer screening is this. CT colonography alternating with flexible sigmoidoscopy every 5 or 10 years. This would provide the benefits of both left-sided and right-sided detection of colorectal cancer and precancerous lesions. Dr. Perry Pickhardt, MD. CT colonography does well enough in the left side of colon. Virtual colonoscopy is really a one-stop shop for colon cancer screening. This would be a very interesting strategy indeed. Because it takes about 10 years for the polyps to grow and become advanced neoplasia. It takes a long time polyps to become precancerous or early colon cancer lesions. Dr. Perry Pickhardt, MD. Yes, that is correct. There are some interesting complementary benefits from using both virtual and optical regular colonoscopy. Dr. Anton Titov, MD. Flexible sigmoidoscopy, of course, is much less invasive than full optical colonoscopy in terms of what's needed for sedation of patient and recovery time. But I still would favor a full CT colonography every 5 to 10 years as the preferred method. Virtual colonoscopy advantages in detecting cancer on the right side of bowel. Can virtual colonoscopy detect Crohn’s disease and ulcerative colitis? how virtual colonoscopy and optical regular colonoscopy compare in the ability to detect colon cancer at different locations of large bowel? Virtual colonoscopy has no restrictions to evaluate the right side of large bowel. perfect colorectal cancer screening strategy might be CT colonography alternating with flexible sigmoidoscopy every 5 or 10 years. flexible sigmoidoscopy, of course, is much less invasive than full optical colonoscopy.