Virtual colonoscopy — computed tomography (CT) imaging to build a three-dimensional representation of the bowel — can detect colon cancer as effectively as conventional methods, according to a study in The New England Journal of Medicine (4 December 2003). The procedure requires insertion of a small rectal catheter followed by a CT scan of the abdomen, and is cheaper, less invasive and less risky than conventional colonoscopy.

A team led by Perry Pickhardt of the University of Wisconsin screened 1,233 people aged between 50–79 using the virtual method, then compared the results with conventional colonoscopy carried out on the same day. Both procedures detected over 90% of polyps at least 8 mm in diameter, but one of the two malignant growths found by the virtual technique was missed by the conventional method. Chief Gastroenterologist at Beth Israel Medical School, Thomas Lamont, claims “It puts virtual colonoscopy right up there with the gold standard, optical colonoscopy” (The New York Times, 2 December 2003). Regular colonoscopy for the over 50s virtually eliminates the risk of colon cancer, but less than half of this population is screened. “If our methods are used, this will hopefully result in more widespread screening” suggests Pickhardt (Associated Press, 2 December 2003). But, conventional colonoscopy is still required to remove suspect polyps. “Since the patient has to go through the same preparation, which is the hardest part, they might as well do the conventional one” said Herman Kattlove, Medical Editor of the American Cancer Society (Associated Press, 2 December 2003).