Virtual colonoscopy catches more cancers
Colonoscopy is an important tool to detect colorectal cancer. In recent years, virtual colonoscopy, which involves a CT scan of the colon instead of the invasive, optical inspection of the colon, has been shown to be as effective as traditional colonoscopy. Now, a new study suggests that virtual colonoscopy may even be superior because it can identify cancers outside of the colon.

In a study of 2,277 patients who underwent virtual colonoscopy, almost half were found to have some suspicious lesions outside the colon. Further testing showed that 240 of those lesions were considered medically significant, such as being some type of cancer. After further evaluation, 19 surgeries were performed to identify six cancers (one lymphoma, three renal cell cancers and two lung cancers) and one aortic aneurysm.

Virtual colonoscopy essentially allows for an examination of the entire abdomen and pelvis, unlike traditional colonoscopy, which is limited to the interior of the colon and rectum. While virtual colonoscopy is not as accurate as a regular CT scan of the abdomen for identifying cancers in the abdomen, it's ability to pick up some types of cancers outside the colon while primarily looking for colorectal cancer make it an attractive alternative to traditional colonoscopy, the authors, from Walter Reed Army Medical Center, stated.

The obvious problem with this approach, however, is the extra cost of having to explore suspicious lesions outside the colon (that may turn out to be nothing significant) and the resulting anxiety felt by patients who have to undergo further testing. The study's authors suggest that the minimal additional cost may be worth it to identify other types of cancer.

The study was released Friday in the American Journal of Roentgenology.