Narrator: This is Science Today. Virtual colonoscopy, a non-invasive technique that uses X-rays delivered through a CT scanner, has been found to be effective in revealing disease outside of the colon, too. Dr. Judy Yee of the University of California , San Francisco , is chief of radiology at the San Francisco Veterans Affairs Medical Center .

Yee: What we found was that 63% of patients actually had a finding outside of the colon. Not all of those were significant. Nine percent had a significant finding. By that, what I mean is the finding actually led to an intervention. Either additional follow-up or actual surgery to have something removed.

Narrator: Yee says some of the findings they identified outside of the colon using virtual colonoscopy included lung cancers, kidney cancers and liver masses.

Yee: Because patients are not symptomatic for the problem that we have identified outside of the colon, we tend to identify disease outside of the colon at an earlier stage.

Narrator: For Science Today, I'm Larissa Branin.