THURSDAY, Jan. 28, 2010 (HealthDay News) -- Virtual colonoscopy is a safe and effective way to screen older patients for colorectal cancer, a new study indicates.
Researchers looked at the use of computed tomographic colonography (CTC) in 577 patients aged 65 to 79 and found it an effective way to screen for colorectal cancer in elderly patients. It produces low referral-for-colonoscopy rates that are similar to other screening tests covered by Medicare, and doesn't result in unreasonable levels of additional testing because of extracolonic findings, they noted.
"There have been questions raised that factors such as the [colonoscopy] referral rate and extracolonic work-up rates would be too high in an older population for CTC to be a cost-effective, frontline colorectal cancer screening exam. Our results suggest otherwise and that these rates remain in a reasonable range," principal investigator Dr. David H. Kim, an associate professor of radiology at the University of Wisconsin School of Medicine and Public Health, said in a news release.
Among the findings:
- Advanced neoplasia (abnormal growth) was detected in 7.6 percent (44 of 577) of patients. There was no statistically significant difference between the older patients and the general screening population in terms of the characteristics of advanced neoplasia. This indicates the accuracy is similar to that shown in studies involving younger patients.
- The overall referral rate to optical colonoscopy was 15.3 percent (88 of 577), which is slightly lower than other Medicare-covered colorectal cancer screening exams such as flexible sigmoidoscopy.
- Potentially significant extracolonic findings were seen in 15.4 percent (89 of 577) of patients, with a work-up rate of 7.8 percent (45) of patients. Most of the extracolonic diagnoses were vascular aneurysms.
- No major complications, such as colon perforations, occurred.
"The lack of complications, particularly no perforations, attests to the safety of this procedure even in the older population. Given what we know of the increasing risk for complications for optical colonoscopy in older patients, perhaps we should consider CT colonography more strongly in this particular group," said Kim.
The study is published in the February issue of Radiology.
The U.S. National Cancer Institute has more about colorectal cancer screening.