The Laxative-Free 'Virtual Colonoscopy'
Eliminating the Need for Bowel Prep Could Spur More People to Get Screened for Colon Cancer
Virtual Colonoscopy Uncommon
Although virtual colonoscopy eliminates another off-putting aspect of conventional colonoscopy -- the need to insert a long, thin tube called a colonoscope through the entire length of the colon -- relatively few Americans have opted for the procedure.
In 2010, only about 1 in 100 Americans aged 50-75 reported ever having a virtual colonoscopy, according to CDC and National Cancer Institute data published this month.
In 2008, the American Cancer Society endorsed CT colonography every five years as an acceptable colon screening method. But Medicare doesn't routinely cover the procedure, Zalis says. "Appropriately, there's a high bar placed on screening."
Private insurers tend to follow Medicare's lead, so virtual colonoscopy is not widely reimbursed. As a result, Zalis says, relatively few doctors have learned how to do it.
Zalis says Massachusetts General is not yet promoting laxative-free CT colonography because his findings need to be confirmed by other researchers. However, he says, if a patient who's never been screened asks about having a laxative-free colonography, "we'd definitely do the exam."
The findings of Zalis' study are "intriguing," says gastroenterologist Samir Gupta, MD, an assistant professor of internal medicine at the University of Texas Southwestern Medical Center in Dallas.
"The game-changer for CT colonography would be if they could do minimal prep, laxative-free exams and have high sensitivity for most polyps and cancers," Gupta says. "I think this study is a very good proof-of-concept study. But it's not ready for prime time."
Zalis' study appears in the current issue of the Annals of Internal Medicine.