PIVI document examines endoscopic assessment of diminutive colorectal polyps

Mar 9 2011

In recognition of National Colorectal Cancer Awareness Month during March, GIE: Gastrointestinal Endoscopy has put out a special issue for March on colonoscopy and colorectal cancer. In this issue is the first statement from a new initiative by the American Society for Gastrointestinal Endoscopy (ASGE) called the Preservation and Incorporation of Valuable Endoscopic Innovations (PIVI). The first PIVI document examines real-time endoscopic assessment of the histology of diminutive (≤ 5 mm in size) colorectal polyps and is one in a series of statements defining the diagnostic or therapeutic threshold that must be met for a technique or device to become considered appropriate for incorporation into clinical practice. GIE: Gastrointestinal Endoscopy is the monthly peer-reviewed scientific journal of the American Society for Gastrointestinal Endoscopy (ASGE).

"In addition to defining thresholds for when a new technique or device is ready for use in clinical practice, PIVI statements are meant to serve as a guide for researchers or those seeking to develop technologies that are designed to improve digestive health outcomes," said M. Brian Fennerty, MD, FASGE, president, American Society for Gastrointestinal Endoscopy. "The purpose of the first PIVI is to focus efforts by clinicians and industry toward development of new paradigms for the colonoscopic management of diminutive polyps that minimize risk and unnecessary delay of information to patients while improving the cost effectiveness of colonoscopy. The PIVI's recommended thresholds for performance standards of technologies should serve investigators by establishing the correct group of target lesions in which to examine technologies that purport to allow real-time determination of histology, to create clinical endpoints in trials that are meaningful and relevant, and to estimate the required sample sizes for adequately powered studies."

Diminutive polyps are extremely common, with recent studies employing high definition colonoscopes identifying diminutive adenomas (precancerous polyps) in about half and diminutive polyps in more than half of the U.S. screening population. A much smaller fraction of the U.S. population develops colorectal cancer, and polyps larger than 5 mm in size are more likely than diminutive polyps to harbor cancer or advanced neoplasia, or to eventually develop into colorectal cancer. Current practice of colonoscopic management of diminutive polyps is generally to resect (remove) and submit them for pathologic assessment, however, the routine pathological assessment of all resected diminutive colorectal polyps results in substantial costs to patients and society for management of a group of lesions with limited clinical importance. Pathological assessment also causes a delay for informing patients of the histology of their polyps and in recommending the next colonoscopy surveillance interval.

The PIVI committee (consisting of a committee of ASGE physician experts) performed a literature review. Factors that were considered in reaching consensus regarding the recommended thresholds included the importance of the issue to clinical practice, the accuracy of the gold standard (pathology), and the impact of other factors that affect clinical outcomes. The PIVI is provided solely for educational and informational purposes and to support incorporating these endoscopic technologies into clinical practice. It should not be construed as establishing a legal standard of care.

Source: American Society for Gastrointestinal Endoscopy