Colonic surveillance, as opposed to screening, is the periodic examination of the colon after polyps and/or cancer has been identified. It is currently estimated that less than 30 percent of the American population age 50 and older has been screened for CRC. It's essential to note that the recent study by Mysliwiec1 in the Annals of Internal Medicine does not suggest that there are too many initial screening colonoscopies being performed at present.
Rather, the study suggests that too many surveillance colonoscopies are performed. The American Gastroenterological Association disputes the validity of this conclusion.
The Annals study is based on physician's self-reporting practice patterns based on hypothetical cases. Because this study does not contain clinical detail, physicians may over or underestimate their own clinical behavior. Many guidelines currently exist for colon polyp surveillance. The appropriate time interval for surveillance is influenced by many factors (type of polyp, size, number and the adequacy of the colonic prep).
An important issue raised in the study is what is the clinical significance of the small polyp? The guidelines proposed by the AGA and a consortium of GI societies could not provide recommendations for their surveillance due to the lack of scientific studies to define the appropriate behavior. Therefore, it is wrong to judge inappropriate the actions of physicians who performed surveillance colonoscopies on patients with small polyps.
The National Cancer Institute, which funded this study, should take the logical next step and fund a long-term study of the natural history of the small polyp. Applying the knowledge generated by such a study could positively impact the very real public health issues of the cost of colorectal cancer surveillance and clinical care strategies for small polyps.
1Mysliwiec, P. et al. Ann Intern Med. 2004; 141:264-271
About the AGA
The AGA is dedicated to the mission of advancing the science and practice of gastroenterology. Founded in 1897, the American Gastroenterological Association is the oldest medical-specialty society in the United States. The AGA's 14,000 members include physicians and scientists who research, diagnose and treat disorders of the gastrointestinal tract and liver. On a monthly basis, the AGA publishes two highly respected journals, Gastroenterology and Clinical Gastroenterology and Hepatology. The AGA's annual meeting is Digestive Disease Week, which is held each May and is the largest international gathering of physicians, researchers and academics in the fields of gastroenterology, hepatology, endoscopy and gastrointestinal surgery. More information about the AGA is available at http://www.gastro.org.
Journal
Annals of Internal Medicine