According to a report published by Pickhardt et al in the American Journal of Roentgenology (AJR), compared with multitarget stool DNA and fecal immunochemical tests, computed tomography (CT) colonography using a polyp size threshold ≥ 10 mm most effectively targeted advanced neoplasia—preserving detection while decreasing unnecessary colonoscopies.
“CT colonography performed with a polyp size threshold for colonoscopy referral set at ≥ 10 mm represents the most effective and efficient noninvasive screening test for colorectal cancer prevention and detection,” said first study author Perry J. Pickhardt, MD, of the Department of Radiology at the University of Wisconsin School of Medicine & Public Health.
Perry J. Pickhardt, MD
Meta-analysis
Because the relative performance characteristics of available noninvasive tests had not yet been adequately compared, researchers systematically searched PubMed and Google Scholar and compiled data on 10 published screening studies of multitarget stool DNA, 27 studies of CT colonography, and 88 studies of fecal immunochemical tests, involving 25,132; 33,4932; and 2,355,958 asymptomatic adults, respectively. To determine test-positivity rates leading to optical colonoscopy, as well as positive predictive value and detection rate for both advanced neoplasia and colorectal cancer, meta-analysis with hierarchical Bayesian modeling was conducted, in accordance with Cochrane Collaboration and PRISMA guidelines.
Results
Results showed that colorectal cancer prevention via screen detection of advanced neoplasia was highest with CT colonography, followed by multitarget stool DNA, and lowest with fecal immunochemical tests due to the differing test-positivity rates and positive predictive value, although overlap existed in the 95% confidence intervals. Compared with multitarget stool DNA and CT colonography with a 6-mm threshold, strategies using fecal immunochemical tests and CT colonography with a 10-mm threshold yielded substantially lower colonoscopy resource utilization, while multitarget stool DNA performance appeared to be similar to fecal immunochemical tests at low positivity thresholds.
Acknowledging that each colorectal cancer screening option has relative advantages and disadvantages that should be carefully considered and tailored to the individual, “In the end, the ‘best’ test may be the one that the patient is willing to undergo,” said the study authors.
Disclosure: For full disclosures of the study authors, visit ajronline.org.
