A comparison of the adenoma detection rate (ADR) and multiple adenoma detection rate metrics in an Australian cohort: The utility of the mean adenomas per procedure (MAP), mean adenomas per positive procedure (MAP+) and adenoma detection rate-plus (ADR+).

Abstract

Background: There has been much interest recently on the use of objective measures for the adequacy of colonoscopy. These include bowel preparation, caecal intubation rate and adenoma detection rate (ADR). There is a suggestion that the ADR may not be an adequate measure of adenoma detection as it could potentially enhance a 'one and done' phenomenon where colonoscopists receive the same ADR for achieving one or multiple polyps on each individual colonoscopy. As each adenoma carries a prospective cancer risk, a colonoscopist that detects multiple adenomas per colonoscopy is likely to decrease a patient's interval cancer rate [1,2]. The multiple adenoma detection rate matrices (ADR+, MAP and MAP+) have been proposed as an index which could be a useful adjunct to colonoscopic adequacy [1,2]. However, little is known of what these matrices add to assessing colonoscopic quality, as data is currently insufficient, however a ADR+ target of 0.8 has been proposed [1]. This study presents the largest cohort of Australian patients to date for which multiple adenoma detection matrices have been calculated. Aim(s): To analyze and compare the multiple adenoma detection rate metrics to the traditionalADR for patients undergoing routine screening or surveillance colonoscopy in Australia Methods: A retrospective study was performed from prospectively collected data from three day endoscopy centers involving four experienced gastroenterologists. Over twelve hundred procedures were identified. Exclusion criteria included a previously performed partial or total colectomy or in the case of multiple endoscopies, having a previous colonoscopy within the study period. Result(s): A total of 1119 procedures were analyzed. Participants had an average age of 59.6 years, with 53.8% being female. The adenoma detection rate that was calculated totaled 20.73% (27% for men and 14.9% for women), with a slightly improved rate of 21.06% for those patients over 50 years of age. TheADR+ rate calculated was 0.55. The Mean Adenomas per Procedure (MAP) was 0.28, with the Mean Adenomas per Positive Procedure (MAP+) equal to 1.52. Conclusion(s): This study describes for the first time the multiple adenoma detection rate indices in a large cohort of patients undergoing colonoscopy in Australia. The need for further studies, preferably using pooled data from multiple centres to assess the utility of using these indices as an adjunctive measure of colonoscopy quality should now be recognized. (Table Presented).