Providing data for serrated polyp detection rate benchmarks: an analysis of the New Hampshire Colonoscopy Registry

Abstract

Background and Aims Similar to achieving adenoma detection rate (ADR) benchmarks to prevent colorectal cancer (CRC), achieving adequate serrated polyp detection rates (SDR) may be essential to the prevention of CRC associated with the serrated pathway. Previous studies have been based on data from high-volume endoscopists at single academic centers. Based on a hypothesis that ADR is correlated with SDR, we stratified a large, diverse group of endoscopists (n=77 practicing at 28 centers) into high and low performers based on ADR, to provide data for corresponding target SDR benchmarks. Methods Using colonoscopies in adults ≥ 50 years (4/09–12/14), we stratified endoscopists by high and low ADR (< 15%,15% to <25%,25% to <35%, ≥35%), to determine corresponding SDRs, using two SDR measures, for screening and surveillance colonoscopies separately: (1) Clinically significant SDR (CSSDR) = colonoscopies with any SSA/P, TSA, HP >1 cm anywhere in the colon or HP > 5 mm in the proximal colon only ÷ by total screening and surveillance colonoscopies, respectively. (2) Proximal SDR (PSDR) = colonoscopies with any serrated polyp (SSA/P, HP, TSA) of any size proximal to the sigmoid ÷ by total screening and surveillance colonoscopies, respectively. Results A total of 45,996 (29,960 screening) colonoscopies by 77 endoscopists (28 facilities) were included. Moderately strong positive correlation coefficients were observed for screening ADR/CSSDR (ρ=0.69) and ADR/PSDR (ρ=0.79) and a strong positive correlation (ρ=0.82) for CSSDR/PSDR (p<0.0001 for all). For ADR ≥25%, endoscopists’ median (IQR) screening CSSDR was 6.8% (4.3%–8.6%) and PSDR was 10.8% (8.6% –16.1%). Conclusion Derived from ADR, the primary colonoscopy quality indicator, our results suggest potential SDR benchmarks (CSSDR=7% and PSDR=11%) that may guide adequate serrated polyp detection. Because CSSDR and PSDR are strongly correlated, endoscopists could use the simpler PSDR calculation to assess quality.

Factors Associated with Surveillance Adenoma and Sessile Serrated Polyp Detection Rates

“…The authors found a surveillance SSPDR of 10%, which is in the range of that found in our cohort (8%) [15]. A more recent multicenter study by Anderson and colleagues investigated proximal colon SSPDR for surveillance colonoscopy and found that among endoscopists with > 35% ADRs, median proximal SSPDR was 14.7% [10]. Our data are congruent as we also found that greater endoscopists’ screening ADR is associated with greater SSPDR.…”

“…The most recent benchmark for screening ADR is an average of 25% (women 20% and men 30%) [2]. Though there is currently no benchmark for sessile serrated polyp detection rate (SSPDR), prior studies have found varying rates, reporting up to 18% in screening examinations and up to 15% in surveillance examinations [8–10]. …”

A prospective RCT comparing combined chromoendoscopy with water exchange (CWE) vs water exchange (WE) vs air insufflation (AI) in adenoma detection in screening colonoscopy

“…33,34 Anderson et al believe a benchmark of 11% should be appropriate. 35 In the current study, the effectiveness of CWE and WE is well demonstrated by the significantly higher detection rate of the even more subtle proximal colon SLs by CWE (26.3%) and WE (23.6%) over AI (11.3%). By enhancing the outline of underlying lesions, chromoendoscopy does improve the detection of smaller SLs, especially in the proximal colon.…”

Terminology, Molecular Features, Epidemiology, and Management of Serrated Colorectal Neoplasia

“…45,62,73 Reviews of recently published colonoscopy series studies found that an average 2%-8% of SSLs are detected (akin to prevalence) in average-risk patients undergoing colonoscopy. 8,54,58,62,[73][74][75][76][77][78][79][80][81][82] Among high-detecting endoscopists and centers, however, the reported prevalence values are 13%-20% ( Figure 3A, Supplementary Table 2). 45,54,62,74,78 It is a reasonable assumption that detection of SSLs among high detectors is the best estimate of the true prevalence of these lesions.…”