Significant Variation in the Detection Rates of Proximal Serrated Polyps Among Academic Gastroenterologists, Community Gastroenterologists, and Colorectal Surgeons in a Single Tertiary Care Center

Association Between Endoscopist Specialty and Colonoscopy Quality: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Colonoscopy quality indicators provide measurable assessments of performance, but significant provider-level variations exist. We performed a systematic review and meta-analysis to assess whether endoscopist specialty is associated with adenoma detection rate (ADR) - the primary outcome - or cecal intubation rate, adverse event rates, and post-colonoscopy colorectal cancer rates.

METHODS

We searched EMBASE, Google Scholar, MEDLINE, and the Cochrane Central Registry of Controlled Trials from inception to December 14, 2020. Two reviewers independently screened titles and abstracts. Citations underwent duplicate full-text review, with disagreements resolved by a third reviewer. Data were abstracted in duplicate. The DerSimonian and Laird random effects model was used to calculate pooled odds ratios (ORs) with respective 95% confidence intervals (CIs). Risk of bias was assessed using Risk of Bias in Non-randomised Studies of Interventions.

RESULTS

Of 11,314 citations, 36 studies representing 3,500,832 colonoscopies were included. Compared with colonoscopies performed by gastroenterologists, those by surgeons were associated with lower ADRs (OR, 0.81; 95% CI, 0.74-0.88) and lower cecal intubation rates (OR, 0.76; 95% CI, 0.63-0.92). Compared with colonoscopies performed by gastroenterologists, those by other (non-gastroenterologist, non-surgeon) endoscopists were associated with lower ADRs (OR, 0.91; 95% CI, 0.87-0.96), higher perforation rates (OR, 3.02; 95% CI, 1.65-5.51), and higher post-colonoscopy colorectal cancer rates (OR, 1.23; 95% CI, 1.14-1.33). Substantial to considerable heterogeneity existed for most analyses, and overall certainty in the evidence was low according to the Grading of Recommendations, Assessment, Development, and Evaluations framework.

CONCLUSION

Colonoscopies performed by surgeons or other endoscopists were associated with poorer quality metrics and outcomes compared with those performed by gastroenterologists. Targeted quality improvement efforts may be warranted.

Clinically significant serrated polyp detection rates and risk for postcolonoscopy colorectal cancer: data from the New Hampshire Colonoscopy Registry

BACKGROUND AND AIMS

Higher adenoma detection rates reduce the risk of postcolonoscopy colorectal cancer (PCCRC). Clinically significant serrated polyps (CSSPs; defined as any sessile serrated polyp, traditional serrated adenoma, large [≥1 cm] or proximal hyperplastic polyp >5 mm) also lead to PCCRC, but there are no data on associated CSSP detection rates (CSSDRs). We used data from the New Hampshire Colonoscopy Registry (NHCR) to investigate the association between PCCRC risk and endoscopist CSSDR.

METHODS

We included NHCR patients with 1 or more follow-up events: either a colonoscopy or a colorectal cancer (CRC) diagnosis identified through linkage with the New Hampshire State Cancer Registry. We defined our outcome, PCCRC, in 3 time periods: CRC diagnosed 6 to 36 months, 6 to 60 months, or all examinations (6 months or longer) after an index examination. We excluded patients with CRC diagnosed at or within 6 months of the index examination, with incomplete examinations, or with inflammatory bowel disease. The exposure variable was endoscopist CSSDR at the index colonoscopy. Cox regression was used to model the hazard of PCCRC on CSSDR controlling for age, sex, index findings, year of examination, personal history of colorectal neoplasia, and having more than 1 surveillance examination.

RESULTS

One hundred twenty-eight patients with CRC diagnosed at least 6 months after their index examination were included. Our cohort included 142 endoscopists (92 gastroenterologists). We observed that the risk for PCCRC 6 months or longer after the index examination was significantly lower for examinations performed by endoscopists with CSSDRs of 3% to <9% (hazard ratio [HR], .57; 95% confidence interval [CI], .39-.83) or 9% or higher (HR, .39; 95% CI, .20-.78) relative to those with CSSDRs under 3%.

CONCLUSIONS

Our study is the first to demonstrate a lower PCCRC risk after examinations performed by endoscopists with higher CSSDRs. Both CSSDRs of 9% and 3% to <9% had statistically lower risk of PCCRC than CSSDRs of <3%. These data validate CSSDR as a clinically relevant quality measure for endoscopists.

Improving sessile serrated adenoma detection rates with high definition colonoscopy: A retrospective study

BACKGROUND

Sessile serrated adenomas (SSAs) are important premalignant lesions that are difficult to detect during colonoscopy due to poor definition, concealment by mucous caps, and flat appearance. High definition (HD) colonoscopy may uniquely aid in the detection of these inconspicuous lesions compared to standard definition (SD) colonoscopes. In the absence of existing clinical guidelines to obligate the use of HD colonoscopy for colorectal cancer screening in average-risk patients, demonstrating the benefit of HD colonoscopy on SSA detection rate (SSADR) may help strengthen the evidence to recommend its use in all settings.

AIM

To evaluate the benefit of HD colonoscopy compared to SD colonoscopy on SSADR in average-risk patients undergoing screening colonoscopy.

METHODS

Data from screening colonoscopies for patients aged 50-76 years two years before and two years after the transition from SD colonoscopy to HD colonoscopy at our large, academic teaching center were collected. Patients with symptoms of colorectal disease, positive occult blood test, history of colon polyps, cancer, polyposis syndrome, inflammatory bowel disease or family history of colon cancer or polyps were excluded. Patients whose endoscopists did not perform colonoscopies both before and after scope definition change were also excluded. Differences in individual endoscopist SSADR, average SSADR, and overall SSADR with SD colonoscopy vs HD colonoscopy were also evaluated for significance.

RESULTS

A total of 3657 colonoscopies met eligibility criteria with 2012 colonoscopies from the SD colonoscopy period and 1645 colonoscopies from the HD colonoscopy period from a pool of 11 endoscopists. Statistically significant improvements of 2.30% in mean SSADR and 2.53% in overall SSADR were noted with HD colonoscopy (P = 0.00028 and P = 0.00849, respectively). On the individual level, three endoscopists experienced statistically significant benefit with HD colonoscopy (+5.74%, P = 0.0056; +4.50%, P = 0.0278; +4.84%, P = 0.03486).

CONCLUSION

Our study suggests that HD colonoscopy statistically significantly improves sessile serrated adenoma detection rate in the screening of average risk patients during screening colonoscopy. By improving the detection and removal of these lesions, adoption of HD colonoscopy may reduce the significant premalignant burden of sessile serrated adenomas.

Improving sessile serrated adenoma detection rates with high definition colonoscopy: A retrospective study

BACKGROUND

Sessile serrated adenomas (SSAs) are important premalignant lesions that are difficult to detect during colonoscopy due to poor definition, concealment by mucous caps, and flat appearance. High definition (HD) colonoscopy may uniquely aid in the detection of these inconspicuous lesions compared to standard definition (SD) colonoscopes. In the absence of existing clinical guidelines to obligate the use of HD colonoscopy for colorectal cancer screening in average-risk patients, demonstrating the benefit of HD colonoscopy on SSA detection rate (SSADR) may help strengthen the evidence to recommend its use in all settings.

AIM

To evaluate the benefit of HD colonoscopy compared to SD colonoscopy on SSADR in average-risk patients undergoing screening colonoscopy.

METHODS

Data from screening colonoscopies for patients aged 50-76 years two years before and two years after the transition from SD colonoscopy to HD colonoscopy at our large, academic teaching center were collected. Patients with symptoms of colorectal disease, positive occult blood test, history of colon polyps, cancer, polyposis syndrome, inflammatory bowel disease or family history of colon cancer or polyps were excluded. Patients whose endoscopists did not perform colonoscopies both before and after scope definition change were also excluded. Differences in individual endoscopist SSADR, average SSADR, and overall SSADR with SD colonoscopy vs HD colonoscopy were also evaluated for significance.

RESULTS

A total of 3657 colonoscopies met eligibility criteria with 2012 colonoscopies from the SD colonoscopy period and 1645 colonoscopies from the HD colonoscopy period from a pool of 11 endoscopists. Statistically significant improvements of 2.30% in mean SSADR and 2.53% in overall SSADR were noted with HD colonoscopy (P = 0.00028 and P = 0.00849, respectively). On the individual level, three endoscopists experienced statistically significant benefit with HD colonoscopy (+5.74%, P = 0.0056; +4.50%, P = 0.0278; +4.84%, P = 0.03486).

CONCLUSION

Our study suggests that HD colonoscopy statistically significantly improves sessile serrated adenoma detection rate in the screening of average risk patients during screening colonoscopy. By improving the detection and removal of these lesions, adoption of HD colonoscopy may reduce the significant premalignant burden of sessile serrated adenomas.

A Polyp Worth Removing: A Paradigm for Measuring Colonoscopy Quality and Performance of Novel Technologies for Polyp Detection

Leaving no significant polyp behind while avoiding risks due to unnecessary resections is a commonsense strategy to safely and effectively prevent colorectal cancer (CRC) with colonoscopy. It also alludes to polyps worth removing and, therefore, worth finding. The majority of "worthy" precancerous polyps are adenomas, which for over 2 decades, have received the most attention in performance research and metrics. Consequently, the detection rate of adenomas is currently the only validated, outcome-based measure of colonoscopy demonstrated to correlate with reduced risk of postcolonoscopy CRC. However, a third or more of postcolonoscopy CRCs originate from sessile serrated polyps (SSPs), which are notoriously difficult to find, diagnose and completely resect. Among serrated polyps, the agreement among pathologists differentiating SSPs from non-neoplastic hyperplastic polyps is moderate at best. This lack of ground truth precludes SSPs from consideration in primary metrics of colonoscopy quality or performance of novel polyp detection technologies. By instead leveraging the distinct endoscopic and clinical features of serrated polyps, including those considered important due to proximal location and larger size, clinically significant serrated polyps represent serrated polyps worth removing, enriched with subtle precancerous SSPs. With the explosion of technologies to assist polyp detection, now is the time to broaden benchmarks to include clinically significant serrated polypss alongside adenomas, a measure that is relevant both for assessing the performance of endoscopists, and for assessing new polyp detection technologies.

Correlation between proximal serrated polyp detection and clinically significant serrated polyps: inter-endoscopist variability

INTRODUCTION AND AIMS

The adenoma detection rate (ADR) is the most important quality indicator for the prevention of colorectal cancer but serrated polyps are also precursor lesions of the disease. The aim of our study was to compare the detection rate of proximal serrated polyps (PSPs) and that of clinically significant serrated polyps (CSSPs) between endoscopists and analyze the relation of those parameters to the ADR.

METHODS

An observational, prospective, cross-sectional study was conducted on all patients that underwent colonoscopy at the Policlínico Peruano Japonés within the time frame of July 2015 and August 2016. The ADR and PSP and CSSP detection rates between endoscopists were compared through multivariate logistic regression and the association between those parameters was calculated through the Pearson correlation coefficient.

RESULTS

The study included 15 endoscopists and 1,378 colonoscopies. The PSP detection rate ranged from 1.8-17% between endoscopists and had an almost perfect correlation with the CSSP detection rate (p = 0.922), as well as strongly correlating with the ADR (p = 0.769).

CONCLUSIONS

There was great variability in the PSP detection rate between endoscopists. It also had an almost perfect correlation with the CSSP detection rate and strongly correlated with the ADR. Those results suggest a high CSSP miss rate at endoscopy and a low PSP detection rate.

Sessile serrated lesion detection rates during average risk screening colonoscopy: A systematic review and meta-analysis of the published literature

Background and study aims  Sessile serrated lesion (SSL) detection rate has been variably reported and unlike adenoma detection rate (ADR) is not currently a quality indicator for screening colonoscopy. Composite detection rates of SSL in patients undergoing average risk screening colonoscopy are not available. Methods  Electronic database search (Medline, Embase and Cochrane) was conducted for studies reporting detection rates of serrated polyps (SSL, Hyperplastic polyp, traditional serrated adenoma) among average risk subjects undergoing screening colonoscopy. Primary outcomes were pooled SDR (SSL detection rate) and proximal serrated polyp detection rate (PSPDR). Pooled proportion rates were calculated with 95 %CI with assessment of heterogeneity (I ² ). Publication bias, regression test and 95 %prediction interval were calculated. Results  A total of 280,370 screening colonoscopies among average risk subjects that were eligible with 48.9 % males and an average age of 58.7 years (± 3.2). The pooled SDR was available from 16 studies: 2.5 % (1.8 %-3.4 %) with significant heterogeneity (I ²  = 98.66 %) and the 95 % prediction interval ranging from 0.6 % to 9.89 %. When analysis was restricted to large (n > 1000) and prospective studies (n = 4), SDR was 2 % (1.1 %-3.3 %). Pooled PSPDR was 10 % (8.5 %-11.8 %; 12 studies). There was evidence of publication bias ( P  < 0.01). Conclusion  Definitions of SSL have been varying over years and there exists significant heterogeneity in prevalence reporting of serrated polyps during screening colonoscopy. Prevalence rate of 2 % for SSL and 10 % for proximal serrated polyps could serve as targets while robust high-quality data is awaited to find a future benchmark showing reduction in colorectal cancer arising from serrated pathway.

From Mixed Hyperplastic/Adenomatous Polyp to Sessile Serrated Lesion: A Long and Winding Road for Long and Winding Crypts

CONTEXT.—

During the past 3 decades, numerous articles in the literature have offered terminology, diagnostic criteria, and consensus recommendations regarding the entity currently referred to by the World Health Organization as sessile serrated lesion. Given the many names and various, variably reproducible diagnostic criteria ascribed to sessile serrated lesion, confusion persists for many pathologists and gastroenterologists regarding the diagnosis. This distinction is important, as sessile serrated lesion can progress to malignancy, unlike its main differential diagnosis, hyperplastic polyp. Research studies have shed light on the characteristic architecture and morphology, immunohistochemical patterns, and molecular alterations of sessile serrated lesion, and multiple consensus meetings around the globe have developed their criteria and nomenclature, often clashing or mixing terms.

OBJECTIVE.—

To provide a narrative review from the entity's early description to our current understanding.

DATA SOURCES.—

The existing scientific and clinical literature, published texts, medical society recommendations, and specialty consensus guidelines.

CONCLUSIONS.—

The current World Health Organization criteria are a distillation of this scientific process, but terminology is still a point of contention worldwide.

Correlation between proximal serrated polyp detection and clinically significant serrated polyps: inter-endoscopist variability

INTRODUCTION AND AIMS

The adenoma detection rate (ADR) is the most important quality indicator for the prevention of colorectal cancer but serrated polyps are also precursor lesions of the disease. The aim of our study was to compare the detection rate of proximal serrated polyps (PSPs) and that of clinically significant serrated polyps (CSSPs) between endoscopists and analyze the relation of those parameters to the ADR.

METHODS

An observational, prospective, cross-sectional study was conducted on all patients that underwent colonoscopy at the Policlínico Peruano Japonés within the time frame of July 2015 and August 2016. The ADR and PSP and CSSP detection rates between endoscopists were compared through multivariate logistic regression and the association between those parameters was calculated through the Pearson correlation coefficient.

RESULTS

The study included 15 endoscopists and 1,378 colonoscopies. The PSP detection rate ranged from 1.8-17% between endoscopists and had an almost perfect correlation with the CSSP detection rate (p = 0.922), as well as strongly correlating with the ADR (p = 0.769).

CONCLUSIONS

There was great variability in the PSP detection rate between endoscopists. It also had an almost perfect correlation with the CSSP detection rate and strongly correlated with the ADR. Those results suggest a high CSSP miss rate at endoscopy and a low PSP detection rate.

Colorectal Cancer Screening for the Serrated Pathway

Serrated polyps are classified into hyperplastic polyps, sessile serrated adenomas/polyps, and traditional serrated adenomas. Although all serrated polyps share characteristic colonic crypts serrations, distinguishing hyperplastic polyps from sessile serrated adenomas/polyps is challenging. Traditional serrated adenomas are cytologically dysplastic lesions; sessile serrated adenomas/polyps develop cytologic dysplasia as they progress to colorectal cancer. A flat and pale appearance of serrated polyps may make detection difficult. Endoscopic mucosal resection has higher rates of complete resection. Close surveillance is recommended for sessile serrated adenomas/polyps, sessile serrated adenomas/polyp with dysplasia, hyperplastic polyps ≥10 mm, and traditional serrated adenomas.

Automated imaging cytometry reveals dysplastic indices of colonic serrated adenomas

Aim:

Left-sided colonic serrated adenomas (L-SAs) were evaluated for aneuploidy using automated imaging cytometry to quantify DNA content and compared with normal colonic tissues (NCT), tubular adenomas (TA), left-sided hyperplastic polyps (L-HP) and adenocarcinomas.

Materials & methods:

We used standard paraffin-embedded Feulgen-stained tissue sections.

Results:

The mean DNA index (DI) of NCT was 0.95, L-HP was 1.08, TA was 1.22, L-SA was 1.11 and adenocarcinomas was 1.46. DI of L-SA was statistically higher than that of NCT, but not statistically different from L-HP.

Conclusion:

This study demonstrates that DIs correlate with the described neoplastic progression of L-SA, TA and L-SA compared with NCT and suggests that L-SA may be involved in a chromosome instability pathway of neoplastic progression.

Colon cancer remains a deadly disease, with a significant burden of illness to patients and healthcare systems. While most precursor lesions will not necessarily produce cancers, they vary in histology and potential for neoplastic progression. Aneuploidy or abnormal chromosomal content of a cell is considered a marker for chromosomal instability and neoplastic progression. However, conventional methods of assessment can be laborious, costly and may even underestimate its malignant potential if the lesion is focal, small and surrounded by normal stromal cells in the sampled tissue. We used a nuclear stain to detect and quantify aneuploidy on conventionally prepared colonic precancerous histological slides and in particular assessed serrated and hyperplastic polyps of the left colon. When compared with normal tissues, we determined that there was aneuploidy in these lesions, which supports the underappreciated assumption that these lesions manifest chromosomal instability.

Polyp Detection Rate as a Surrogate for Adenoma and Sessile Serrated Adenoma/Polyp Detection Rates

Introduction

Quality measures for colonoscopy such as adenoma detection rate (ADR) have been proposed to be surveilled for ensuring minimum standards. However, its direct measurement is time consuming and often neglected. Extrapolating ADR and other quality measures from polyp detection rate (PDR) can be a pragmatic alternative.

Objective

To determine quotients for estimating ADR and sessile serrated adenoma/polyp detection rate (SSA/P-DR) from PDR in an Australian cohort.

Methods

Consecutive adult patient colonoscopies during a 1-year period were retrospectively assessed in a single Australian tertiary endoscopy center. Adenoma detection quotient (ADQ) and SSA/P detection quotient (SSA/P-DQ) were defined as the division of ADR and SSA/P-DR by PDR, respectively. The primary outcome was the number of procedures to achieve a stable cumulative ADQ and SSA/P-DQ. Secondary outcomes included evaluation of ADQ and SSA/P-DQ in different subsets.

Results

In total, 2,657 colonoscopies were performed by 15 endoscopists in 2016. The ADR, SSA/P-DR, and PDR found were 32.2, 6.7, and 47.3%, respectively. The ADQ and SSA/P-DQ values found were 0.68 and 0.14, respectively. After approximately 500 procedures, both ADQ and SSA/P-DQ became stable. Interclass correlation coefficient (ICC) for the prediction of ADR from ADQ was excellent for all endoscopists that performed >177 procedures in that year (ICC 0.84).

Conclusions

ADQ and SSA/P-DQ values were consistent when over 500 procedures were analyzed. ADQ had an excellent correlation with ADR when >177 procedures per endoscopist were evaluated.