Joseph C. Anderson

Differences in Detection Rates of Adenomas and Serrated Polyps in Screening Versus Surveillance Colonoscopies, Based on the New Hampshire Colonoscopy Registry

BACKGROUND & AIMSnThe adenoma detection rate (ADR) is an important quality indicator originally developed forxa0screening colonoscopies. However, it is unclear whether the ADR should be calculated using data from screening and surveillance examinations. The recommended benchmark ADR for screening examinations is 20% (15% for women and 25% for men ≥50 y). There are few data available to compare ADRs from surveillance vs screening colonoscopies. We used a population-based registry to compare ADRs from screening vs surveillance colonoscopies. The serrated polyp detection rate (SDR), a potential new quality indicator, also was examined.nnnMETHODSnBy using data from the statewide New Hampshire Colonoscopy Registry, we excluded incomplete and diagnostic colonoscopies, and those performed in patients with inflammatory bowel disease, familial syndromes, or poor bowel preparation. We calculated the ADRxa0and SDR (number of colonoscopies with at least 1 adenoma or serrated polyp detected, respectively, divided by the number of colonoscopies) from 9100 colonoscopies. The ADRxa0and SDR were compared by colonoscopy indication (screening, surveillance), age at colonoscopy (50-64 y, ≥65 y), and sex.nnnRESULTSnThe ADR was significantly higher in surveillance colonoscopies (37%) than screening colonoscopies (25%; P < .001). This difference was observed for both sexes and age groups. There was a smaller difference in the SDR of screening (8%) vs surveillance colonoscopies (10%; P < .001).nnnCONCLUSIONSnIn a population-based study, we found that addition of data from surveillance colonoscopies increased the ADR but had a smaller effect on the SDR. These findings indicate that when calculating ADR as a quality measure, endoscopists should use screening, rather than surveillance colonoscopy, data.

Impact of fair bowel preparation quality on adenoma and serrated polyp detection: data from the New Hampshire Colonoscopy Registry by using a standardized preparation-quality rating

BACKGROUNDnThe effect of colon preparation quality on adenoma detection rates (ADRs) is unclear, partly because of lack of uniform colon preparation ratings in prior studies. The New Hampshire Colonoscopy Registry collects detailed data from colonoscopies statewide, by using a uniform preparation quality scale after the endoscopist has cleaned the mucosa.nnnOBJECTIVEnTo compare the overall and proximal ADR and serrated polyp detection rates (SDR) in colonoscopies with differing levels of colon preparation quality.nnnDESIGNnCross-sectional.nnnSETTINGnNew Hampshire statewide registry.nnnPATIENTSnPatients undergoing colonoscopy.nnnINTERVENTIONSnWe examined colon preparation quality for 13,022 colonoscopies, graded by using specific descriptions provided to endoscopists. ADR and SDR are the number of colonoscopies with at least 1 adenoma or serrated polyp (excluding those in the rectum and/or sigmoid colon) detected divided by the total number of colonoscopies, for the preparation categories: optimal (excellent and/or good), fair, and poor.nnnMAIN OUTCOME MEASUREMENTSnOverall/proximal ADR/SDR.nnnRESULTSnThe overall detection rates in examinations with fair colon preparation quality (SDR 8.9%; 95% confidence interval [CI], 7.4-10.7, ADR 27.1%; 95% CI, 24.6-30.0) were similar to rates observed in colonoscopies with optimal preparation quality (SDR 8.8%; 95% CI, 8.3-9.4, ADR 26.3%; 95% CI, 25.6-27.2). This finding also was observed for rates in the proximal colon. A logistic regression model (including withdrawal time) found that proximal ADR was statistically lower in the poor preparation category (odds ratio 0.45; 95% CI, 0.24-0.84; Pxa0< .01) than in adequately prepared colons.nnnLIMITATIONSnHomogeneous population.nnnCONCLUSIONnIn our sample, there was no significant difference in overall or proximal ADR or SDR between colonoscopies with fair versus optimal colon preparation quality. Poor colon preparation quality may reduce the proximal ADR.

Cap-assisted colonoscopy and detection of Adenomatous Polyps (CAP) study: a randomized trial

BACKGROUND AND STUDY AIMnCap-assisted colonoscopy has improved adenoma detection in some but not other studies. Most previous studies have been limited by small sample sizes and few participating endoscopists. The aim of the current study was to evaluate whether cap-assisted colonoscopy improves adenoma detection in a two-center, multi-endoscopist, randomized trial.nnnPATIENTS AND METHODSnConsecutive patients who presented for an elective colonoscopy were randomized to cap-assisted colonoscopy (4-mm cap) or standard colonoscopy performed by one of 10 experienced endoscopists. Primary outcome measures were mean number of adenomas per patient and adenoma detection rate (ADR). Secondary outcomes included procedural measures and endoscopist variation; a logistic regression model was employed to examine predictors of increased detection with cap use.nnnRESULTSnA total of 1113 patients (64u200a% male, mean age 62 years) were randomized to cap-assisted (nu200a=u200a561) or standard (nu200a=u200a552) colonoscopy. The mean number of adenomas detected per patient in the cap-assisted and standard groups was similar (0.89 vs. 0.82; Pu200a=u200a0.432), as was the ADR (42u200a% vs. 40u200a%; Pu200a=u200a0.452). Cap-assisted colonoscopy achieved a faster cecal intubation time (4.9 vs. 5.8 minutes; Pu200a<u200a0.001), a similar cecal intubation rate (99u200a% vs. 98u200a%; Pu200a=u200a0.326), and a higher terminal ileum intubation rate (93u200a% vs. 89u200a%; Pu200a<u200a0.028). Cap-assisted colonoscopy resulted in a 20u200a% increase in ADR for some endoscopists and in a 15u200a% decrease for others. Individual preference for the cap was an independent predictor of increased adenoma detection in adjusted analysis (Pu200a<u200a0.001), whereas baseline low adenoma detection was not.nnnCONCLUSIONnAlthough the efficiency of cecal and terminal ileum intubation was slightly improved by cap-assisted colonoscopy, adenoma detection was not. Cap-assisted colonoscopy may be beneficial for selected endoscopists.nnnTRIAL REGISTRATIONnclinicalTrials.gov (NCT01935180).

Total Body Weight Loss of ≥10 % Is Associated with Improved Hepatic Fibrosis in Patients with Nonalcoholic Steatohepatitis

BackgroundGiven the rising epidemics of obesity and metabolic syndrome, nonalcoholic steatohepatitis (NASH) is now the most common cause of liver disease in the developed world. Effective treatment for NASH, either to reverse or prevent the progression of hepatic fibrosis, is currently lacking.AimTo define the predictors associated with improved hepatic fibrosis in NASH patients undergoing serial liver biopsies at prolonged biopsy interval.MethodsThis is a cohort study of 45 NASH patients undergoing serial liver biopsies for clinical monitoring in a tertiary care setting. Biopsies were scored using the NASH Clinical Research Network guidelines. Fibrosis regression was defined as improvement in fibrosis score ≥1 stage. Univariate analysis utilized Fisher’s exact or Student’s t test. Multivariate regression models determined independent predictors for regression of fibrosis.ResultsForty-five NASH patients with biopsies collected at a mean interval of 4.6xa0years (±1.4) were included. The mean initial fibrosis stage was 1.96, two patients had cirrhosis and 12 patients (26.7xa0%) underwent bariatric surgery. There was a significantly higher rate of fibrosis regression among patients who lost ≥10xa0% total body weight (TBW) (63.2 vs. 9.1xa0%; pxa0=xa00.001) and who underwent bariatric surgery (47.4 vs. 4.5xa0%; pxa0=xa00.003). Factors such as age, gender, glucose intolerance, elevated ferritin, and A1AT heterozygosity did not influence fibrosis regression. On multivariate analysis, only weight loss of ≥10xa0% TBW predicted fibrosis regression [OR 8.14 (CI 1.08–61.17)].ConclusionResults indicate that regression of fibrosis in NASH is possible, even in advanced stages. Weight loss of ≥10xa0% TBW predicts fibrosis regression.

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

BACKGROUND AND AIMSnSimilar to achieving adenoma detection rate (ADR) benchmarks to prevent colorectal cancer (CRC), achieving adequate serrated polyp detection rates (SDRs) 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 (nxa0= 77 practicing at 28 centers) into high performers and low performers, based on ADR, to provide data for corresponding target SDR benchmarks.nnnMETHODSnBy using colonoscopies in adults agedxa0≥50 years (4/09-12/14), we stratified endoscopists by high and low ADRs (<15%, 15%-<25%, 25%-<35%,xa0≥35%) to determine corresponding SDRs by using 2 SDR measures, for screening and surveillance colonoscopies separately: (1) Clinically significant SDR (CSSDR), meaning colonoscopies with any sessile serrated adenoma/polyp (SSA/P), traditional serrated adenoma (TSA), or hyperplastic polyp (HP) >1 cm anywhere in the colon or HP >5xa0mm in the proximal colon only divided by the total number of screening and surveillance colonoscopies, respectively. (2) Proximal SDR (PSDR) meaning colonoscopies with any serrated polyp (SSA/P, HP, TSA) of any size proximal to the sigmoid colon divided by the total number of screening and surveillance colonoscopies, respectively.nnnRESULTSnA 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 (Pxa0= .69) and ADR/PSDR (Pxa0= .79) and a strong positive correlation (Pxa0= .82) for CSSDR/PSDR (Pxa0< .0001 for all) was observed. For ADRxa0≥25%, endoscopists median (interquartile range) screening CSSDR was 6.8% (4.3%-8.6%) and PSDR was 10.8% (8.6%-16.1%).nnnCONCLUSIONSnDerived from ADR, the primary colonoscopy quality indicator, our results suggest potential SDR benchmarks (CSSDRxa0= 7% and PSDRxa0= 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 Shorter Colonoscopy Surveillance Intervals for Patients With Low-Risk Colorectal Adenomas and Effects on Outcome

BACKGROUND & AIMSnEndoscopists do not routinely follow guidelines to survey individuals with low-risk adenomas (LRAs; 1-2 small tubular adenomas, < 1 cm) every 5-10 years for colorectal cancer; many recommend shorter surveillance intervals for these individuals. We aimed to identify the reasons that endoscopists recommend shorter surveillance intervals for some individuals with LRAs and determine whether timing affects outcomes at follow-up examinations.nnnMETHODSnWe collected data from 1560 individuals (45-75 years old) who participated in a prospective chemoprevention trial (of vitamin D and calcium) from 2004 through 2008. Participants in the trial had at least 1 adenoma, detected at their index colonoscopy, and were recommended to receive follow-up colonoscopy examinations at 3 or 5 years after adenoma identification, as recommended by the endoscopist. For this analysis we collected data from only participants with LRAs. These data included characteristics of participants and endoscopists and findings from index and follow-up colonoscopies. Primary endpoints were frequency of recommending shorter (3-year) vs longer (5-year) surveillance intervals, factors associated with these recommendations, and effect on outcome, determined at the follow-up colonoscopy.nnnRESULTSnA 3-year surveillance interval was recommended for 594 of the subjects (38.1%). Factors most significantly associated with recommendation of 3-year vs a 5-year surveillance interval included African American race (relative risk [RR] to white, 1.41; 95% confidence interval [CI], 1.14-1.75), Asian/Pacific Islander ethnicity (RR to white, 1.7; 95% CI, 1.22-2.43), detection of 2 adenomas at the index examination (RR vs 1 adenoma, 1.47; 95% CI, 1.27-1.71), more than 3 serrated polyps at the index examination (RR=2.16, 95% CI, 1.59-2.93), or index examination with fair or poor quality bowel preparation (RR vs excellent quality, 2.16; 95% CI, 1.66-2.83). Other factors that had a significant association with recommendation for a 3-year surveillance interval included family history of colorectal cancer and detection of 1-2 serrated polyps at the index examination. In comparisons of outcomes, we found no significant differences between the 3-year vs 5-year recommendation groups in proportions of subjects found to have 1 or more adenomas (38.8% vs 41.7% respectively; Pxa0=xa0.27), advanced adenomas (7.7% vs 8.2%; Pxa0=xa0.73) or clinically significant serrated polyps (10.0% vs 10.3%; Pxa0= .82) at the follow-up colonoscopy.nnnCONCLUSIONSnPossibly influenced by patients family history, race, quality of bowel preparation, or number or size of polyps, endoscopists frequently recommend 3-year surveillance intervals instead of guideline-recommended intervals of 5 years or longer for individuals with LRAs. However, at the follow-up colonoscopy, similar proportions of participants have 1 or more adenomas, advanced adenomas, or serrated polyps. These findings support the current guideline recommendations of performing follow-up examinations of individuals with LRAs at least 5 years after the index colonoscopy.

Pathogenesis and Management of Serrated Polyps: Current Status and Future Directions

Hyperplastic or serrated polyps were once believed to have little to no clinical significance. A subset of these polyps are now considered to be precursors to colorectal cancers (CRC) in the serrated pathway that may account for at least 15% of all tumors. The serrated pathway is distinct from the two other CRC pathways and involves an epigenetic hypermethylation mechanism of CpG islands within promoter regions of tumor suppressor genes. This process results in the formation of CpG island methylator phenotype tumors. Serrated polyps are divided into hyperplastic polyps, sessile serrated adenomas/polyps (SSA/Ps), and traditional serrated adenomas (TSAs). The SSA/P and the TSA have the potential for dysplasia and subsequent malignant transformation. The SSA/Ps are more common and are more likely to be flat than TSAs. Their flat morphology may make them difficult to detect and thus explain the variation in detection rates among endoscopists. Challenges for endoscopists also include the difficulty in pathological interpretation as well surveillance of these lesions. Furthermore, serrated polyps may be inadequately resected by endoscopists. Thus, it is not surprising that the serrated pathway has been linked with interval cancers. This review will provide the physician or clinician with the knowledge to manage patients with serrated polyps.

Update on Colon Cancer Screening: Recent Advances and Observations in Colorectal Cancer Screening

There have been many recent advances and observations regarding colorectal cancer (CRC) screening. New CRC surveillance guidelines have been published to help endoscopists with the management of important clinical issues such as serrated polyps. There have been several important large studies examining the impact of endoscopic process measures such as bowel prep, withdrawal time, and adenoma detection rate on CRC screening. In addition, there have been technical advances in CT colonography including the development of exams that do not require a bowel preparation. Other new technology such as colon capsule endoscopy may aid endoscopists in the challenge of completing the evaluation of the colon in those patients with an incomplete colonoscopy. Finally, there have been large studies which examine the performance characteristics of the so-called non-invasive CRC screening tests such as fecal immunochemical test (FIT) and fecal DNA.

Serrated Polyps: Clinical Implications and Future Directions

Serrated polyps were once thought to have no clinical implications with regards to the development of colorectal cancer (CRC). Over the past several years, published data have enabled clinicians to develop a better understanding of these lesions. The serrated pathway associated with these lesions involves an epigenetic mechanism characterized by abnormal hypermethylation of CpG islands located in the promoter regions of tumor suppressor genes. It is often associated with BRAF mutations and may account for 15–35xa0% of all CRC. This pathway may also play a major role in proximal neoplasia and missed cancer. There are three distinct subtypes of serrated neoplasia; hyperplastic (70xa0% of all serrated polyps), sessile serrated adenoma/polyp (SSA/P) (25xa0%) and traditional serrated adenoma (<2xa0%). The last two forms are considered to be precursors for CRC. SSA/P are associated with synchronous CRC especially if the polyps are large (≥1xa0cm), multiple, or if they are in the proximal colon. Lesions containing serrated neoplasia are usually flat or sessile, may be large, and occasionally have a mucous cap. Serrated lesions provide many challenges for the clinician and may be difficult to detect and completely remove. Furthermore, pathologists may misclassify SSA/P as HP. For the first time, the Multi-Society Task Force guidelines for colorectal polyp surveillance have included the management of serrated lesions in their published recommendations. In addition, an expert panel has also recently issued recommendations regarding serrated neoplasia. In this article, we provide the reader with a summary as well as the latest developments regarding serrated colonic lesions.

Water-Aided Colonoscopy

The successful intubation of the cecum during screening or surveillance colonoscopy is vital to ensure complete mucosal inspection of the colon on withdrawal. Even when performed by an experienced endoscopist, colonoscope insertion can sometimes be challenging. Water-aided colonoscopy can be used to assist the endoscopist in navigating colons with anatomies that may be challenging owing to severe angulation or redundancy. Water-assisted colonoscopy involves the infusion of water without air and subsequent suctioning during insertion (exchange) or withdrawal (immersion or infusion). This review discusses the technique, effectiveness, safety of water-assisted colonoscopy as well as the application in sedationless endscopy.