Adenoma detection in patients undergoing a comprehensive colonoscopy screening

The Efficacy of Real-time Computer-aided Detection of Colonic Neoplasia in Community Practice: A Pragmatic Randomized Controlled Trial

BACKGROUND & AIMS

The use of computer-aided detection (CADe) has increased the adenoma detection rates (ADRs) during colorectal cancer (CRC) screening/surveillance in randomized controlled trials (RCTs) but has not shown benefit in real-world implementation studies. We performed a single-center pragmatic RCT to evaluate the impact of real-time CADe on ADRs in colonoscopy performed by community gastroenterologists.

METHODS

We enrolled 1100 patients undergoing colonoscopy for CRC screening, surveillance, positive fecal-immunohistochemical tests, and diagnostic indications at one community-based center from September 2022 to March 2023. Patients were randomly assigned (1:1) to traditional colonoscopy or real-time CADe. Blinded pathologists analyzed histopathologic findings. The primary outcome was ADR (the percentage of patients with at least 1 histologically proven adenoma or carcinoma). Secondary outcomes were adenomas detected per colonoscopy (APC), sessile-serrated lesion detection rate, and non-neoplastic resection rate.

RESULTS

The median age was 55.5 years (interquartile range, 50-62 years), 61% were female, 72.7% were of Hispanic ethnicity, and 9.1% had inadequate bowel preparation. The ADR for the CADe group was significantly higher than the traditional colonoscopy group (42.5% vs 34.4%; P = .005). The mean APC was significantly higher in the CADe group compared with the traditional colonoscopy group (0.89 ± 1.46 vs 0.60 ± 1.12; P < .001). The improvement in adenoma detection was driven by increased detection of <5 mm adenomas. CADe had a higher sessile-serrated lesion detection rate than traditional colonoscopy (4.7% vs 2.0%; P = .01). The improvement in ADR with CADe was significantly higher in the first half of the study (47.2% vs 33.7%; P = .002) compared with the second half (38.7% vs 34.9%; P = .33).

CONCLUSIONS

In a single-center pragmatic RCT, real-time CADe modestly improved ADR and APC in average-detector community endoscopists. (ClinicalTrials.gov number, NCT05963724).

A Soft Sensor for Bleeding Detection in Colonoscopies

Colonoscopies allow surgeons to detect common diseases i.e. colorectal cancer, ulcers and other ailments. However, there is a risk of bleeding in the lower gastrointestinal (GI) tract while maneuvering endoscopes. This may be due to perforations, hemorrhaging, polyps, diverticuli or post-biopsy complications. Thus, it is essential for the surgeon to be able to detect bleeding at the site and evaluate the severity of blood leakage. This paper presents a soft sensor that can detect the presence of blood at the bleeding site during colonoscopies. The sensor consists of optical waveguides that interface with a microfluidic channel. Blood flow causes absorption and scattering of incident light that can be picked up by the optical sensing apparatus via light transmission through the waveguide. The surgeon can be alerted when bleeding occurs through a graphical user interface. The device is compact and measures only 1 mm thick. This allows the sensor to be circumferentially mounted onto a colonoscope at different locations. The sensor is able to record the presence of blood as an optical loss, rapidly detect the presence of blood in under 100 milliseconds as it enters the microchannel, and differentiate between gastric fluid and blood through changes in measured optical loss.

Adenoma Detection Rate in Colonoscopic Screening with Ketamine-based Sedation: A Prospective Observational Study

Objective:

This study aimed to determine the relationship between one of the most commonly used anesthesia techniques, ketaminebased sedation, on the value of adenoma detection rate (ADR) during colonoscopy screening.

Methods:

This prospective, observational study included 140 patients, who underwent a standard colonoscopy preparation before the procedure. Sedation regimens included ketamine at 0.5 mg/kg and propofol at 0.5 mg/kg. Additional doses of propofol were administered at 0.5 mg/kg to maintain the Ramsey Sedation scale. Baseline characteristics, ADR, bowel preparation quality according to the Chicago bowel preparation (CHBP) scale, cecal intubation, colonoscopy removal, and complications were analyzed.

Results:

The mean age of patients was 55.76 years; 40 (28.6%) were males and 100 (71.4%) were females. The ADR was 43.57%, wherein 15.71% in males and 27.86% in females. There were 43.6% adenomas, 17.9% biopsies, and 22.9% polypectomies. The largest location of adenomas/polyps were in the rectum and sigmoid and ascending colon (p=0.11), a biopsy of the sigmoid colon and ileum (p<0.05), polypectomy of the rectum and sigmoid and ascending colon (p<0.05). The cecal intubation was 93.6% with a withdrawal time that is >6 min in most patients (80%) (p<0.05). The CHBP scale showed good bowel preparation (p<0.05) without complications.

Conclusions:

Ketamine-based sedation is in good overall correlation with ADR. Therefore, the sedation technique should be included for ADR assessment in the future.

Prevalence and Clinical Features of Sessile Serrated Polyps: A Systematic Review

BACKGROUND & AIMS

Sessile serrated polyps (SSPs) could account for a substantial proportion of colorectal cancers. We aimed to increase clarity on SSP prevalence and clinical features.

METHODS

We performed a systematic review of MEDLINE, Web of Science, Embase, and Cochrane databases for original studies published in English since 2000. We included studies of different populations (United States general or similar), interventions (colonoscopy, autopsy), comparisons (world regions, alternative polyp definitions, adenoma), outcomes (prevalence, clinical features), and study designs (cross-sectional). Random-effects regression was used for meta-analysis where possible.

RESULTS

We identified 74 relevant colonoscopy studies. SSP prevalence varied by world region, from 2.6% in Asia (95% confidence interval [CI], 0-5.9) to 10.5% in Australia (95% CI, 2.8-18.2). Prevalence values did not differ significantly between the United States and Europe (P = .51); the pooled prevalence was 4.6% (95% CI, 3.4-5.8), and SSPs accounted for 9.4% of polyps with malignant potential (95% CI, 6.6-12.3). The mean prevalence was higher when assessed through high-performance examinations (9.1%; 95% CI, 4.0-14.2; P = .04) and with an alternative definition of clinically relevant serrated polyps (12.3%; 95% CI, 9.3-15.4; P < .001). Increases in prevalence with age were not statistically significant, and prevalence did not differ significantly by sex. Compared with adenomas, a higher proportion of SSPs were solitary (69.0%; 95% CI, 45.9-92.1; P = .08), with diameters of 10 mm or more (19.3%; 95% CI, 12.4-26.2; P = .13) and were proximal (71.5%; 95% CI, 63.5-79.5; P = .008). The mean ages for detection of SSP without dysplasia, with any or low-grade dysplasia, and with high-grade dysplasia were 60.8 years, 65.6 years, and 70.2 years, respectively. The range for proportions of SSPs with dysplasia was 3.7%-42.9% across studies, possibly reflecting different study populations.

CONCLUSIONS

In a systematic review, we found that SSPs are relatively uncommon compared with adenoma. More research is needed on appropriate diagnostic criteria, variations in detection, and long-term risk.

Detection Measures for Colonoscopy: Considerations On the Adenoma Detection Rate, Recommended Detection Thresholds, Withdrawal Times, and Potential Updates to Measures

The adenoma detection rate (ADR) was first proposed by the US Multi-Society Task Force on Colorectal Cancer in 2002 and, subsequently, has been validated as a strong predictor of colorectal cancer risk after colonoscopy. ADR is now widely considered the most important quality measure in colonoscopy. ADR is a surrogate for missed lesions and for cancer incidence after colonoscopy. ADR has weaknesses, and multiple other detection targets have been evaluated as alternatives. This review discusses the history of ADR, the strength and weaknesses of ADR, and proposed alternatives to ADR. Of the alternatives, adenomas per colonoscopy has the most advantages with limited disadvantages relative to ADR and has some potential to eventually replace ADR.

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

In addition to the adenoma to carcinoma sequence, colorectal carcinogenesis can occur via the serrated pathway. Studies have focused on clarification of categories and molecular features of serrated polyps, as well as endoscopic detection and risk assessment. Guidelines from the World Health Organization propose assigning serrated polyps to categories of hyperplastic polyps, traditional serrated adenomas, and sessile serrated lesions (SSLs). Traditional serrated adenomas and SSLs are precursors to colorectal cancer. The serrated pathway is characterized by mutations in RAS and RAF, disruptions to the Wnt signaling pathway, and widespread methylation of CpG islands. Epidemiology studies of serrated polyps have been hampered by inconsistencies in terminology and reporting, but the prevalence of serrated class polyps is 20%-40% in average-risk individuals; most serrated polyps detected are hyperplastic. SSLs, the most common premalignant serrated subtype, and are found in up to 15% of average-risk patients by high-detecting endoscopists. Variations in rate of endoscopic detection of serrated polyps indicate the need for careful examination, with adequate bowel preparation and sufficient withdrawal times. Risk factors for SSLs include white race, family history of colorectal cancer, smoking, and alcohol intake. Patients with serrated polyps, particularly SSLs and traditional serrated adenomas, have an increased risk of synchronous and metachronous advanced neoplasia. Surveillance guidelines vary among countries, but SSLs and proximal hyperplastic polyps require special attention in assignment of surveillance interval-especially in light of concerns regarding incomplete detection and resection.

Polyp detection rate: does length matter?

INTRODUCTION

Polyp detection rate is a surrogate marker for adenoma detection rate and therefore a surrogate marker of quality colonoscopy. To our knowledge, this is the first study that compares distance from the monitor to the endoscopist on polyp detection rate.

METHODS

This was a retrospective study comparing polyp detection rate across two different endoscopy room set-ups. All colonoscopies performed between December 2013 and November 2014 were retrieved. The difference in the room set-up was the distance from the endoscopist to the endoscopy monitor. Room A had a distance of 219 cm and Room B had 147 cm. We used two identical rooms, C and D, as a control arm with a distance of 190 cm between the endoscopist and the monitor.

RESULTS

There were significant differences in polyp detection rates between Room A and Room B in the bowel cancer screening lists. For these lists, the room with the closest distance from the endoscopist to the monitor (147 cm) had a statistically significant higher polyp detection rate than the room that had a further monitor to endoscopist distance of 219 cm (p<0.0006) and a trend towards a higher polyp detection rate compared with the room where the distance between the monitor and the endoscopist was 190 cm (p=0.08). This effect was not noticed across the service lists.

CONCLUSIONS

This study has suggested that the distance from the endoscopist to the monitor can affect polyp detection rate. It appears that for bowel cancer screening lists, the further the endoscopist from the monitor the lower their polyp detection rate.

Virtual chromoendoscopy for the real-time assessment of colorectal polyps in vivo: a systematic review and economic evaluation

BACKGROUND

Current clinical practice is to remove a colorectal polyp detected during colonoscopy and determine whether it is an adenoma or hyperplastic by histopathology. Identifying adenomas is important because they may eventually become cancerous if untreated, whereas hyperplastic polyps do not usually develop into cancer, and a surveillance interval is set based on the number and size of adenomas found. Virtual chromoendoscopy (VCE) (an electronic endoscopic imaging technique) could be used by the endoscopist under strictly controlled conditions for real-time optical diagnosis of diminutive (≤ 5 mm) colorectal polyps to replace histopathological diagnosis.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of the VCE technologies narrow-band imaging (NBI), flexible spectral imaging colour enhancement (FICE) and i-scan for the characterisation and management of diminutive (≤ 5 mm) colorectal polyps using high-definition (HD) systems without magnification.

DESIGN

Systematic review and economic analysis.

PARTICIPANTS

People undergoing colonoscopy for screening or surveillance or to investigate symptoms suggestive of colorectal cancer.

INTERVENTIONS

NBI, FICE and i-scan.

MAIN OUTCOME MEASURES

Diagnostic accuracy, recommended surveillance intervals, health-related quality of life (HRQoL), adverse effects, incidence of colorectal cancer, mortality and cost-effectiveness of VCE compared with histopathology.

DATA SOURCES

Electronic bibliographic databases including MEDLINE, EMBASE, The Cochrane Library and Database of Abstracts of Reviews of Effects were searched for published English-language studies from inception to June 2016. Bibliographies of related papers, systematic reviews and company information were screened and experts were contacted to identify additional evidence.

REVIEW METHODS

Systematic reviews of test accuracy and economic evaluations were undertaken in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Meta-analyses were conducted, where possible, to inform the independent economic model. A cost-utility decision-analytic model was developed to estimate the cost-effectiveness of VCE compared with histopathology. The model used a decision tree for patients undergoing endoscopy, combined with estimates of long-term outcomes (e.g. incidence of colorectal cancer and subsequent morbidity and mortality) derived from University of Sheffield School of Health and Related Research's bowel cancer screening model. The model took a NHS perspective, with costs and benefits discounted at 3.5% over a lifetime horizon. There were limitations in the data on the distribution of adenomas across risk categories and recurrence rates post polypectomy.

RESULTS

Thirty test accuracy studies were included: 24 for NBI, five for i-scan and three for FICE (two studies assessed two interventions). Polyp assessments made with high confidence were associated with higher sensitivity and endoscopists experienced in VCE achieved better results than those without experience. Two economic evaluations were included. NBI, i-scan and FICE are cost-saving strategies compared with histopathology and the number of quality-adjusted life-years gained was similar for histopathology and VCE. The correct surveillance interval would be given to 95% of patients with NBI, 94% of patients with FICE and 97% of patients with i-scan.

LIMITATIONS

Limited evidence was available for i-scan and FICE and there was heterogeneity among the NBI studies. There is a lack of data on longer-term health outcomes of patients undergoing VCE for assessment of diminutive colorectal polyps.

CONCLUSIONS

VCE technologies, using HD systems without magnification, could potentially be used for the real-time assessment of diminutive colorectal polyps, if endoscopists have adequate experience and training.

FUTURE WORK

Future research priorities include head-to-head randomised controlled trials of all three VCE technologies; more research on the diagnostic accuracy of FICE and i-scan (when used without magnification); further studies evaluating the impact of endoscopist experience and training on outcomes; studies measuring adverse effects, HRQoL and anxiety; and longitudinal data on colorectal cancer incidence, HRQoL and mortality.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016037767.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Clinicopathological features of colorectal polyps in 2002 and 2012

BACKGROUND/AIMS

There are few comparative studies on the historical changes in the clinicopathologic characteristics of colorectal polyps in Korea. This retrospective study compared the clinicopathologic characteristics of colorectal polyps treated at our institution in 2002 and 2012.

METHODS

The medical records of 1,816 patients who underwent colonoscopy and were found to have colorectal polyps in 2002 (n = 597) or 2012 (n = 1,219) were reviewed retrospectively. Patient characteristics and polyp sizes, gross morphologies, locations, and pathologic results were analyzed and compared.

RESULTS

Mean age was older in the 2002 group than in the 2012 group (67.3 ± 11.1 years vs. 55.4 ± 10.8 years, p < 0.001). The 1,816 study subjects had a total of 3,723 colorectal polyps, with a mean of 2.05 polyps per patient. Mean polyp size was larger in the 2002 group than in the 2012 group (0.6 ± 0.4 cm vs. 0.4 ± 0.3 cm, p < 0.001). The most common histology was tubular adenoma and they were more common in the right colon in both study groups. Although the distribution of total adenoma was not significantly different between groups, the location of advanced adenoma differed significantly and was more common in the right colon in the 2012 group (30.4% vs. 63.2%, p = 0.01).

CONCLUSION

No significant change in total polyps and adenoma distribution was found between 2002 and 2012. However, advanced adenoma was more common in the right colon in 2012, which cautiously suggests a locational shift from the left to right colon. These findings indicate that right colon polyps require more attention.

Serrated polyps - a concealed but prevalent precursor of colorectal cancer

Serrated polyps have long been considered to lack malignant potential but accumulating data suggest that these lesions may cause up to one-third of all sporadic colorectal cancer. Serrated polyps are classified into three subtypes, including sessile serrated adenomas/polyps (SSA/Ps), traditional serrated adenomas (TSAs), and hyperplastic polyps (HPs). SSA/P and TSA harbour malignant potential but TSA represents only 1-2%, wheras SSA/P constitute up to 20% of all serrated lesions. HPs are most common (80%) of all serrated polyps but are considered to have a low potential of developing colorectal cancer. Due to their subtle appearence, detection and removal of serrated polyps pose a major challenge to endoscopists. Considering that precancerous serrated polyps are predominately located in the right colon could explain why interval cancers most frequently appear in the proximal colon and why colonoscopy is less protective against colon cancer in the proximal compared to the distal colon. Despite the significant impact on colorectal cancer incidence, the aetiology, incidence, prevalence, and natural history of serrated polyps is incompletely known. To effectively detect, remove, and follow-up serrated polyps, endoscopists and pathologists should be well-informed about serrated polyps. This review highlights colorectal serrated polyps in terms of biology, types, diagnosis, therapy, and follow-up.

British Society of Gastroenterology position statement on serrated polyps in the colon and rectum

Serrated polyps have been recognised in the last decade as important premalignant lesions accounting for between 15% and 30% of colorectal cancers. There is therefore a clinical need for guidance on how to manage these lesions; however, the evidence base is limited. A working group was commission by the British Society of Gastroenterology (BSG) Endoscopy section to review the available evidence and develop a position statement to provide clinical guidance until the evidence becomes available to support a formal guideline. The scope of the position statement was wide-ranging and included: evidence that serrated lesions have premalignant potential; detection and resection of serrated lesions; surveillance strategies after detection of serrated lesions; special situations-serrated polyposis syndrome (including surgery) and serrated lesions in colitis; education, audit and benchmarks and research questions. Statements on these issues were proposed where the evidence was deemed sufficient, and re-evaluated modified via a Delphi process until >80% agreement was reached. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool was used to assess the strength of evidence and strength of recommendation for finalised statements. Key recommendation: we suggest that until further evidence on the efficacy or otherwise of surveillance are published, patients with sessile serrated lesions (SSLs) that appear associated with a higher risk of future neoplasia or colorectal cancer (SSLs ≥10 mm or serrated lesions harbouring dysplasia including traditional serrated adenomas) should be offered a one-off colonoscopic surveillance examination at 3 years (weak recommendation, low quality evidence, 90% agreement).

The clinical impact of serrated colorectal polyps

Serrated polyps (SPs) of the colorectum pose a novel challenge to practicing gastroenterologists. Previously thought benign and unimportant, there is now compelling evidence that SPs are responsible for a significant percentage of incident colorectal cancer worldwide. In contrast to conventional adenomas, which tend to be slow growing and polypoid, SPs have unique features that undermine current screening and surveillance practices. For example, sessile serrated polyps (SSPs) are flat, predominately right-sided, and thought to have the potential for rapid growth. Moreover, SSPs are subject to wide variations in endoscopic detection and pathologic interpretation. Unfortunately, little is known about the natural history of SPs, and current guidelines are based largely on expert opinion. In this review, we outline the current taxonomy, epidemiology, and management of SPs with an emphasis on the clinical and public health impact of these lesions.

Clinicopathological characteristics of serrated polyps as precursors to colorectal cancer: Current status and management

Serrated polyps have long been thought to lack malignant potential in the human colorectum. However, identification of the serrated pathway to colorectal cancer based on molecular biology has improved our understanding of the pathogenesis of colorectal cancers. Accordingly, serrated polyps such as traditional serrated adenoma and sessile serrated adenoma/polyps (SSA/P) are now considered to be precursor lesions of the serrated pathway. Recently, serrated polyps were classified into three subtypes, consisting of hyperplastic polyp, SSA/P, and traditional serrated adenoma, according to the World Health Organization classification. It has been suggested that SSA/P in the proximal colon are a precursor lesion of pathogenesis of colorectal cancer and are characterized by BRAF mutation and a CpG island methylator phenotype with or without microsatellite instability. However, SSA/P is more challenging to detect by colonoscopy and is likely to account for some interval cancers, particularly in the proximal colon because it presents flat or sessile, isochroous appearance, and occasionally has a mucous cap. Furthermore, the possibility has been raised that pathologists misclassify SSA/P as hyperplastic polyp. It is important for gastroenterologists to recognize the endoscopic features of serrated polyps to facilitate their detection and removal and also to establish postpolypectomy surveillance guidelines. In this review, we discuss the recent classification of serrated polyps; the molecular characteristics of the serrated pathway; appropriate diagnostic methods using endoscopy, including a new image-enhanced endoscopic technique; and management of these lesions.

Comparative analysis of endoscopic and histopathological features of superficial elevated lesions resected by endoscopic mucosal resection in the distal and proximal colon

OBJECTIVE

to compare endoscopic and histopathologic features of superficial, elevated lesions with one or more centimeters in diameter, diagnosed by videocolonoscopy on the distal and proximal colon, and subjected to mucosal resection.

METHODS

we conducted a retrospective, cross-sectional, observational study involving 8,075 videocolonoscopies. From this total, we evaluated 166 mucosectomies in 145 patients with superficial, elevated lesions with a diameter equal to or greater than 1cm.

RESULTS

the lesion prevalence was lower in G1 than in G2 (34.9% vs. 65%). The mean age, gender distribution and size (1.9cm in G1 versus 2.0cm in G2, p=0.921) were similar. There was no difference of mucosal surfaces in relation to the location (p=0.575). Considering Intraepithelial neoplasias, both the low grade, high grade (including carcinomas) and hyperplasic ones showedd no difference (p=0.527), nor did the neoplastic lesions when divided into serrated and non-serrated (p=0.124). Excluding 13 hyperplastic lesions and two carcinomas, 124 (82.1%) were non-serrated and 27 (17.9%), serrated.

CONCLUSION

were found no significant differences between endoscopic and histopathological aspects of superficial, elevated lesions of 1cm or more in diameter in distal colon compared with the proximal, when resected by mucosectomy. Although not significant, there was a tendency of association between the location of the lesion and the presence of serrated features.

OBJETIVO

comparar aspectos endoscópicos e histopatológicos de lesões superficialmente elevadas, com um ou mais centímetros de diâmetro, diagnosticadas por videocolonoscopias e ressecadas por mucosectomias do cólon distal com as do cólon proximal.

MÉTODOS

estudo foi retrospectivo, transversal, observacional, envolvendo 8075 videocolonoscopias. Avaliou-se 166 mucosectomias em 145 pacientes com lesões superficialmente elevadas com diâmetro igual ou maior do que 1cm.

RESULTADOS

a prevalência de lesões foi menor no G1 do que no G2 (34,9% x 65%). A média de idade, a distribuição por sexo e o tamanho (1,9cm no G1 e 2cm no G2, p=0,921) foram semelhantes. Não houve diferenças das superfícies em relação à localização (p=0,575). Considerando neoplasia intraepitelial de baixo grau, neoplasia intraepitelial de alto grau (incluindo carcinomas) e hiperplásicas, não houve diferença (p=0,527), assim como quando foram divididas as lesões neoplásicas em serrilhadas e não serrilhadas (p=0,124). Excluindo-se 13 lesões hiperplásicas e duas com carcinomas, 124 (82,1%) foram não serrilhadas e 27 (17,9%) serrilhadas.

CONCLUSÃO

não foram observadas diferenças significativas entre os aspectos endoscópicos e os histopatológicos das lesões superficialmente elevadas, com 1cm ou mais de diâmetro, ressecadas por mucosectomia do cólon distal em relação ao proximal. Embora não significante, há tendência à associação entre a localização da lesão e a presença de características serrilhadas.

The impact of exclusion criteria on a physician's adenoma detection rate

BACKGROUND

The adenoma detection rate (ADR) is a validated and widely used measure of colonoscopy quality. There is uncertainty in the published literature as to which colonoscopy examinations should be excluded when measuring a physician's ADR.

OBJECTIVE

To examine the impact of varying the colonoscopy exclusion criteria on physician ADR.

DESIGN

We applied different exclusion criteria used in 30 previous studies to a dataset of endoscopy and pathology reports. Under each exclusion criterion, we calculated physician ADR.

SETTING

A private practice colonoscopy center affiliated with the University of Illinois College of Medicine.

PATIENTS

Data on 20,040 colonoscopy examinations performed by 11 gastroenterologists from July 2009 to May 2013 and associated pathology notes.

MAIN OUTCOME MEASUREMENTS

ADRs across all colonoscopy examinations, each physician's ADR, and ADR ranking.

RESULTS

There were 28 different exclusion criteria used when measuring the ADR. Each study used a different combination of these exclusion criteria. The proportion of all colonoscopy examinations in the dataset excluded under these combinations of exclusion criteria ranged from 0% to 92.2%. The mean ADR across all colonoscopy examinations was 39.1%. The change in mean ADR after applying the 28 exclusion criteria ranged from -5.5 to +3.0 percentage points. However, the exclusion criteria affected each physician's ADR relatively equally, and therefore physicians' rankings via the ADR were stable.

LIMITATIONS

ADR assessment was limited to a single private endoscopy center.

CONCLUSION

There is wide variation in the exclusion criteria used when measuring the ADR. Although these exclusion criteria can affect overall ADRs, the relative rankings of physicians by ADR were stable. A consensus definition of which exclusion criteria are applied when measuring ADR is needed.

Natural language processing as an alternative to manual reporting of colonoscopy quality metrics

BACKGROUND AND AIMS

The adenoma detection rate (ADR) is a quality metric tied to interval colon cancer occurrence. However, manual extraction of data to calculate and track the ADR in clinical practice is labor-intensive. To overcome this difficulty, we developed a natural language processing (NLP) method to identify adenomas and sessile serrated adenomas (SSAs) in patients undergoing their first screening colonoscopy. We compared the NLP-generated results with that of manual data extraction to test the accuracy of NLP and report on colonoscopy quality metrics using NLP.

METHODS

Identification of screening colonoscopies using NLP was compared with that using the manual method for 12,748 patients who underwent colonoscopies from July 2010 to February 2013. Also, identification of adenomas and SSAs using NLP was compared with that using the manual method with 2259 matched patient records. Colonoscopy ADRs using these methods were generated for each physician.

RESULTS

NLP correctly identified 91.3% of the screening examinations, whereas the manual method identified 87.8% of them. Both the manual method and NLP correctly identified examinations of patients with adenomas and SSAs in the matched records almost perfectly. Both NLP and the manual method produced comparable values for ADRs for each endoscopist and for the group as a whole.

CONCLUSIONS

NLP can correctly identify screening colonoscopies, accurately identify adenomas and SSAs in a pathology database, and provide real-time quality metrics for colonoscopy.

High rate of advanced colorectal polyps in a 10-year-long retrospective study in Qazvin, Iran

BACKGROUND

Polyps are common lesions in the gastrointestinal (GI) tract. Colon cancer is mostly a result of progression from polyps. The present study aimed to evaluate demographic, clinical, and histological characteristics of colorectal polyps in Iran, particularly neoplastic and advanced types.

MATERIALS AND METHODS

Over a period of 10 years, specimens of all colorectal polyps obtained from colonoscopy were studied. The variables subjected to statistical analysis were age, sex, and the chief clinical complaint of the patients who underwent colonoscopy, their motivation, and the site, size, and histological types of detected polyps. The level of significance was set at p value<0.05.

RESULTS

Data were obtained from a total of 352 patients. No difference was seen between male and female patients regarding histological types. Only in nine patients was screening the reason for colonoscopy. Almost two-thirds (66.2%) of the polyps were neoplastic. Familial polyposis syndrome and inflammatory bowel disease were seen in 4.3% and 3.0% of the patients with neoplastic polyps, respectively. Sites of polyps were the sigmoid, rectum, and descending colon in 40.1%, 34.5%, and 17% of the cases, respectively. The advanced type made up 58.8% of neoplastic polyps. Only 3.6% of the patients undergoing colonoscopy in the study period had biopsied polyps.

DISCUSSION

No difference was observed between male and female patients in terms of overall incidence of polyps, histological and anatomical profiles, and mean age distribution. Anatomical and histological profiles agreed with the studies performed in areas with a low risk of colon cancer. The findings show that colonoscopy was not performed when it was necessary. A meaningful increase in the number polyp biopsy cases and a corresponding decrease in polyp size in the last few years of the study can be associated with the presence of more GI specialist clinicians in hospital centers, and this holds out much hope for the further improvement of the situation in the future.

Detection rates of premalignant polyps during screening colonoscopy: time to revise quality standards?

BACKGROUND

Standards for the detection of adenomas during screening colonoscopy are widely used to measure examination quality. No such standards exist for sessile serrated adenomas (SSAs).

OBJECTIVE

To measure both the adenoma detection rate (ADR) and SSA detection rate (SSADR) during screening colonoscopy before and after quality improvement/financial incentive measures.

DESIGN

Retrospective determination of baseline ADR/SSADR by the endoscopist, followed by prospective collection of data after informing physicians of baseline detection rates.

SETTING

Tertiary cancer center with a large cancer screening program.

PATIENTS

A total of 2833 average-risk colorectal cancer screening patients 50 to 75 years of age undergoing initial colonoscopy.

DATA COLLECTION

Electronic medical records for indication and demographics, endoscopy report, and pathology report.

MAIN OUTCOME MEASUREMENTS

Detection rates of adenomas and SSAs by sex.

RESULTS

The overall ADR in male and female patients was 50.6% and 36.6%, respectively. The overall detection rate of advanced adenomas in male and female patients was 12.4% and 6.5%, respectively. The overall SSADR in male and female patients was 10.1% and 7.1%, respectively. In 108 patients (3.8% of entire group), SSAs were the only premalignant lesions found. Detection rates of both types of premalignant polyps improved over time but did not reach statistical significance.

LIMITATIONS

Single-center experience with limited sample size and small group of endoscopists.

CONCLUSION

ADRs far in excess of current standards are achievable. Cecal withdrawal time is associated with the ADR. Prevalence of SSA rivals that of advanced adenomas and is greater than current medical literature suggests. The combination of monitoring and financial incentives did not result in statistically significant improvement in ADRs.

Sessile serrated adenomas: an evidence-based guide to management

The concept of serrated colorectal neoplasia and a serrated pathway to colorectal cancer (CRC) is relatively new and continuing to evolve, but it has become highly relevant to gastroenterologists, pathologist, and oncologists alike. Sessile serrated adenomas (SSA) are now thought to be the major precursor lesion of serrated pathway cancers, which represent up to one-third of all sporadic CRC cases. However, despite their increasingly recognized importance, relatively little is known about the epidemiology and natural history of SSAs, and the molecular and epigenetic aspects are incompletely understood. Endoscopists must be aware of the unique features of SSAs so that the practice of colonoscopic screening for CRC can include optimized detection, removal, and appropriate surveillance of SSAs and other serrated precursor lesions. In this review, we discuss the history, epidemiology, and pathologic aspects of SSAs, as well as a recommended management approach and a discussion of uncertainties and opportunities for future research.

High-definition white-light (HDWL) colonoscopy and higher adenoma detection rate and the potential for paradoxical over surveillance

BACKGROUND

Patients undergoing high-definition white-light colonoscopy by a high adenoma detector may have a lower risk of interval adenoma detection on follow-up colonoscopy and may require less frequent follow-up but may paradoxically be assigned to more frequent surveillance when more adenomas are detected.

AIMS

To evaluate whether high-definition white-light colonoscopy (vs. standard-definition white-light colonoscopy) and endoscopist adenoma detection rate (ADR) at index colonoscopy are associated with increased likelihood of adenomas at follow-up.

METHODS

Longitudinal follow-up of prior cross-section cohort study of patients who underwent colonoscopy at baseline with at least one detected adenoma was included. Associations of type of white-light at index colonoscopy and the ADR of the endoscopist at index colonoscopy (high vs. low adenoma detector) were evaluated with various adenoma and polyp detection endpoints. Eighteen endoscopists were classified as high and low adenoma detectors based on the median ADR of 0.255.

RESULTS

There were no significant differences in subsequent interval adenoma or polyp detection endpoints with regard to whether baseline exam was performed with high-definition white-light or standard-definition white-light colonoscopy nor between high and low ADR after adjusting for multiple testing (P ≤ 0.0029 considered significant). Prior to multiple testing adjustment, there was a significantly lower detection rate of hyperplastic polyps in the left colon (24 vs. 35 %, OR: 0.56, P = 0.033) at follow-up colonoscopy when baseline exam was performed with high-definition white-light index colonoscopy.

CONCLUSIONS

The results of this study do not support adjusting colonoscopy surveillance guidelines based on type of colonoscopy performed or the endoscopist's ADR.

Follow-up intervals for precancerous colorectal conditions

Colorectal cancer screening is useful not only in detecting colorectal cancer at an early stage, but also in finding people with precancerous conditions. Proper interference in precancerous patients is good for reducing the occurrence of cancer. The precancerous conditions vary from patient to patient, so is the risk of malignant transformation. However, the lack of clear definition and classification for precancerous colorectal conditions in China makes standard treatment and follow-up management of these people difficult. This review summarizes basic definition and classification for precancerous colorectal conditions, clarifies different risks among people, and introduces the latest progress in follow-up intervals worldwide.