Polyp detection rate may predict adenoma detection rate: a meta-analysis

Overall Polyp Detection Rate as a Surrogate Measure for Screening Efficacy Independent of Histopathology: Evidence from National Endoscopy Database

Adenoma detection rate (ADR) is challenging to measure, given its dependency on pathology reporting. Polyp detection rate (PDR) (percentage of screening colonoscopies detecting a polyp) is a proposed alternative to overcome this issue. Overall PDR from all colonoscopies is a relatively novel concept, with no large-scale studies comparing overall PDR with screening-only PDR. The aim of the study was to compare PDR from screening, surveillance, and diagnostic indications with overall PDR and evaluate any correlation between individual endoscopist PDR by indication to determine if overall PDR can be a valuable surrogate for screening PDR. Our study analyzed a prospectively collected national endoscopy database maintained by the National Institute of Health from 2009 to 2014. Out of 354,505 colonoscopies performed between 2009-2014, 298,920 (n = 110,794 average-risk screening, n = 83,556 average-risk surveillance, n = 104,770 diagnostic) met inclusion criteria. The median screening PDR was 25.45 (IQR 13.15-39.60), comparable with the median overall PDR of 24.01 (IQR 11.46-35.86, p = 0.21). Median surveillance PDR was higher at 33.73 (IQR 16.92-47.01), and median diagnostic PDR was lower at 19.35 (IQR 9.66-29.17), compared with median overall PDR 24.01 (IQR 11.46-35.86; p < 0.01). The overall PDR showed excellent concordance with screening, surveillance, and diagnostic PDR (r > 0.85, p < 0.01, 2-tailed). The overall PDR is a reliable and pragmatic surrogate for screening PDR and can be measured in real time, irrespective of colonoscopy indication.

Lack of Effectiveness of Computer Aided Detection for Colorectal Neoplasia: A Systematic Review and Meta-Analysis of Nonrandomized Studies

BACKGROUND AND AIMS

Benefits of computer-aided detection (CADe) in detecting colorectal neoplasia were shown in many randomized trials in which endoscopists' behavior was strictly controlled. However, the effect of CADe on endoscopists' performance in less-controlled setting is unclear. This systematic review and meta-analyses were aimed at clarifying benefits and harms of using CADe in real-world colonoscopy.

METHODS

We searched MEDLINE, EMBASE, Cochrane, and Google Scholar from inception to August 20, 2023. We included nonrandomized studies that compared the effectiveness between CADe-assisted and standard colonoscopy. Two investigators independently extracted study data and quality. Pairwise meta-analysis was performed utilizing risk ratio for dichotomous variables and mean difference (MD) for continuous variables with a 95% confidence interval (CI).

RESULTS

Eight studies were included, comprising 9782 patients (4569 with CADe and 5213 without CADe). Regarding benefits, there was a difference in neither adenoma detection rate (44% vs 38%; risk ratio, 1.11; 95% CI, 0.97 to 1.28) nor mean adenomas per colonoscopy (0.93 vs 0.79; MD, 0.14; 95% CI, -0.04 to 0.32) between CADe-assisted and standard colonoscopy, respectively. Regarding harms, there was no difference in the mean non-neoplastic lesions per colonoscopy (8 studies included for analysis; 0.52 vs 0.47; MD, 0.14; 95% CI, -0.07 to 0.34) and withdrawal time (6 studies included for analysis; 14.3 vs 13.4 minutes; MD, 0.8 minutes; 95% CI, -0.18 to 1.90). There was a substantial heterogeneity, and all outcomes were graded with a very low certainty of evidence.

CONCLUSION

CADe in colonoscopies neither improves the detection of colorectal neoplasia nor increases burden of colonoscopy in real-world, nonrandomized studies, questioning the generalizability of the results of randomized trials.

Performance comparison between two computer-aided detection colonoscopy models by trainees using different false positive thresholds: a cross-sectional study in Thailand

BACKGROUND/AIMS

This study aims to compare polyp detection performance of "Deep-GI," a newly developed artificial intelligence (AI) model, to a previously validated AI model computer-aided polyp detection (CADe) using various false positive (FP) thresholds and determining the best threshold for each model.

METHODS

Colonoscopy videos were collected prospectively and reviewed by three expert endoscopists (gold standard), trainees, CADe (CAD EYE; Fujifilm Corp.), and Deep-GI. Polyp detection sensitivity (PDS), polyp miss rates (PMR), and false-positive alarm rates (FPR) were compared among the three groups using different FP thresholds for the duration of bounding boxes appearing on the screen.

RESULTS

In total, 170 colonoscopy videos were used in this study. Deep-GI showed the highest PDS (99.4% vs. 85.4% vs. 66.7%, p<0.01) and the lowest PMR (0.6% vs. 14.6% vs. 33.3%, p<0.01) when compared to CADe and trainees, respectively. Compared to CADe, Deep-GI demonstrated lower FPR at FP thresholds of ≥0.5 (12.1 vs. 22.4) and ≥1 second (4.4 vs. 6.8) (both p<0.05). However, when the threshold was raised to ≥1.5 seconds, the FPR became comparable (2 vs. 2.4, p=0.3), while the PMR increased from 2% to 10%.

CONCLUSION

Compared to CADe, Deep-GI demonstrated a higher PDS with significantly lower FPR at ≥0.5- and ≥1-second thresholds. At the ≥1.5-second threshold, both systems showed comparable FPR with increased PMR.

Clinical value of sigmoid colon water exchange colonoscopy: a prospective randomized clinical trial

This prospective randomized controlled trial investigated the clinical value of sigmoid colon water exchange (SWE) colonoscopy by comparing it with air insufflation (AI) colonoscopy in terms of the patient's pain score, insertion time, and screening quality. Consecutive patients who underwent colonoscopy without sedation were randomized into an AI group (n = 267) or an SWE group (n = 255). Patient characteristics, history of abdominal or pelvic surgery, maximum pain score, insertion time, cecal intubation rate, polyp detection rate, and the need for maneuvers were recorded. There was no significant between-group difference in insertion time, cecal intubation rate, assisted maneuvers (abdominal pressure, changing patients' position), or polyp detection rate (P > 0.05). The mean maximum pain score was significantly lower in the SWE group than in the AI group. (3.57 ± 2.01 vs. 4.69 ± 1.83, P < 0.001). For patients with a history of abdominal or pelvic surgery and those who were overweight (body mass index > 24), the maximum pain scores were lower in the SWE group than in the AI group (3.67 ± 1.95 vs. 4.88 ± 1.80, P < 0.001; 3.40 ± 1.96 vs. 4.79 ± 1.97, P < 0.001, respectively). SWE colonoscopy can significantly reduce abdominal pain with non-inferior screening quality and does not increase insertion time.Trial registration number: ChiCTR2200059057 (date April 23, 2022).

Population-Based Prevalence of Gastrointestinal Abnormalities at Colon Capsule Endoscopy

BACKGROUND & AIMS

The population prevalence of gastrointestinal (GI) disease is unclear and difficult to assess in an asymptomatic population. The aim of this study was to determine prevalence of GI lesions in a largely asymptomatic population undergoing colon capsule endoscopy (CCE).

METHODS

Participants aged between 50-75 years were retrieved from the Rotterdam Study, a longitudinal epidemiological study, between 2017-2019. Participants received CCE with bowel preparation. Abnormalities defined as clinically relevant were Barrett segment >3cm, severe ulceration, polyp >10 mm or ≥3 polyps in small bowel (SB) or colon, and cancer.

RESULTS

Of 2800 invited subjects, 462 (16.5%) participants (mean age 66.8 years, female 53.5%) ingested the colon capsule. A total of 451 videos were analyzed, and in 94.7% the capsule reached the descending colon. At least 1 abnormal finding was seen in 448 (99.3%) participants. The prevalence of abnormalities per GI segment, and the most common type of abnormality, were as follows: Esophageal 14.8% (Barrett's esophagus <3 cm in 8.3%), gastric 27.9% (fundic gland polyps in 18.1%), SB abnormalities 33.9% (erosions in 23.8%), colon 93.3% (diverticula in 81.2%). A total of 54 participants (12%) had clinically relevant abnormalities, 3 (0.7%) in esophagus/stomach (reflux esophagitis grade D, Mallory Weiss lesion and severe gastritis), 5 (1.1%) in SB (polyps > 10 mm; n = 4, severe ulcer n = 1,) and 46 (10.2%) in colon (polyp > 10 mm or ≥3 polyps n = 46, colorectal cancer n = 1).

CONCLUSIONS

GI lesions are very common in a mostly asymptomatic Western population, and clinically relevant lesions were found in 12% at CCE. These findings provide a frame of reference for the prevalence rates of GI lesions in the general population.

The effect of train-the-colonoscopy-trainer course on colonoscopy quality indicators

BACKGROUND

Systematic training in colonoscopy is highly recommended; however, we have limited knowledge of the effects of "training-the-colonoscopy-trainer" (TCT) courses. Using a national quality register on colonoscopy performance, we aimed to evaluate the effects of TCT participation on defined quality indicators.

METHODS

This observational study compared quality indicators (pain, cecal intubation, and polyp detection) between centers participating versus not participating in a TCT course. Nonparticipating centers were assigned a pseudoparticipating year to match their participating counterparts. Results were compared between first year after and the year before TCT (pseudo)participation. Time trends up to 5 years after TCT (pseudo)participation were also compared. Generalized estimating equation models, adjusted for age, sex, and bowel cleansing, were used.

RESULTS

11 participating and 11 nonparticipating centers contributed 18 555 and 10 730 colonoscopies, respectively. In participating centers, there was a significant increase in detection of polyps ≥ 5 mm, from 26.4 % to 29.2 % (P = 0.035), and reduction in moderate/severe pain experienced by women, from 38.2 % to 33.6 % (P = 0.043); no significant changes were found in nonparticipating centers. Over 5 years, 20 participating and 18 nonparticipating centers contributed 85 691 and 41 569 colonoscopies, respectively. In participating centers, polyp detection rate increased linearly (P = 0.003), and pain decreased linearly in women (P = 0.004). Nonparticipating centers did not show any significant time trend during the study period.

CONCLUSIONS

Participation in a TCT course improved polyp detection rates and reduced pain experienced by women. These effects were maintained during a 5-year follow-up.

TEACHING BASIC COLONOSCOPY SKILLS: QUALITY AND SAFETY STANDARDS CAN BE FULFILLED IN AN OUTPATIENT UNIVERSITY CENTER

BACKGROUND

Recent studies have shown that endoscopy fellows can perform colonoscopy effectively and safely. However, little is known about the performance of surgical residents without prior knowledge of endoscopic techniques.

OBJECTIVE

To assess whether quality indicators were met at an outpatient endoscopy center and whether surgical residents, without prior upper or lower endoscopy skills, could perform colonoscopy adequately.

METHODS

A prospective non-randomized cohort study was undertaken. All exams were performed either by assistant physicians or by residents. Quality measures were compared between those groups.

RESULTS

A total of 2720 colonoscopies were analyzed. In the resident group, we observed older patients (57.7±12.7 years vs 51.5±14.5 years, P<0.001), a higher prevalence of screening colonoscopies (52% vs 39.4%, P<0.001) and a higher prevalence of colorectal cancer (6.4% vs 1.8%, P<0.001). The cecal intubation rate was higher in the attending group (99.9% vs 89.3%; P<0.001). The polyp detection rate was 40.8%, and no differences were observed between the studied groups. The residents had a higher rate of perforation in all exams (0.4% vs 0%; P=0.02). Postpolypectomy bleeding and 7-day readmission rates were the same (0.2%). All readmissions in 7 days occurred due to low digestive bleeding, and none required intervention.

CONCLUSION

Quality indicators were met at a university outpatient endoscopy center; however, medical residents achieved lower rates of cecal intubation and higher rates of perforation than the attending physicians.

Colonoscopy screening and surveillance guidelines

The Colonoscopy Screening and Surveillance Guidelines were developed by the Japan Gastroenterological Endoscopy Society as basic guidelines based on the scientific methods. The importance of endoscopic screening and surveillance for both detection and post-treatment follow-up of colorectal cancer has been recognized as essential to reduce disease mortality. There is limited high-level evidence in this field; therefore, we had to focus on the consensus of experts. These clinical practice guidelines consist of 20 clinical questions and eight background knowledge topics that have been determined as the current guiding principles.

Association Between Polyp Detection Rate and Post-Colonoscopy Cancer Among Patients Undergoing Diagnostic Colonoscopy

Postcolonoscopy colorectal cancer (PCCRC) can arise from missed cancers, missed premalignant lesions, incomplete resection, and new cancers with an accelerated route to cancer.¹.

Polyp Detection Rate Correlates Strongly with Adenoma Detection Rate in Trainee Endoscopists

BACKGROUND

The adenoma detection rate (ADR) is a widely accepted quality benchmark for screening colonoscopy but can be burdensome to calculate. Previous studies have shown good correlation between polyp detection rate (PDR) and ADR, but this has not been validated in trainees. Additionally, the correlation between PDR and detection rates for sessile serrated polyps (SSPDR) and advanced neoplasia (ANDR) is not well studied.

AIMS

We investigated the relationship between PDR and ADR, SSPDR, and ANDR in trainees.

METHODS

We examined 1600 outpatient colonoscopies performed by 24 trainees at a VA hospital from 2014 to 2017. Variables collected included patient demographics, year of fellowship, colonoscopy indication, and endoscopic and histologic findings. We calculated the overall ratios of PDR to ADR, SSPDR, and ANDR to assess the correlation between measured and calculated ADR, SSPDR, and ANDR, which is equivalent to the correlation between PDR and measured ADR, SSPDR, and ANDR.

RESULTS

The overall PDR, ADR, SSPDR, and ANDR were 72%, 52%, 2%, and 14%. PDR (48%) was highest in the left colon, while ADR (32%) and ANDR (7%) were highest in the right colon (p < 0.001 for all). The overall ADR/PDR, SSPDR/PDR, and ANDR/PDR ratios were 0.73, 0.03, and 0.20. Correlation between PDR and ADR was highly positive overall (r = 0.87, p < 0.0001) and stronger in the right (r = 0.91) and transverse (r = 0.94) colon than the left colon (r = 0.80). Correlation between PDR and overall SSPDR and ANDR were not statistically significant.

CONCLUSIONS

PDR can serve as a surrogate measure of ADR to monitor colonoscopy quality in gastroenterology fellowship.

Implementing visual cues to improve the efficacy of screening colonoscopy: exploiting the Hawthorne effect

Background:

Colonoscopy is the gold standard for colon cancer screening. Adenoma detection rate and a withdrawal time of 6 min are quality metrics to measure the efficacy of colonoscopy in colon cancer screening. The aim of our study was to exploit the Hawthorne effect in an effort to ensure adherence to a minimum 6-min withdrawal time and subsequently increase adenoma detection rate.

Methods:

This was a retrospective single-center study where we reviewed the records of patients who underwent screening colonoscopy in 2015 and 2017. We divided our patient population into 2 groups. The first group of patients from 2015 underwent screening colonoscopy with no visual cues on the colonoscopy monitor. The second group of patients from 2017 had visual cues indicating withdrawal time on the colonoscopy monitor.

Results:

Screening colonoscopy had a statistically significantly higher adenoma detection rate when performed with visual cues compared to without visual cues (25.3% vs. 19.45, P=0.04). Polyp detection rate was also higher in the group where visual cueing was used (52.9% vs. 22.9%, P<0.001). There were no statistically significant differences in actual withdrawal time or cecal intubation rates.

Conclusions:

Visual cues indicating withdrawal time are a useful intervention that results in an increased adenoma detection rate. Given its practicality and cost effectiveness, we recommend universally implementing visual cues to ensure adherence to a minimum 6-min withdrawal time.

Morning versus afternoon adenoma detection rate: a systematic review and meta-analysis

Adenoma detection rate (ADR) is a quality marker of colonoscopy and operator performance. Prior studies evaluating the effect of an extended workday on the ADR reported variable outcomes that remain controversial. Given the variable results of prior studies and the potential legal implications of reduced ADR in the afternoon, we aimed to further evaluate this parameter and its effect on ADR. We performed a systematic review of the PubMed, CINAHL and Scopus electronic databases. Studies were included if they reported ADR in patients undergoing colonoscopy in the morning session and the afternoon session. Afternoon sessions included both sessions following a morning shift and half-day block shifts. Subgroup analyses were performed for ADR comparing morning and afternoon colonoscopies in a continuous workday, advanced ADRs (AADRs) and polyp detection rates (PDRs) were also compared. Thirteen articles with 17 341 (61.2%) performed in the morning session and 10 994 (38.8%) performed in the afternoon session were included in this study. There was no statistical significance in the ADR or AADR between morning and afternoon sessions, respectively [relative risk (RR) 1.06, 95% confidence interval (CI) 0.99-1.14] and (RR 1.19, 95% CI 0.95-1.5). Afternoon procedures had a significantly higher PDR than morning procedures (RR 0.93, 95% CI 0.88-0.98). ADR was not significantly influenced in the afternoon session when operators continued to perform procedures throughout the day or on a half-day block schedule.

Impact of moderate versus deep sedation on adenoma detection rate in index average-risk screening colonoscopies

BACKGROUND AND AIMS

The debate between moderate sedation versus deep sedation for index average-risk screening colonoscopies is well known to gastroenterologists. Ensuring the best of all metrics to perform quality colonoscopies for colon cancer prevention is paramount for both patients and physicians alike, because colon cancer remains the leading cause of cancer death and is the most-used screening tool in the United States. The aim of this study was to determine if moderate sedation versus deep sedation affects outcomes of adenoma detection rate (ADR) or polyp detection rate (PDR) in index, average-risk colonoscopies for colon cancer screening.

METHODS

A retrospective, single, tertiary care outpatient center study of 585 healthy average-risk patients who underwent index screening colonoscopy between June 1, 2015 to December 31, 2015 (moderate sedation only) and June 1, 2016,to December 31, 2016 (deep sedation only) was performed after Institutional Review Board approval. Demographic data and polyp details were collected to determine ADR and PDR. Patients who were not average risk were excluded from the study.

RESULTS

A total of 585 index average-risk screening colonoscopies were included in this study with 57.7% moderate sedation and 42.2% deep sedation. Neither ADR nor PDR was significantly different between the 2 groups (44.1% vs 38.5% [P = .18] and 71.9% vs 67.6% [P = .27], respectively).

CONCLUSIONS

In index average-risk screening colonoscopies, deep sedation appears to have no benefit compared with moderate sedation for ADR and PDR.

Factors associated with polyp detection during colonoscopy: A retrospective observational study

The polyp detection rate (PDR) is an important quality indicator for colonoscopy. Several factors have been shown to be associated with PDR. However, whether the moderate sedation is a factor for polyp detection remains controversial. This study aims to assess factors associated with polyp detection including the moderate sedation factor during colonoscopy. Patients who underwent colonoscopy from June 1, 2014 to May 31, 2015 were enrolled into this retrospective study. Patients with poor colon preparation and failure to reach the cecum were excluded. The clinical factors, including patient's sex, age, midazolam/fentanyl sedation, indications, endoscopist colonoscopy volume, and use of antispasmodic agent were evaluated by multivariate analysis. A total of 3373 patients were included in this study. The mean age was 55.8 years, and 1980 patients (58.7%) were male. Among the 3373 patients, 2513 (74.5%) underwent midazolam/fentanyl-based sedated colonoscopy. The multivariate analysis showed that male sex, age over 50 years old, midazolam/fentanyl sedation and indications of screening and surveillance were significantly associated with polyp detection. Moreover, when stratified by sex and age, the midazolam/fentanyl sedation was associated with polyp detection in male patients and patients over 50 years old. This study has highlighted the role of midazolam/fentanyl sedation administered by colonoscopists as a modifiable factor that may increase polyp detection during colonoscopy.

Data quality and colonoscopy performance indicators in the prevalent round of a FIT-based colorectal cancer screening program

Objective: From the prevalent round of the Danish FIT-based colorectal cancer (CRC) screening program, we aimed (i) to evaluate the quality of recorded data and (ii) to characterize the colonoscopies by measuring variation in performance indicators between colonoscopists and assessing the ratio between adenoma detection rate (ADR) and polyp detection rate (PDR). Materials and methods: This study included screening colonoscopies performed in Central Denmark Region within 60 days of a positive FIT-result from 1 July 2015 through 30 June 2017. The participants were the colonoscopists, performing these procedures. The quality indicators cecal intubation rate (CIR), PDR, polyp retrieval rate (PRR), ADR and withdrawal time (WT) were evaluated. ADR/PDR ratios were calculated. Results: The concordance between the recorded data and the colonoscopy reports showed Kappa values in the range of 0.47-0.97. The overall CIR was 90.6% (range 73.7%-100%), PDR: 51.9% (range 18.4%-70.2%), PRR: 94.6% (range 69.6%-100%), ADR (conventional adenomas): 50.6% (range 18.4%-70.2%), ADRx (conventional adenomas, traditional serrated adenomas and sessile serrated lesions with dysplasia): 50.9% (range 18.4%-70.2%) and the mean WT was 11.3 min (range 4.5-24.9 min). The ADR/PDR ratio was 92.8% (95% CI: 92.0%-93.6%) and the ADRx/PDR ratio was 93.2% (95% CI: 92.4%-93.9%). Conclusion: Data quality was generally high. We found considerable variation in performance indicators between colonoscopists reflecting the potential for improvement. Further, our findings revealed that the PDR might be a good proxy for ADR in the context of the prevalent round of FIT-based CRC screening programs.