Automated classification pipeline for real-time in vivo examination of colorectal tissue using Raman spectroscopy

Colorectal cancer is the third most common malignancy worldwide and one of the leading causes of death in oncological patients with its diagnosis typically involving confirmation by tissue biopsy. In vivo Raman spectroscopy, an experimental diagnostic method less invasive than a biopsy, has shown great potential to discriminate between normal and cancerous tissue. However, the complex and often manual processing of Raman spectra along with the absence of a suitable instant classifier are the main obstacles to its adoption in clinical practice. This study aims to address these issues by developing a real-time automated classification pipeline coupled with a user-friendly application tailored for non-spectroscopists. First, in addition to routine colonoscopy, 377 subjects underwent in vivo acquisitions of Raman spectra of healthy tissue, adenomatous polyps, or cancerous tissue, which were conducted using a custom-made microprobe. The spectra were then loaded into the pipeline and pre-processed in several steps, including standard normal variate transformation and finite impulse response filtration. The quality of the pre-processed spectral data was checked based on their signal-to-noise ratio before the suitable spectra were decomposed and classified using a combination of principal component analysis and a support vector machine, respectively. After five-fold cross-validation, the developed classifier exhibited 100% sensitivity toward adenocarcinoma and adenomatous polyps. The overall accuracy was 96.9% and 79.2% for adenocarcinoma and adenomatous polyps respectively. In addition, an application with a graphical user interface was developed to facilitate the use of our data pipeline by medical professionals in a clinical environment. Overall, the combination of supervised and unsupervised machine learning with algorithmic pre-processing of in vivo Raman spectra appears to be a viable way of reducing the relatively large number of biopsies currently needed to definitively diagnose colorectal cancer.

Expert endoscopist assessment of colorectal polyp size using virtual scale endoscopy, visual or snare-based estimation: a prospective video-based study

BACKGROUND AND AIMS

Accurate polyp size estimation during colonoscopy has an impact on clinical decision-making. A laser-based virtual scale endoscope (VSE) is available to allow measuring polyp size using a virtual adaptive scale. This study evaluates video-based polyp size measurement accuracy among expert endoscopists using either VSE or visual assessment (VA) with either snare as reference size or without any reference size information.

METHODS

A prospective, video-based study was conducted with 10 expert endoscopists. Video sequences from 90 polyps with known reference size (fresh specimen measured using calipers) were distributed on three different slide sets so that each slide set showed the same polyp only once with either VSE, VA or snare-based information. A slide set was randomly assigned to each endoscopist. Endoscopists were asked to provide size estimation based on video review.

RESULTS

Relative accuracies for VSE, VA, and snare-based estimation were 75.1% (95% CI [71.6-78.5]), 65.0% (95% CI [59.5-70.4]) and 62.0% (95% CI [54.8-69.0]), respectively. VSE yielded significantly higher relative accuracy compared to VA (p = 0.002) and to snare (p = 0.001). A significantly lower percentage of polyps 1-5 mm were misclassified as >5 mm using VSE versus VA and snare (6.52% vs. 19.6% and 17.5%, p = 0.004) and a significantly lower percentage of polyps >5 mm were misclassified as 1-5 mm using VSE versus VA and snare (11.4% vs. 31.9% and 14.9%, p = 0.038).

CONCLUSIONS

Endoscopists estimate polyp size with the highest accuracy when virtual adaptive scale information is displayed. Using a snare to assist sizing did not improve measurement accuracy compared to displaying visual information alone.

Post-colonoscopy colorectal cancers in a national fecal immunochemical test-based colorectal cancer screening program

BACKGROUND

Post-colonoscopy colorectal cancers (PCCRCs) decrease the effect of colorectal cancer (CRC) screening programs. To enable PCCRC incidence reduction in the long-term, we classified PCCRCs diagnosed after colonoscopies performed in a fecal immunochemical test (FIT)-based screening program.

METHODS

PCCRCs diagnosed after colonoscopies performed between 2014-2016 for a positive FIT in the Dutch CRC screening program were included. PCCRCs were categorized according to the World Endoscopy Organization consensus statement into (a) interval PCCRC (diagnosed before the recommended surveillance); (b) non-interval type A (diagnosed at the recommended surveillance interval); (c) non-interval type B (diagnosed after the recommended surveillance interval); or (d) non-interval type C (diagnosed after the intended recommended surveillance interval, with surveillance not implemented owing to co-morbidity). The most probable etiology was determined by root-cause analysis. Tumor stage distributions were compared between categories.

RESULTS

116362 colonoscopies were performed after a positive FIT with 9978 screen-detected CRCs. During follow-up, 432 PCCRCs were diagnosed. The 3-year PCCRC rate was 2.7%. PCCRCs were categorized as interval (53.5%), non-interval type A (14.6%), non-interval type B (30.6%), and non-interval type C (1.4%). The most common etiology for interval PCCRCs was possible missed lesion with adequate examination (73.6%); they were more often diagnosed at an advanced stage (stage III/IV; 53.2%) compared with non-interval type A (15.9%; P<0.001) and non-interval type B (40.9%; P=0.03) PCCRCs.

CONCLUSIONS

The 3-year PCCRC rate was low in this FIT-based CRC screening program. Approximately half of PCCRCs were interval PCCRCs. These were mostly caused by missed lesions and were diagnosed at a more advanced stage. This emphasizes the importance of high quality colonoscopy with optimal polyp detection.

Linked-color imaging with or without artificial intelligence for adenoma detection: a randomized trial

BACKGROUND

Adenoma detection rate (ADR) is an important indicator of colonoscopy quality and colorectal cancer incidence. Both linked-color imaging (LCI) with artificial intelligence (LCA) and LCI alone increase adenoma detection during colonoscopy, although it remains unclear whether one modality is superior. This study compared ADR between LCA and LCI alone, including according to endoscopists' experience (experts and trainees) and polyp size.

METHODS

Patients undergoing colonoscopy for positive fecal immunochemical tests, follow-up of colon polyps, and abdominal symptoms at a single institution were randomly assigned to the LCA or LCI group. ADR, adenoma per colonoscopy (APC), cecal intubation time, withdrawal time, number of adenomas per location, and adenoma size were compared.

RESULTS

The LCA (n=400) and LCI (n=400) groups showed comparable cecal intubation and withdrawal times. The LCA group showed a significantly higher ADR (58.8% vs. 43.5%; P<0.001) and mean (95%CI) APC (1.31 [1.15 to 1.47] vs. 0.94 [0.80 to 1.07]; P<0.001), particularly in the ascending colon (0.30 [0.24 to 0.36] vs. 0.20 [0.15 to 0.25]; P=0.02). Total number of nonpolypoid-type adenomas was also significantly higher in the LCA group (0.15 [0.09 to 0.20] vs. 0.08 [0.05 to 0.10]; P=0.02). Small polyps (≤5, 6-9mm) were detected significantly more frequently in the LCA group (0.75 [0.64 to 0.86] vs. 0.48 [0.40 to 0.57], P<0.001 and 0.34 [0.26 to 0.41] vs. 0.24 [0.18 to 0.29], P=0.04, respectively). In both groups, ADR was not significantly different between experts and trainees.

CONCLUSIONS

LCA was significantly superior to LCI alone in terms of ADR.

Clinical Predictors of Early and Late Endoscopic Recurrence Following Ileocolonic Resection in Crohn's Disease

BACKGROUND AND AIMS

Multiple factors are suggested to place Crohn's disease patients at risk of recurrence after ileocolic resection with conflicting associations. We aimed to identify clinical predictors of recurrence at first [early] and further [late] postoperative colonoscopy.

METHODS

Crohn's disease patients undergoing ileocolic resection were prospectively recruited at six North American centres. Clinical data were collected and endoscopic recurrence was defined as Rutgeerts score ≥i2. A multivariable model was fitted to analyse variables independently associated with recurrence.

RESULTS

A total of 365 patients undergoing 674 postoperative colonoscopies were included with a median age of 32 years, 189 [51.8%] were male, and 37 [10.1%] were non-Whites. Postoperatively, 133 [36.4%] used anti-tumour necrosis factor [anti-TNF] and 30 [8.2%] were smokers. At first colonoscopy, 109 [29.9%] had recurrence. Male gender (odds ratio [OR] = 1.95, 95% confidence interval [CI] 1.12-3.40), non-White ethnicity [OR = 2.48, 95% CI 1.09-5.63], longer interval between surgery and colonoscopy [OR = 1.09, 95% CI 1.002-1.18], and postoperative smoking [OR = 2.78, 95% CI 1.16-6.67] were associated with recurrence, while prophylactic anti-TNF reduced the risk [OR = 0.28, 95% CI 0.14-0.55]. Postoperative anti-TNF prophylaxis had a protective effect on anti-TNF experienced patients but not on anti-TNF naïve patients. Among patients without recurrence at first colonoscopy, Rutgeerts score i1 was associated with subsequent recurrence [OR = 4.43, 95% CI 1.73-11.35].

CONCLUSIONS

We identified independent clinical predictors of early and late Crohn's disease postoperative endoscopic recurrence. Clinical factors traditionally used for risk stratification failed to predict recurrence and need to be revised.

Initiatives to increase colonoscopy capacity - is there an impact on polyp detection? A UK National Endoscopy Database analysis

BACKGROUND

 To address mismatch between routine endoscopy capacity and demand, centers often implement initiatives to increase capacity, such as weekend working or using locums/agency staff (insourcing). However, there are concerns that such initiatives may negatively impact quality. We investigated polyp detection for weekend vs. weekday and insourced vs. standard procedures using data from the UK National Endoscopy Database.

METHODS

 We conducted a national, retrospective, cross-sectional study of diagnostic colonoscopies performed during 01/01-04/04/2019. The primary outcome was mean number of polyps (MNP) and the secondary outcome was polyp detection rate (PDR). Multi-level mixed-effect regression, fitting endoscopist as a random effect, was used to examine associations between procedure day (weekend/weekday) and type (insourced/standard) and these outcomes, adjusting for patient age, sex, and indication.

RESULTS

 92 879 colonoscopies (weekends: 19 977 [21.5 %]; insourced: 9909 [10.7 %]) were performed by 2496 endoscopists. For weekend colonoscopies, patients were less often male or undergoing screening-related procedures; for insourced colonoscopies, patients were younger and less often undergoing screening-related procedures (all P < 0.05). Fully adjusted MNP was significantly lower for weekend vs. weekday (incidence rate ratio [IRR] 0.86 [95 %CI 0.83-0.89]) and for insourced vs. standard procedures (IRR 0.91 [95 %CI 0.87-0.95]). MNP was highest for weekday standard procedures and lowest for weekend insourced procedures; there was no interaction between procedure day and type. Similar associations were found for PDR.

CONCLUSIONS

 Strategies to increase colonoscopy capacity may negatively impact polyp detection and should be monitored for quality. Reasons for this unwarranted variation require investigation.

Association between pan-immune inflammatory value and ulcerative colitis

OBJECTIVE

Ulcerative colitis is a chronic idiopathic disease that causes inflammation of the colon and rectum, progressing with relapses and remissions. Systemic inflammatory index (SII) and pan-immune inflammatory value (PIV) are newly developed biomarkers. There are many studies in the literature showing the relationship between SII and PIV with malignancies and inflammatory diseases. In this study we aimed to determine the relationship between SII and PIV with the activity of ulcerative colitis.

MATERIALS AND METHODS

146 Ulcerative colitis patients were retrospectively investigated by the time of diagnosis based on clinical, endoscopic and histolopathological findings. Patients and healthy individuals SII and PIV levels were calculated and compared with each other; and Mayo, DUBLIN, UCIES endoscopic subscores of patients were also obtained. Roc curve analysis were used to determine the cut-off value for PIV.

RESULTS

SII (468.6 ± 203.5 vs. 823.1 ± 555.1; p < .001), PIV (288.2 ± 159.9 vs. 912.2 ± 924.1; p < .001), were statistically different between groups. PIV (OR: 1.157; (1.041-1.432), p = .036), was also observed to be the independent predictor of ulcerative colitis. The best cut off value of PIV in the prediction of ulcerative colitis was ≥ 506 with 89.6% sensitivity and 63.7% specificity (AUC = 0.812; 95% CI 0.763-0.854, p < .001).

CONCLUSION

Based on the results of our study, we found that SII and PIV levels were significantly increased in ulcerative colitis patients at the time of diagnosis and were associated with disease severity in the endoscopic scores RACHMILEWITZ, UCEIS and DUBLIN scores, but not for MES score.

Single Versus Second Observer vs Artificial Intelligence to Increase the ADENOMA Detection Rate of Colonoscopy-A Network Analysis

BACKGROUND AND AIMS

Screening colonoscopy has significantly contributed to the reduction of the incidence of colorectal cancer (CRC) and its associated mortality, with adenoma detection rate (ADR) as the quality marker. To increase the ADR, various solutions have been proposed including the utilization of Artificial Intelligence (AI) and employing second observers during colonoscopies. In the interest of AI improving ADR independently, without a second observer, and the operational similarity between AI and second observer, this network meta-analysis aims at evaluating the effectiveness of AI, second observer, and a single observer in improving ADR.

METHODS

We searched the Medline, Embase, Cochrane, Web of Science Core Collection, Korean Citation Index, SciELO, Global Index Medicus, and Cochrane. A direct head-to-head comparator analysis and network meta-analysis were performed using the random-effects model. The odds ratio (OR) was calculated with a 95% confidence interval (CI) and p-value < 0.05 was considered statistically significant.

RESULTS

We analyzed 26 studies, involving 22,560 subjects. In the direct comparative analysis, AI demonstrated higher ADR (OR: 0.668, 95% CI 0.595-0.749, p < 0.001) than single observer. Dual observer demonstrated a higher ADR (OR: 0.771, 95% CI 0.688-0.865, p < 0.001) than single operator. In network meta-analysis, results were consistent on the network meta-analysis, maintaining consistency. No statistical difference was noted when comparing AI to second observer. (RR 1.1 (0.9-1.2, p = 0.3). Results were consistent when evaluating only RCTs. Net ranking provided higher score to AI followed by second observer followed by single observer.

CONCLUSION

Artificial Intelligence and second-observer colonoscopy showed superior success in Adenoma Detection Rate when compared to single-observer colonoscopy. Although not statistically significant, net ranking model favors the superiority of AI to the second observer.

Two-stage deep-learning-based colonoscopy polyp detection incorporating fisheye and reflection correction

BACKGROUND AND AIM

Colonoscopy is a useful method for the diagnosis and management of colorectal diseases. Many computer-aided systems have been developed to assist clinicians in detecting colorectal lesions by analyzing colonoscopy images. However, fisheye-lens distortion and light reflection in colonoscopy images can substantially affect the clarity of these images and their utility in detecting polyps. This study proposed a two-stage deep-learning model to correct distortion and reflections in colonoscopy images and thus facilitate polyp detection.

METHODS

Images were collected from the PolypSet dataset, the Kvasir-SEG dataset, and one medical center's patient archiving and communication system. The training, validation, and testing datasets comprised 808, 202, and 1100 images, respectively. The first stage involved the correction of fisheye-related distortion in colonoscopy images and polyp detection, which was performed using a convolutional neural network. The second stage involved the use of generative and adversarial networks for correcting reflective colonoscopy images before the convolutional neural network was used for polyp detection.

RESULTS

The model had higher accuracy when it was validated using corrected images than when it was validated using uncorrected images (96.8% vs 90.8%, P < 0.001). The model's accuracy in detecting polyps in the Kvasir-SEG dataset reached 96%, and the area under the receiver operating characteristic curve was 0.94.

CONCLUSION

The proposed model can facilitate the clinical diagnosis of colorectal polyps and improve the quality of colonoscopy.

Cold Snare Polypectomy in Small (<10 mm) Pedunculated Colorectal Polyps: A Systematic Review and Meta-analysis

INTRODUCTION

Endoscopic removal techniques for colorectal polyps include cold snare polypectomy (CSP) and hot snare polypectomy (HSP). Although HSP is recommended for pedunculated polyps (PPs) larger than 10 mm, data regarding use of CSP for PPs <10 mm continues to emerge. We aimed to investigate outcomes of these techniques in small (<10 mm) pedunculated colorectal polyps.

METHODS

Multiple databases were searched till June 2022 to identify studies involving the removal of small PPs with CSP and HSP. Random effects model was used to calculate outcomes and 95% CI. Primary outcome was the pooled rate of successful en-bloc resection. Secondary outcomes were immediate and delayed bleeding with CSP and HSP as well as prophylactic and post resection clip placement.

RESULTS

Six studies including 1025 patients (1111 polyps with a mean size 4 to 8.5 mm) were analyzed. 116 and 995 polyps were removed with HSP and CSP, respectively. The overall pooled rate of successful en-bloc resection with CSP was 99.7% (CI 99.1-99.9; I2 0%). Pooled immediate and delayed bleeding after CSP was 49.8% (CI 46.8-52.91; I2 98%) and 0% (CI 0.00-0.00; I2 0%), respectively. Delayed bleeding was higher with HSP, relative risk 0.05 (CI 0.01-0.43; I2 0%), P =0.006, whereas immediate bleeding was higher with CSP, relative risk 7.89 (CI 4.36-14.29; I2 0%), P <0.00001. Pooled rates of prophylactic clip placement and post-procedure clip placement (to control immediate bleeding) were 55.3% and 47.2%, respectively. Finally, right colon polyp location significantly correlated with frequency of immediate bleeding.

CONCLUSION

Our analysis shows that CSP is safe and effective for resection of small PPs.

A novel low-power pure-cut hot snare polypectomy for 10-14 mm colorectal adenomas: An ex vivo and a clinical prospective feasibility study (SHARP trial)

BACKGROUND AND AIM

Hot snare polypectomy using blend or coagulation current is widely used; however, it causes deeper tissue heat injury, leading to adverse events. We hypothesized that hot polypectomy using low-power pure cut current (PureCut, effect 1 10 W) could reduce deeper tissue heat injury. We conducted animal experiments to evaluate the deeper tissue heat injury and conducted a prospective clinical study to examine its cutting ability.

METHODS

In a porcine rectum, hot polypectomy using Blend current (EndoCut, effect 3 40 W) and low-power pure cut current was performed. The deepest part of heat destruction and thickness of the non-burned submucosal layer were evaluated histologically. Based on the results, we performed low-power pure cut current hot polypectomy for 10-14 mm adenoma. The primary endpoint was complete resection defined as one-piece resection with negative for adenoma in quadrant biopsies from the defect margin.

RESULTS

In experiments, all low-power pure-cut resections were limited within the submucosal layer whereas blend current resections coagulated the muscular layer in 13% (3/23). The remaining submucosal layer was thicker in low-power pure cut current than in blend current resections. In the clinical study, low-power pure-cut hot polypectomy removed all 100 enrolled polyps. For 98 pathologically neoplastic polyps, complete resection was achieved in 84 (85.7%, 95% confidence interval, 77-92%). The lower limit of the 95% confidence interval was not more than 15% below the pre-defined threshold of 86.6%. No severe adverse events occurred.

CONCLUSIONS

A novel low-power pure-cut hot polypectomy may be feasible for adenoma measuring 10-14 mm. (UMIN000037678).

Novel cold snare technique with clipping for duodenal angioectasia

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Updates on the Prevention and Management of Post-Polypectomy Bleeding in the Colon

Post-polypectomy bleeding (PPB) remains a significant procedure-related complication, with multiple risk factors determining the risk including patient demographics, polyp characteristics, endoscopist expertise, and techniques of polypectomy. Immediate PPB is usually treated promptly, but management of delayed PPB can be challenging. Cold snare polypectomy is the optimal technique for small sessile polyps with hot snare polypectomy for pedunculated and large sessile polyps. Topical hemostatic powders and gels are being investigated for the prevention and management of PPB. Further studies are needed to compare these topical agents with conventional therapy.

Linked-color imaging versus high definition white-light endoscopy for evaluation of post-polypectomy scars of nonpedunculated lesions: LCI-Scar study

BACKGROUND

Detection and treatment of recurrence after piecemeal endoscopic mucosal resection of nonpedunculated colorectal polyps are crucial for avoidance of post-colonoscopy cancer. Linked-color imaging (LCI) has demonstrated improved polyp detection but has never been assessed for evaluation of post-polypectomy scars. Our aim was to compare sensitivity and negative predictive value (NPV) between LCI and white-light endoscopy (WLE) for detection of post-polypectomy recurrence.

METHODS

Patients undergoing surveillance colonoscopy after resection of lesions ≥15 mm were included in this prospective, single-center, randomized, crossover study. Each post-polypectomy scar underwent two examinations, one with LCI and the other with WLE, performed by two blinded endoscopists. Blue-light imaging (BLI) was then applied. A diagnosis of recurrence with a level of confidence was made for each modality and histopathology was the gold standard.

RESULTS

129 patients with 173 scars were included. Baseline patient, lesion, and procedural characteristics were similar in both arms. Recurrence was detected in 56/173 (32.4%), with 27/56 (48.2%) adenomas and 29/56 (51.8%) serrated lesions. LCI had greater sensitivity (96.4% [95%CI 87.8%-99.5%]) versus WLE (89.3% [95%CI 78.1%-95.9%]) and greater NPV (98.1% [95%CI 93.4%-99.8%] versus 94.6% [95%CI 88.7%-98.0%]). Paired concordance between modalities was 96.0%. In discordant cases, LCI identified four true-positive cases not detected by WLE and reclassified one false-positive of WLE. WLE reclassified two false positives of LCI without any increase in recurrence detection.

CONCLUSIONS

LCI was highly accurate and had greater ability than WLE to rule out recurrence on post-polypectomy scars after resection of large polyps.

A real-time deep learning-based system for colorectal polyp size estimation by white-light endoscopy: development and multicenter prospective validation

BACKGROUND

The choice of polypectomy device and surveillance intervals for colorectal polyps are primarily decided by polyp size. We developed a deep learning-based system (ENDOANGEL-CPS) to estimate colorectal polyp size in real time.

METHODS

ENDOANGEL-CPS calculates polyp size by estimating the distance from the endoscope lens to the polyp using the parameters of the lens. The depth estimator network was developed on 7297 images from five virtually produced colon videos and tested on 730 images from seven virtual colon videos. The performance of the system was first evaluated in nine videos of a simulated colon with polyps attached, then tested in 157 real-world prospective videos from three hospitals, with the outcomes compared with that of nine endoscopists over 69 videos. Inappropriate surveillance recommendations caused by incorrect estimation of polyp size were also analyzed.

RESULTS

The relative error of depth estimation was 11.3% (SD 6.0%) in successive virtual colon images. The concordance correlation coefficients (CCCs) between system estimation and ground truth were 0.89 and 0.93 in images of a simulated colon and multicenter videos of 157 polyps. The mean CCC of ENDOANGEL-CPS surpassed all endoscopists (0.89 vs. 0.41 [SD 0.29]; P<0.001). The relative accuracy of ENDOANGEL-CPS was significantly higher than that of endoscopists (89.9% vs. 54.7%; P<0.001). Regarding inappropriate surveillance recommendations, the system's error rate is also lower than that of endoscopists (1.5% vs. 16.6%; P<0.001).

CONCLUSIONS

ENDOANGEL-CPS could potentially improve the accuracy of colorectal polyp size measurements and size-based surveillance intervals.

Characteristics of flat-type ulcerative colitis-associated neoplasia on chromoendoscopic imaging with indigo carmine dye spraying

OBJECTIVES

Despite recent advances in endoscopic equipment and diagnostic techniques, early detection of ulcerative colitis-associated neoplasia (UCAN) remains difficult because of the complex background of the inflamed mucosa of ulcerative colitis and the morphologic diversity of the lesions. We aimed to describe the main diagnostic patterns for UCAN in our cohort, including lateral extension surrounding flat lesions.

METHODS

Sixty-three lesions in 61 patients with flat-type dysplasia that were imaged with dye chromoendoscopy (DCE) were included in this analysis. These DCE images were analyzed to clarify the dye-chromoendoscopic imaging characteristics of flat dysplasia, and the lesions were broadly classified into dysplastic and nondysplastic mucosal patterns.

RESULTS

Dysplastic mucosal patterns were classified into two types: small round patterns with round to roundish structures, and mesh patterns with intricate mesh-like structures. Lesions with a nondysplastic mucosal pattern were divided into two major types: a ripple-like type and a gyrus-like type. Of note, 35 lesions (55.6%) had a small round pattern, and 51 lesions (80.9%) had some type of mesh pattern. About 70% of lesions with small round patterns and 49% of lesions with mesh patterns were diagnosed as high-grade dysplasia or carcinoma, while about 30% of lesions with small round patterns and 51% of lesions with mesh patterns were diagnosed as low-grade dysplasia.

CONCLUSION

When a characteristic mucosal pattern, such as a small round or mesh pattern, is found by DCE, the possibility of UCAN should be considered.

1-L polyethylene glycol + ascorbic acid versus sodium picosulfate + magnesium citrate bowel preparations for colonoscopy: effectiveness and safety

BACKGROUND

adequate bowel preparation is crucial for the protective effect of colonoscopy. Commonly used preparation regimens like polyethylene glycol (PEG) or sodium picosulfate with magnesium citrate (SPMC) have shown similar results in clinical trials, but low-volume PEG + ascorbic acid (1-L PEG + ASC) versus SPMC have never been compared in a real-life setting.

AIM

to evaluate the effectiveness and safety of 1-L PEG + ASC versus SPMC in a real-life setting for the overall population, for patients aged ≥ 65 years, and males versus females.

METHODS

out-patients aged ≥ 18 years who underwent colonoscopy for any indication were randomly assigned to the 1-L PEG + ASC or SPMC group. Using the Boston Bowel Preparation Scale (BBPS), the primary endpoints were the bowel cleansing success of the overall colon and right colon, as well as high-quality (HQ) cleansing. Furthermore, the effectiveness and safety outcomes for age groups and males versus females were compared.

RESULTS

1-L PEG + ASC showed significantly better bowel cleansing success than SPMC. Particularly remarkable is the HQ cleansing reached with 1-L PEG + ASC compared with SPMC (55.5 % versus 25.4 % in the overall colon, and 58.7 % versus 27.2 % in the right colon). 1-L PEG + ASC was equally effective for men and women while SPMC showed significant differences between genders (men had worse bowel cleansing). Age did not affect the cleansing effectiveness. 1-L PEG + ASC versus SPMC showed significant differences in tolerance and safety; women also had significantly worse tolerance than men for both solutions, but these did not affect the quality of bowel cleansing.

CONCLUSIONS

in our real-life setting, 1-L PEG + ASC offered better adequate and HQ bowel cleansing than SPMC, achieving excellent cleansing quality, regardless of gender or tolerance.

Cold-snare endoscopic resection of non-ampullary duodenal adenomas: Systematic review and pooled-analysis

BACKGROUND

Mirroring the experience with colonic resections, cold snare-based techniques have been recently proposed for non-ampullary duodenal lesions to reduce the risk of adverse events (AEs). As the duodenal wall is thinner and more vascularized than in the colon, electrocautery-related AEs are relevant issues in this setting.

AIMS

We performed a systematic review with pooled-analysis to evaluate the efficacy and safety of this technique.

METHODS

Electronic databases (Medline, Scopus, EMBASE) were searched up to January 2023. Full articles including patients with duodenal lesions resected by cold-snare technique were eligible. The adverse events (i.e., bleeding, perforation, stricture), complete resection, and recurrence rates were pooled using a random model.

RESULTS

Eleven studies were eligible, providing data on 3137 lesions removed from 233 patients. The overall AE rate for cold snaring was 0.25% (95% CI, 0.19%-0.69%). Among the three studies comparing cold- and hot-snare approaches, procedure-related bleeding rate was significantly lower with cold approach (OR 1.21, 0.51-2.85; p = 0.66). The complete resection rate was 99.40% (95% CI, 98.60%-100%), with a residual/recurrence rate of 12.95% (95% CI, 4.75%-21.16%). On univariate meta-regression, lesion size significantly affected both the adverse events and recurrence risk.

CONCLUSION

Cold-snare resection appears effective and extremely safe for resecting non-ampullary duodenal lesions.

The Effects of Combined Use of Linaclotide and Polyethylene Glycol Electrolyte Powder in Colonoscopy Preparation for Patients With Chronic Constipation

OBJECTIVE

The purpose of this study is to evaluate the safety and efficacy of linaclotide and polyethylene glycol (PEG) electrolyte powder in patients with chronic constipation undergoing colonoscopy preparation.

PATIENTS AND METHODS

We included 260 patients with chronic constipation who were scheduled to undergo a colonoscopy. They were equally divided into 4 groups using a random number table: 4L PEG, 3L PEG, 3L PEG+L, and 2L PEG+L. The 4 groups were compared based on their scores on the Boston Bowel Preparation Scale (BBPS) and Ottawa Bowel Preparation Quality Scale (OBPQS), adverse reactions during the bowel preparation procedure, colonoscope insertion time, colonoscope withdrawal time, detection rate of adenomas, and their willingness to repeat bowel preparation.

RESULTS

In terms of the score of the right half of the colon, the score of the transverse colon, the total score using BBPS, and the total score using OBPQS, the 3L PEG (polyethylene glycol)+L group was superior to groups 3L PEG and 2L PEG+L ( P <0.05), but comparable to the 4L PEG group ( P >0.05). The incidence rate of vomiting was higher in the 4L PEG group than in the 2L PEG+L group ( P <0.05). There was no statistically significant difference in the insertion time of the colonoscope between the 4 groups. The colonoscope withdrawal time in the 3L PEG+L group was shorter than in groups 4L PEG and 3L PEG ( P <0.05) and comparable to that in the 4L PEG group ( P >0.05). There was no statistically significant difference in the rate of adenoma detection among the 4 groups ( P >0.05). The 4L PEG group was the least willing of the 4 groups to undergo repeated bowel preparation ( P <0.05).

CONCLUSION

The 3L PEG+L is optimal among the 4 procedures. It can facilitate high-quality bowel preparation, reduce the incidence of nausea during the bowel preparation procedure, and encourage patients to undertake repeated bowel preparation.

The association between organised colorectal cancer screening strategies and reduction of its related mortality: a systematic review and meta-analysis

BACKGROUND

To assess the long-term association between organised colorectal cancer (CRC) screening strategies and CRC-relate mortality.

METHODS

We systematically reviewed studies on organised CRC screening through PubMed, Ovid Medline, Embase and Cochrane from the inception. We retrieved characteristics of organised CRC screening from included literature and matched mortality (over 50 years) of those areas from the International Agency for Research on Cancer in May 2023. The variations of mortality were reported via the age-standardised mortality ratio. A random-effects model was used to synthesis results.

RESULTS

We summarised 58 organised CRC screening programmes and recorded > 2.7 million CRC-related deaths from 22 countries where rollout screening programmes were performed. The CRC screening strategy with faecal tests (guaiac faecal occult blood test (gFOBT) or faecal immunochemical tests (FIT)) or colonoscopy as the primary screening offer was associated with a 41.8% reduction in mortality, which was higher than those offered gFOBT (4.4%), FIT (16.7%), gFOBT or FIT (16.2%), and faecal tests (gFOBT or FIT) or flexible sigmoidoscopy (16.7%) as primary screening test. The longer duration of screening was associated with a higher reduction in the pooled age-standardised mortality ratio. In particular, the pooled age-standardised mortality ratio became non-significant when the screening of FIT was implemented for less than 5 years.

CONCLUSIONS

A CRC screening programme running for > 5 years was associated with a reduction of CRC-related mortality. Countries with a heavy burden of CRC should implement sustainable, organised screening providing a choice between faecal tests and colonoscopy as a preferred primary test.

Cold EMR vs. Hot EMR for the removal of sessile serrated polyps larger than 10 mm: a systematic review and meta-analysis

BACKGROUND

Endoscopic mucosal resection (EMR) appears to be a promising technique for the removal of sessile serrated polyps (SSPs) ≥ 10 mm. To assess the effectiveness and safety of EMR for removing SSPs ≥ 10 mm, we conducted this systematic review and meta-analysis.

METHODS

We conducted a thorough search of Embase, PubMed, Cochrane, and Web of Science databases for relevant studies reporting on EMR of SSPs ≥ 10 mm, up until December 2023. Our primary endpoints of interest were rates of technical success, residual SSPs, and adverse events (AE).

RESULTS

Our search identified 426 articles, of which 14 studies with 2262 SSPs were included for analysis. The rates of technical success, AEs, and residual SSPs were 100%, 2.0%, and 3.1%, respectively. Subgroup analysis showed that the technical success rates were the same for polyps 10-19 and 20 mm, and en-bloc and piecemeal resection. Residual SSPs rates were similar in en-bloc and piecemeal resection, but much lower in cold EMR (1.0% vs. 4.2%, P = 0.034). AEs rates were reduced in cold EMR compared to hot EMR (0% vs. 2.9%, P = 0.168), in polyps 10-19 mm compared to 20 mm (0% vs. 4.1%, P = 0.255), and in piecemeal resection compared to en-bloc (0% vs. 0.7%, P = 0.169).

CONCLUSIONS

EMR is an effective and safe technique for removing SSPs ≥ 10 mm. The therapeutic effect of cold EMR is superior to that of hot EMR, with a lower incidence of adverse effects.

PROSPERO REGISTRATION NUMBER

CRD42023388959.

Cost-Utility Analysis for Colorectal Cancer Screening According to the Initiating Age of National Cancer Screening Program in Korea

BACKGROUND

This study aimed to identify the most cost-effective strategy for colorectal cancer screening using the fecal immunochemical test (FIT), focusing on screening initiation age in Korea.

METHODS

We designed Markov simulation models targeting individuals aged 40 years or older. Twelve strategies combining screening initiation ages (40, 45, or 50 years old), termination ages (80 or no limit), and intervals (1 or 2 years) were modeled, and the most cost-effective strategy was selected. The robustness of the results was confirmed using one-way and probabilistic sensitivity analyses. Furthermore, the cost-effectiveness of the qualitative and quantitative FIT methods was verified using scenario analysis.

RESULTS

The 2-year interval strategy with a screening age range of 45-80 years was the most cost-effective (incremental cost-utility ratio = KRW 7,281,646/quality adjusted life years). The most sensitive variables in the results were transition rate from advanced adenoma to local cancer and discount rate. The uncertainty in the model was substantially low. Moreover, strategies starting at the age of 40 years were also cost-effective but considered suboptimal. The scenario analysis showed that there was no significant difference in cost-effectiveness between strategies with various relative screening ratio of quantitative and qualitative method.

CONCLUSION

The screening method for advancing the initiation age, as presented in the 2015 revised national screening recommendations, was superior regarding cost-effectiveness. This study provides a new paradigm for the development of a national cancer screening system in Korea, which can be utilized as a scientific basis for economic evaluations.

HOT VERSUS COLD SNARE FOR COLORECTAL POLYPECTOMIES SIZED UP TO 10MM: A SYSTEMATIC REVIEW AND META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS

BACKGROUND

Colorectal cancer is the third most common cancer, and prevention relies on screening programs with resection complete resection of neoplastic lesions.

OBJECTIVE

We aimed to evaluate the best snare polypectomy technique for colorectal lesions up to 10 mm, focusing on complete resection rate, and adverse events.

METHODS

A comprehensive search using electronic databases was conducted to identify randomized controlled trials comparing hot versus cold snare resection for polyps sized up to 10 mm, and following PRISMA guidelines, a meta-analysis was performed. Outcomes included complete resection rate, en bloc resection rate, polypectomy, procedure times, immediate, delayed bleeding, and perforation.

RESULTS

Nineteen RCTs involving 8720 patients and 17588 polyps were included. Hot snare polypectomy showed a higher complete resection rate (RD, 0.02; 95%CI [+0.00,0.04]; P=0.03; I 2=63%), but also a higher rate of delayed bleeding (RD 0.00; 95%CI [0.00, 0.01]; P=0.01; I 2=0%), and severe delayed bleeding (RD 0.00; 95%CI [0.00, 0.00]; P=0.04; I 2=0%). Cold Snare was associated with shorter polypectomy time (MD -46.89 seconds; 95%CI [-62.99, -30.79]; P<0.00001; I 2=90%) and shorter total colonoscopy time (MD -7.17 minutes; 95%CI [-9.10, -5.25]; P<0.00001; I 2=41%). No significant differences were observed in en bloc resection rate or immediate bleeding.

CONCLUSION

Hot snare polypectomy presents a slightly higher complete resection rate, but, as it is associated with a longer procedure time and a higher rate of delayed bleeding compared to Cold Snare, it cannot be recommended as the gold standard approach. Individual analysis and personal experience should be considered when selecting the best approach.

Establishment of a risk prediction model for bowel preparation failure prior to colonoscopy

BACKGROUND

This study aimed to determine the factors that contribute to the failure of bowel preparation in patients undergoing colonoscopy and to develop a risk prediction model.

METHODS

A total of 1115 outpatients were included. Patients were randomly divided into two groups: the modeling group (669 patients) and the validation group (446 patients). In the modeling group, patients were further divided into two groups based on their success and failure in bowel preparation using the Boston Bowel Preparation Scale. A logistic regression analysis model was used to determine the risk factors of bowel preparation failure, which was subsequently visualized using an alignment diagram.

RESULTS

After controlling for relevant confounders, multifactorial logistic regression results showed that age ≥ 60 years (OR = 2.246), male (OR = 2.449), body mass index ≥ 24 (OR = 2.311), smoking (OR = 2.467), chronic constipation (OR = 5.199), diabetes mellitus (OR = 5.396) and history of colorectal surgery (OR = 5.170) were influencing factors of bowel preparation failure. The area under the ROC curve was 0.732 in the modeling group and 0.713 in the validation group. According to the calibration plot, the predictive effect of the model and the actual results were in good agreement.

CONCLUSIONS

Age ≥ 60 years, male, body mass index ≥ 24, smoking, chronic constipation, diabetes mellitus, and history of colorectal surgery are independent risk factors for bowel preparation failure. The established prediction model has a good predictive efficacy and can be used as a simple and effective tool for screening patients at high risk for bowel preparation failure.

Effect of Body Mass Index on Cecal Intubation Time During Unsedated Colonoscopy: Variation Across the Learning Stages of an Endoscopist

BACKGROUND Body mass index (BMI) and endoscopists' experiences can be associated with cecal intubation time (CIT), but such associations are controversial. This study aimed to clarify the association between BMI and CIT during unsedated colonoscopy at 3 learning stages of a single endoscopist. MATERIAL AND METHODS A total of 1500 consecutive patients undergoing unsedated colonoscopy by 1 endoscopist at our department from December 11, 2020, to August 21, 2022, were reviewed. They were divided into 3 learning stages according to the number of colonoscopies performed by 1 endoscopist, including intermediate (501-1000 colonoscopies), experienced (1001-1500 colonoscopies), and senior stages (1501-2000 colonoscopies). Variables that significantly correlated with CIT were identified by Spearman rank correlation analyses and then included in multiple linear regression analysis. RESULTS Overall, 1233 patients were included. Among them, 392, 420, and 421 patients were divided into intermediate, experienced, and senior stages, respectively. Median CIT was 7.83, 6.38, and 5.58 min at intermediate, experienced, and senior stages, respectively (P.

Underwater versus conventional endoscopic mucosal resection for ≥10 mm sessile or flat colorectal polyps: A systematic review and meta-analysis

BACKGROUND AND AIM

Underwater endoscopic mucosal resection (UEMR) has been an emerging substitute for conventional EMR (CEMR). This systematic review and meta-analysis aimed at comparing the efficiency and safety of the two techniques for removing ≥10 mm sessile or flat colorectal polyps.

METHODS

PubMed, Cochrane Library and Embase databases were searched up to February 2023 to identify eligible studies that compared the outcomes of UEMR and CEMR. This meta-analysis was conducted on the en bloc resection rate, R0 resection rate, complete resection rate, procedure time, adverse events rate and recurrence rate.

RESULTS

Nine studies involving 1,727 colorectal polyps were included: 881 were removed by UEMR, and 846 were removed by CEMR. UEMR was associated with a significant increase in en bloc resection rate [Odds ratio(OR) 1.69, 95% confidence interval(CI) 1.36-2.10, p<0.00001, I2 = 33%], R0 resection rate(OR 1.52, 95%CI 1.14-2.03, p = 0.004, I2 = 31%) and complete resection rate(OR 1.67, 95%CI 1.06-2.62, p = 0.03, I2 = 0%) as well as a significant reduction in procedure time(MD ‒4.27, 95%CI ‒7.41 to ‒1.13, p = 0.008, I2 = 90%) and recurrence rate(OR 0.52, 95%CI 0.33-0.83, p = 0.006, I2 = 6%). Both techniques were comparable in adverse events rate.

CONCLUSION

UEMR can be a safe and efficient substitute for CEMR in removing ≥10 mm sessile or flat colorectal polyps. More studies verifying the advantages of UEMR over CEMR are needed to promote its application.

Hybrid resection versus conventional resection for laterally spreading lesions of the papilla

BACKGROUND AND AIMS

Although conventional hot snare resection (CR) of laterally spreading lesions of the major papilla (LSL-Ps) is effective, it can be associated with delayed bleeding in upward of 25% of cases. Given the excellent safety profile of cold snare polypectomy in the colorectum, we investigated the efficacy and safety of a novel hybrid resection (HR) technique for LSL-P management, consisting of hot snare papillectomy plus cold snare resection of the laterally spreading component.

METHODS

A prospective cohort of patients underwent HR in a tertiary referral center over 60 months until December 2022. This cohort was compared with a historical cohort of patients who underwent CR at the same institution over 120 months until August 2017. The primary outcomes were recurrence and bleeding.

RESULTS

Twenty patients underwent HR (14 female; mean age 65.2 ± 12.2 years). Median lesion size was 30 mm (interquartile range, 25.0-47.5 mm). Recurrent or residual adenoma (RRA) was greater with HR (58.8% [n = 10] vs 29.8% [n = 14]; P = .034). The odds ratio for recurrence was 3.6 times (95% CI, 1.2-11.0) higher with HR (P = .027). RRA was multifocal in 4 (40%) and had a composite RRA volume >10 mm in 7 (70%). The median number of procedures required to treat RRA was higher with HR (4 vs 1, P = .002). There was no difference between CR and HR for intraprocedural bleeding (41.1% [n = 23] vs 25% [n = 5]; P = .587) or delayed bleeding (25.0% vs 10.0%, P = .211). There were no perforations.

CONCLUSIONS

The novel HR technique for LSL-P management is associated with a high rate of RRA that is recalcitrant to treatment, without mitigating the risk of intraprocedural or delayed bleeding. Therefore, CR should remain the mainstay management option for treating patients with an LSL-P. (Clinical trial registration number: NCT02306603.).

Trends in Detection of Adenoma and Sessile Serrated Lesions Over a Decade in a Community-Based Healthcare System

INTRODUCTION

Adenoma detection rate (ADR) is an accepted benchmark for screening colonoscopy. Factors driving ADR and its relationship with sessile serrated lesions detection rate (SSLDR) over time remain unclear. We aim to explore patient, physician, and procedural influences on ADR and SSLDR trends.

METHODS

Using a large healthcare system in northern California from January 2010 to December 2020, a total of 146,818 screening colonoscopies performed by 33 endoscopists were included. ADR and SSLDR were calculated over time using natural language processing. Logistic regression was used to calculate the odd ratios of patient demographics, physician attributes, and procedural details over time.

RESULTS

Between 2010 and 2020, ADR rose from 19.4% to 44.4%, whereas SSLDR increased from 1.6% to 11.6%. ADR increased by 2.7% per year (95% confidence interval 1.9%-3.4%), and SSLDR increased by 1.0% per year (95% confidence interval 0.8%-1.2%). Higher ADR was associated with older age, male sex, higher body mass index, current smoker, higher comorbidities, and high-risk colonoscopy. By contrast, SSLDR was associated with younger age, female sex, white race, and fewer comorbidities. Patient and procedure characteristics did not significantly change over time ( P -interaction >0.05). Longer years in practice and male physician were associated with lower ADR and SSLDR in 2010, but significantly attenuated over time ( P -interaction <0.05).

DISCUSSION

Both ADR and SSLDR have increased over time. Patient and procedure factors did not significantly change over time. Male endoscopist and longer years in practice had lower initial ADR and SSLDR, but significantly lessened over time.

Endoclip combined with colonic transendoscopic enteral tubing: a new approach for managing iatrogenic colonoscopy perforation

BACKGROUND

Iatrogenic colonoscopy perforation (ICP) is a rare but most serious complication during colonoscopy investigation. However, endoscopic closure plays an important role in the dealing with ICP with the development of endoscopic techniques presently, there are still some portion of patients transferred to surgery.

METHODS

Once a perforation was detected, endoclips were used to closed the defect of the colon. Then a colonic TET was planted inside the colon. The terminal end of the TET was put proximally to or near the location of the perforation. Then gas and fluid was sucked out through the TET with a syringe every 4 h.

RESULTS

Three cases were treated with endoclip closure and colonic TET drainage. Case 1 was caused by urgent immediate perforation during routine colonoscopy, case 2 was delayed perforation after snare resection, and case 3 was ESD-related perforation. All patients got healed, no one transferred to surgery.

CONCLUSIONS

A combination of endoclip closure and colonic TET drainage might be an easy and potential method in the dealing with different types of ICP. This study may offer a novel paradigm for addressing endoscopy-related intestinal perforations.

Pseudo-submucosal tumor in the colon: seeing is believing

A 65-year-old woman was admitted to our hospital with complaints of lower abdominal pain. Her physical examination was unremarkable. The results of routine laboratory testing were within the normal limits. In addition, abdominal CT was normal. Colonoscopy showed a cecum submucosal tumor with a pale yellow surface. Endoscopic ultrasound revealed homogeneous hypoechoic lesions originated from submucosal layer. ESD was subsequently performed to remove the submucosal lesion. During the ESD procedure, fecal outflowed from appendix opening . Yellow fecal-like material was visible after submucosal incision. The trap electrocut surface uplift showed more fecal attachment on the lamina propria surface, and myolayer integrity after clean the fecal (Fig1c), The final pathology of the surface bulge suggested hyperplasia (Fig1d). Patients were discharged with relieved lower abdominal pain. The final diagnosis was submucosal fecalith mimicking a submucosal tumor, eventually leads to chronic appendicitis. Common causes of cecal submucosal tumor include neuroendocrine tumors, lipomas, etc. There was few report about fecalith mimicking a submucosal tumor. ERTA is currently an effective endoscopic method for treating appendicitis combined with fecalith blockage. To our knowledge, this is the first report on a case of cecum submucosal fecalith mimicking a submucosal tumor and was successfully removed using endoscopy.

Effect of Real-Time Computer-Aided Polyp Detection System (ENDO-AID) on Adenoma Detection in Endoscopists-in-Training: A Randomized Trial

BACKGROUND

The effect of computer-aided polyp detection (CADe) on adenoma detection rate (ADR) among endoscopists-in-training remains unknown.

METHODS

We performed a single-blind, parallel-group, randomized controlled trial in Hong Kong between April 2021 and July 2022 (NCT04838951). Eligible subjects undergoing screening/surveillance/diagnostic colonoscopies were randomized 1:1 to receive colonoscopies with CADe (ENDO-AID[OIP-1]) or not (control) during withdrawal. Procedures were performed by endoscopists-in-training with <500 procedures and <3 years' experience. Randomization was stratified by patient age, sex, and endoscopist experience (beginner vs intermediate level, <200 vs 200-500 procedures). Image enhancement and distal attachment devices were disallowed. Subjects with incomplete colonoscopies or inadequate bowel preparation were excluded. Treatment allocation was blinded to outcome assessors. The primary outcome was ADR. Secondary outcomes were ADR for different adenoma sizes and locations, mean number of adenomas, and non-neoplastic resection rate.

RESULTS

A total of 386 and 380 subjects were randomized to CADe and control groups, respectively. The overall ADR was significantly higher in the CADe group than in the control group (57.5% vs 44.5%; adjusted relative risk, 1.41; 95% CI, 1.17-1.72; P < .001). The ADRs for <5 mm (40.4% vs 25.0%) and 5- to 10-mm adenomas (36.8% vs 29.2%) were higher in the CADe group. The ADRs were higher in the CADe group in both the right colon (42.0% vs 30.8%) and left colon (34.5% vs 27.6%), but there was no significant difference in advanced ADR. The ADRs were higher in the CADe group among beginner (60.0% vs 41.9%) and intermediate-level (56.5% vs 45.5%) endoscopists. Mean number of adenomas (1.48 vs 0.86) and non-neoplastic resection rate (52.1% vs 35.0%) were higher in the CADe group.

CONCLUSIONS

Among endoscopists-in-training, the use of CADe during colonoscopies was associated with increased overall ADR. (ClinicalTrials.gov, Number: NCT04838951).

Clinical significance of abdominal computed tomography and colonoscopy in the evaluation of phlebosclerotic colitis

Clinical manifestations of phlebosclerotic colitis (PC) exhibit significant variability, necessitating diverse treatment strategies depending on disease severity. However, there is limited research exploring the relationship between imaging findings and disease severity. Hence, this retrospective study aimed to analyze the correlation between computed tomography (CT) findings, colonoscopic features, and disease severity. This study compared the abdominal CT characteristics, colonoscopy findings, and treatment modalities of 45 PC patients. CT images were assessed for the severity of mesenteric venous calcification, maximum colonic wall thickness, number of involved colonic segments, and presence of pericolic inflammation. Colonoscopic images were assessed for dark purple discoloration mucosa, erosive and ulcerative lesions, mucosal edema, luminal narrowing, and the number of involved colonic segments. In addition, patients were categorized into three groups: the observation (n = 15), medical treatment (n = 19), and operation (n = 11) groups. In CT images, a significant difference in pericolic inflammation (p = 0.039) was observed among groups. Further, significant differences in dark purple discoloration mucosa (p = 0.033), erosive or ulcerative lesions (p < 0.001), mucosal edema (p < 0.001), luminal narrowing (p = 0.012), and the number of involved colonic segments (p = 0.001) were observed in colonoscopy. Moreover, we found positive correlations between CT and colonoscopy features. In conclusion, CT manifestations and colonoscopy findings exhibited correlation with disease severity in PC. When limited to one diagnostic tool, observations from that tool can infer potential manifestations of the alternative tool.

Spatio-Temporal Feature Transformation Based Polyp Recognition for Automatic Detection: Higher Accuracy than Novice Endoscopists in Colorectal Polyp Detection and Diagnosis

BACKGROUND

Artificial intelligence represents an emerging area with promising potential for improving colonoscopy quality.

AIMS

To develop a colon polyp detection model using STFT and evaluate its performance through a randomized sample experiment.

METHODS

Colonoscopy videos from the Digestive Endoscopy Center of the First Affiliated Hospital of Anhui Medical University, recorded between January 2018 and November 2022, were selected and divided into two datasets. To verify the model's practical application in clinical settings, 1500 colonoscopy images and 1200 polyp images of various sizes were randomly selected from the test set and compared with the STFT model's and endoscopists' recognition results with different years of experience.

RESULTS

In the randomized sample trial involving 1500 colonoscopy images, the STFT model demonstrated significantly higher accuracy and specificity compared to endoscopists with low years of experience (0.902 vs. 0.809, 0.898 vs. 0.826, respectively). Moreover, the model's sensitivity was 0.904, which was higher than that of endoscopists with low, medium, or high years of experience (0.80, 0.896, 0.895, respectively), with statistical significance (P < 0.05). In the randomized sample experiment of 1200 polyp images of different sizes, the accuracy of the STFT model was significantly higher than that of endoscopists with low years of experience when the polyp size was ≤ 0.5 cm and 0.6-1.0 cm (0.902 vs. 0.70, 0.953 vs. 0.865, respectively).

CONCLUSIONS

The STFT-based colon polyp detection model exhibits high accuracy in detecting polyps in colonoscopy videos, with a particular efficiency in detecting small polyps (≤ 0.5 cm)(0.902 vs. 0.70, P < 0.001).

Comparison of the characteristics of the CF-H290I and PCF-Q260JI colonoscopes in non-sedated patients with a history of abdominal or pelvic surgery: a randomized controlled study

BACKGROUND AND AIM

The purpose of this randomized controlled study was to compare the characteristics of the CF-H290I (high-definition) colonoscope with those of the PCF-Q260JI (high-resolution) colonoscope in non-sedated patients with a history of abdominal or pelvic surgery in an effort to help endoscopists to select more effectively and objectively between the various colonoscopes.

METHODS

A total of 397 patients who underwent colonoscopy at the Affiliated Wuxi People's Hospital of Nanjing Medical University, between August 2022 and October 2022 were randomized to a CF-H290I group (n = 198) or a PCF-Q260JI group (n = 199) using a computer-generated allocation method. We compared the adenoma detection rate (ADR), patient satisfaction with the examination, discomfort associated with colonoscopy including abdominal distension and pain, cecal intubation time, and patient willingness to undergo colonoscopy in the future between the CF-H290I and PCF-Q260JI groups.

RESULTS

There was no statistically significant difference in the overall ADR between the CF-H290I and PCF-Q260JI groups (81 [40.9%] vs 63 [31.7%], Z = 3.674, P = 0.055). However, the ADRs in the transverse colon and left colon were significantly higher in the CF-H290I group (22 [11.1%] vs 6 [3.0%], Z = 9.588, P = 0.002 and 57 [28.8%] vs 37 [18.6%], Z = 5.212, P = 0.017, respectively). More sessile serrated lesions were detected in the CF-H290I group (52 [26.3] vs 30 [15.1%], Z = 7.579, P = 0.006). Patient satisfaction with colonoscopy was better in the PCF-Q260JI group (8.91 ± 1.09 vs 8.51 ± 1.44, t = -3.158, P < 0.01) with less likelihood of discomfort (23 [11.6%] vs 41 [20.7%], Z = 6.144, P = 0.013), The number of patients willing to undergo colonoscopy in the future was significantly greater in the PCF-Q260JI group (168 [84.4%] vs 149 [75.3%], Z = 5.186, P = 0.023). The cecal intubation time was significantly shorter in the CF-H290I group (256.09 ± 155.70 s vs 315.64 ± 171.64 s, P = 0.004). There were no complications such as perforation or bleeding in either group.

CONCLUSION

The CF-H290I and PCF-Q260JI colonoscopes each have advantages when used in patients with a history of abdominal or pelvic surgery. The CF-H290I has higher ADRs in the transverse and left colon whereas the PCF-Q260JI is less painful and better accepted by patients. This study was approved by the Clinical Research Ethics Committee of Wuxi People's Hospital and was registered in the Chinese Clinical Trial Registry (ChiCTR2200063092).

Adherence to endoscopic surveillance guidelines for patients with inflammatory bowel disease: An Australian cohort study

BACKGROUND AND AIM

Patients with inflammatory bowel disease have an increased risk of developing colorectal cancer as compared with the general population. Endoscopic surveillance to detect early dysplastic changes is advised by several published clinical guidelines, which provide recommendations as to the timing and performance of surveillance procedures. There is a paucity of data as to adherence with these guidelines in clinical practice.

METHODS

A longitudinal inception cohort study of all new patients diagnosed with inflammatory bowel disease across a service network of Australian hospitals between January 2005 and June 2014, with continuous follow-up in a gastroenterology clinic until December 31, 2022. Patients were included if they warranted surveillance according to the Australian guidelines. Adherence to guidelines and technical and quality measures were reported.

RESULTS

A total of 136 patients were included, and a total of 263 surveillance procedures were performed. Ninety-five patients (70%) had their first surveillance colonoscopy within the correct time interval. Fifty patients (37%) were completely adherent to guidelines with respect to timing of all surveillance procedure. The overall dysplasia detection rate for surveillance procedures was 10%. Chromoendoscopy was only performed in 16% of procedures.

CONCLUSIONS

Adherence to endoscopic surveillance guidelines with regard to timing of procedures and the utilization of chromoendoscopy is poor. Further clinician education, promotion of the surveillance guidelines and incorporation of chromoendoscopy training as part of the national colonoscopy training program may improve adherence to guidelines.

A combination of bowel wall thickness and submucosa index is useful for estimating endoscopic improvement in ulcerative colitis: external validation of the Kyorin Ultrasound Criterion

BACKGROUND

Endoscopic improvement (EI; a Mayo endoscopic subscore of 0 or 1) is considered a therapeutic target in ulcerative colitis (UC) treatment. The potential to estimate EI non-invasively is an advantage of intestinal ultrasound (IUS). In a previous study, we developed a new sonographic parameter, the submucosa index (SMI), calculated as the ratio of the submucosal thickness to bowel wall thickness (BWT), and reported that combining BWT and SMI results in a practical and promising criterion for estimating EI without color Doppler assessment. This study aimed to validate the EI estimation ability of our B mode-based criterion, the 'Kyorin Ultrasound Criterion for UC' (KUC-UC; BWT < 3.8 mm and SMI < 50%), using an external cohort.

METHODS

Patients with UC who underwent IUS and colonoscopy within 15 days without a treatment change between examinations were included. IUS findings, including BWT, SMI, and modified Limberg score for vascularity of the colon, were assessed.

RESULTS

Forty-four test pairs of IUS and colonoscopy examinations in a total of 122 colonic segments were analyzed. The KUC-UC showed positive predictive value (PPV) of 94.6% and negative predictive value (NPV) of 80.0% for EI. In comparison, PPV and NPV were 85.4% and 79.0%, respectively, for the common criterion BWT of < 3 mm, and 83.0% and 82.7% for the validated Milan Ultrasound Criteria (a score of ≤ 6.2).

CONCLUSIONS

External validation showed that the KUC-UC using only B mode findings without complicated calculations is a feasible and accurate sonographic criterion for estimating the EI of UC.

Factors associated with negative colonoscopy in participants with a positive faecal immunochemical test from the Danish Colorectal Cancer Screening Program - a population-based study

AIM

In the Danish Colorectal Cancer Screening Program (DCCSP), 37% of participants undergoing colonoscopy have a negative result with no obvious findings that can be attributed to a positive faecal immunochemical test (FIT). The aim of this work was to identify predictors for a negative colonoscopy in DCCSP participants with a positive FIT.

METHOD

We included 73 655 FIT-positive DCCSP participants using the Danish Colorectal Cancer Screening Database and linked their screening results with data from several other national health registers. We stratified participants by all predictors, and compared them using multivariate logistic regression analysis. Results are reported as odds ratios (ORs).

RESULTS

We found that having a condition linked to gastrointestinal bleeding, for example fissures, haemorrhoids and inflammatory bowel disease, was strongly associated with the probability of having a negative colonoscopy [OR 2.77 (95% CI 2.59, 2.96)]. FIT concentration was inversely related to the probability of a negative colonoscopy, the OR decreased steadily from 0.79 (95% CI 0.75, 0.83) in the 40-59 μg/g group, to 0.44 (95% CI 0.42, 0.46) in the ≥200 μg/g group. Women had a 1.64 (95% CI 1.59, 1.70) times higher probability of a negative colonoscopy than men.

CONCLUSION

Our findings indicate that baseline conditions linked to gastrointestinal bleeding are an associating factor with having a negative colonoscopy. The same is true for low FIT concentration and female sex. Further studies with similar findings could suggest that an incorporation of these factors into a personalized screening approach by differentiating between diagnostic modalities could improve the process for the participant while alleviating the health care system.

A non-aligned translation with a neoplastic classifier regularization to include vascular NBI patterns in standard colonoscopies

Polyp vascular patterns are key to categorizing colorectal cancer malignancy. These patterns are typically observed in situ from specialized narrow-band images (NBI). Nonetheless, such vascular characterization is lost from standard colonoscopies (the primary attention mechanism). Besides, even for NBI observations, the categorization remains biased for expert observations, reporting errors in classification from 59.5% to 84.2%. This work introduces an end-to-end computational strategy to enhance in situ standard colonoscopy observations, including vascular patterns typically observed from NBI mechanisms. These retrieved synthetic images are achieved by adjusting a deep representation under a non-aligned translation task from optical colonoscopy (OC) to NBI. The introduced scheme includes an architecture to discriminate enhanced neoplastic patterns achieving a remarkable separation into the embedding representation. The proposed approach was validated in a public dataset with a total of 76 sequences, including standard optical sequences and the respective NBI observations. The enhanced optical sequences were automatically classified among adenomas and hyperplastic samples achieving an F1-score of 0.86%. To measure the sensibility capability of the proposed approach, serrated samples were projected to the trained architecture. In this experiment, statistical differences from three classes with a ρ-value <0.05 were reported, following a Mann-Whitney U test. This work showed remarkable polyp discrimination results in enhancing OC sequences regarding typical NBI patterns. This method also learns polyp class distributions under the unpaired criteria (close to real practice), with the capability to separate serrated samples from adenomas and hyperplastic ones.

Review article: Advances in the management of lower gastrointestinal bleeding

BACKGROUND

Lower gastrointestinal bleeding (LGIB) is a common emergency with substantial associated morbidity and mortality. Elective colonoscopy plays an essential role in management, with an even more important role for radiology in the acute setting. Recent advances in the management of patients with LGIB warrant review as the management has recently evolved.

AIMS

To provide a comprehensive and updated overview of advances in the approach to patients with LGIB METHODS: We performed a comprehensive literature search to examine the current data for this narrative review supplemented by expert opinion.

RESULTS

The incidence of LGIB is increasing worldwide, partly related to an ageing population and the increasing use of antithrombotics. Diverticulosis continues to be the most common aetiology of LGIB. Pre-endoscopic risk stratification tools, especially the Oakland score, can aid appropriate patient triage. Adequate resuscitation continues to form the basis of management, while appropriate management of antithrombotics is crucial to balance the risk of worsening bleeding against increased cardiovascular risk. Radiological imaging plays an essential role in the diagnosis and treatment of acute LGIB, especially among unstable patients. Colonoscopy remains the gold-standard test for the elective management of stable patients.

CONCLUSIONS

The management of LGIB has evolved significantly in recent years, with a shift towards radiological interventions for unstable patients while reserving elective colonoscopy for stable patients. A multidisciplinary approach is essential to optimise the outcomes of patients with LGIB.

AGA Clinical Practice Update on Appropriate and Tailored Polypectomy: Expert Review

DESCRIPTION

In this Clinical Practice Update (CPU), we provide guidance on the appropriate use of different polypectomy techniques. We focus on polyps <2 cm in size that are most commonly encountered by the practicing endoscopist, including use of classification systems to characterize polyps and various polypectomy methods. We review characteristics of polyps that require complex polypectomy techniques and provide guidance on which types of polyps require more advanced management by a therapeutic endoscopist or surgeon. This CPU does not provide a detailed review of complex polypectomy techniques, such as endoscopic submucosal dissection, which should only be performed by endoscopists with advanced training.

METHODS

This expert review was commissioned and approved by the American Gastroenterological Association (AGA) Institute CPU Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership, and underwent internal peer review by the CPU Committee and external peer review through standard procedures of Clinical Gastroenterology and Hepatology. These Best Practice Advice statements were drawn from a review of the published literature and from expert opinion. Because systematic reviews were not performed, these Best Practice Advice statements do not carry formal ratings regarding the quality of evidence or strength of the presented considerations. BEST PRACTICE ADVICE 1: A structured visual assessment using high-definition white light and/or electronic chromoendoscopy and with photodocumentation should be conducted for all polyps found during routine colonoscopy. Closely inspect colorectal polyps for features of submucosally invasive cancer. BEST PRACTICE ADVICE 2: Use cold snare polypectomy for polyps <10 mm in size. Cold forceps polypectomy can alternatively be used for 1- to 3-mm polyps where cold snare polypectomy is technically difficult. BEST PRACTICE ADVICE 3: Do not use hot forceps polypectomy. BEST PRACTICE ADVICE 4: Clinicians should be familiar with various techniques, such as cold and hot snare polypectomy and endoscopic mucosal resection, to ensure effective, safe, and optimal resection of intermediate-size polyps (10-19 mm). BEST PRACTICE ADVICE 5: Consider using lifting agents or underwater endoscopic mucosal resection for removal of sessile polyps 10-19 mm in size. BEST PRACTICE ADVICE 6: Serrated polyps should be resected using cold resection techniques. Submucosal injection may be helpful for polyps >10 mm if margins cannot be well delineated. BEST PRACTICE ADVICE 7: Use hot snare polypectomy to remove pedunculated lesions >10 mm in size. BEST PRACTICE ADVICE 8: Do not routinely use clips to close resection sites for polyps <20 mm. BEST PRACTICE ADVICE 9: Refer patients with polyps to endoscopic referral centers in the context of size ≥20 mm, challenging polypectomy location, or recurrent polyp at a prior polypectomy site. BEST PRACTICE ADVICE 10: Tattoo lesions that may need future localization at endoscopy or surgery. Tattoos should be placed in a location that will not interfere with subsequent attempts at endoscopic resection. BEST PRACTICE ADVICE 11: Refer patients with nonpedunculated polyps with clear evidence of submucosally invasive cancer for surgical evaluation. BEST PRACTICE ADVICE 12: Understand the endoscopy suite's electrosurgical generator settings appropriate for polypectomy or postpolypectomy thermal techniques.

Artificial Intelligence-Assisted Colonoscopy in Real-World Clinical Practice: A Systematic Review and Meta-Analysis

INTRODUCTION

Artificial intelligence (AI) could minimize the operator-dependent variation in colonoscopy quality. Computer-aided detection (CADe) has improved adenoma detection rate (ADR) and adenomas per colonoscopy (APC) in randomized controlled trials. There is a need to assess the impact of CADe in real-world settings.

METHODS

We searched MEDLINE, EMBASE, and Web of Science for nonrandomized real-world studies of CADe in colonoscopy. Random-effects meta-analyses were performed to examine the effect of CADe on ADR and APC. The study is registered under PROSPERO (CRD42023424037). There was no funding for this study.

RESULTS

Twelve of 1,314 studies met inclusion criteria. Overall, ADR was statistically significantly higher with vs without CADe (36.3% vs 35.8%, risk ratio [RR] 1.13, 95% confidence interval [CI] 1.01-1.28). This difference remained significant in subgroup analyses evaluating 6 prospective (37.3% vs 35.2%, RR 1.15, 95% CI 1.01-1.32) but not 6 retrospective (35.7% vs 36.2%, RR 1.12, 95% CI 0.92-1.36) studies. Among 6 studies with APC data, APC rate ratio with vs without CADe was 1.12 (95% CI 0.95-1.33). In 4 studies with GI Genius (Medtronic), there was no difference in ADR with vs without CADe (RR 0.96, 95% CI 0.85-1.07).

DISCUSSION

ADR, but not APC, was slightly higher with vs without CADe among all available real-world studies. This difference was attributed to the results of prospective but not retrospective studies. The discrepancies between these findings and those of randomized controlled trials call for future research on the true impact of current AI technology on colonoscopy quality and the subtleties of human-AI interactions.

Impact of computer-aided characterization for diagnosis of colorectal lesions, including sessile serrated lesions: Multireader, multicase study

OBJECTIVES

Computer-aided characterization (CADx) may be used to implement optical biopsy strategies into colonoscopy practice; however, its impact on endoscopic diagnosis remains unknown. We aimed to evaluate the additional diagnostic value of CADx when used by endoscopists for assessing colorectal polyps.

METHODS

This was a single-center, multicase, multireader, image-reading study using randomly extracted images of pathologically confirmed polyps resected between July 2021 and January 2022. Approved CADx that could predict two-tier classification (neoplastic or nonneoplastic) by analyzing narrow-band images of the polyps was used to obtain a CADx diagnosis. Participating endoscopists determined if the polyps were neoplastic or not and noted their confidence level using a computer-based, image-reading test. The test was conducted twice with a 4-week interval: the first test was conducted without CADx prediction and the second test with CADx prediction. Diagnostic performances for neoplasms were calculated using the pathological diagnosis as reference and performances with and without CADx prediction were compared.

RESULTS

Five hundred polyps were randomly extracted from 385 patients and diagnosed by 14 endoscopists (including seven experts). The sensitivity for neoplasia was significantly improved by referring to CADx (89.4% vs. 95.6%). CADx also had incremental effects on the negative predictive value (69.3% vs. 84.3%), overall accuracy (87.2% vs. 91.8%), and high-confidence diagnosis rate (77.4% vs. 85.8%). However, there was no significant difference in specificity (80.1% vs. 78.9%).

CONCLUSIONS

Computer-aided characterization has added diagnostic value for differentiating colorectal neoplasms and may improve the high-confidence diagnosis rate.

Detection of high-risk polyps at screening colonoscopy indicates risk for liver and biliary cancer death

BACKGROUND

Hepatobiliary cancers share risk factors with colorectal cancer (CRC), but there are no combined screening programs for these conditions.

AIMS

The aim of this study was to assess whether patients with high-risk colonic polyps are more likely to die from liver related tumors than patients with a negative colonoscopy.

METHODS

In this retrospective analysis of mortality data, Austrian screening participants were included. The absolute risk for hepatobiliary cancer death was calculated using the cumulative incidence method. We aimed to identify an association with time to death of hepatobiliary cancer by Cox proportional hazards model.

RESULTS

343,838 colonoscopies performed between 01/2007 and 12/2020 were included in the analysis, of which 17,678 (5.14%) revealed high-risk polyps. Overall hepatobiliary cancer mortality was more than twice as high in patients with high risk polyps (cumulative incidence 0.39%, 95% CI 0.37-0.41%) compared to patients with a negative colonoscopy (cumulative incidence 0.17%, 95% CI 0.17-0.17%). When adjusting for age and sex, having high-risk polyps at screening colonoscopy was significantly associated with hepatobiliary cancer death (HR 1.83, 95% CI 1.29- 2.59, p < 0.001).

CONCLUSIONS

Patients with certain colonic polyp characteristics are at increased risk for mortality of liver malignancies. Further studies are needed to determine whether a structured additional screening for liver diseases and consecutive malignancies might be beneficial in these patients.

Detection of sessile serrated adenoma using artificial intelligence-enhanced endoscopy: an Asian perspective

BACKGROUND

As the serrated pathway has gained prominence as an alternative colorectal carcinogenesis pathway, sessile serrated adenomas or polyps (SSA/P) have been highlighted as lesions to rule out during colonoscopy. These lesions are however morphologically difficult to detect on endoscopy and can be mistaken for hyperplastic polyps due to similar endoscopic features. With the underlying nature of rapid progression and malignant transformation, interval cancer is a likely consequence of undetected or overlooked SSA/P. Real-time artificial intelligence (AI)-assisted colonoscopy via the computer-assisted detection system (CADe) is an increasingly useful tool in improving adenoma detection rate by providing a second eye during the procedure. In this article, we describe a guide through a video to illustrate the detection of SSA/P during AI-assisted colonoscopy.

METHODS

Consultant-grade endoscopists utilized real-time AI-assisted colonoscopy device, as part of a larger prospective study, to detect suspicious lesions which were later histopathologically confirmed to be SSA/P.

RESULTS

All lesions were picked up by the CADe where a real-time green box highlighted suspicious polyps to the clinician. Three SSA/P of varying morphology are described with reference to classical SSA/P features and with comparison to the features of the hyperplastic polyp found in our study. All three SSA/P observed are in keeping with the JNET Classification (Type 1).

CONCLUSION

In conclusion, CADe is a most useful aid to clinicians during endoscopy in the detection of SSA/P but must be complemented with factors such as good endoscopy skill and bowel prep for effective detection, and biopsy coupled with subsequent accurate histological diagnosis.

Geometry of cold snare polypectomy and risk of incomplete resection

BACKGROUND

Cold snare polypectomy (CSP) is safer than and equally efficacious as hot snare polypectomy (HSP) for the removal of small (<10mm) colorectal polyps. The maximum polyp size that can be effectively managed by piecemeal CSP (p-CSP) without an excessive burden of recurrence is unknown.

METHODS

Resection error risks (RERs), defined as the estimated likelihood of incomplete removal of adenomatous tissue for a single snare resection pass, for CSP and HSP were calculated, based on an incomplete resection rate. Polyp area, snare size, estimated number of resections, and optimal resection defect area were modeled. Overall risk of incomplete resection (RIR) was defined as RIR=1 - (1 - p)n, where p is the RER and n the number of resections.

RESULTS

A 40-mm polyp has a four times greater area than a 20-mm polyp (314.16mm2 vs. 1256.64mm2), and requires three times more resections (11 vs. 33, respectively, assuming 8-mm piecemeal resection pieces for p-CSP). RIRs for a 40-mm polyp by HSP and p-CSP were 15.1%-23% and 40.74%-60.60% respectively.

CONCLUSION

RER is more important with p-CSP than with HSP. The number of resections, n, and consequently RIR increases with increasing polyp size. Given the overwhelming safety of CSP, specific techniques to minimize the RER should be studied and developed.

Endoscopy in pediatric polyposis syndromes: why, when and how

Single or multiple polyps are frequently encountered during colonoscopy among children and adolescents and may be indicative of hereditary polyposis syndrome (HPS). The management of children with single or multiple polyps is guided by the number of polyps, their distribution and the histological findings. Children with HPS carry a high risk of complications, including intestinal and extra-intestinal malignancies. The goals of surveillance in pediatric HPS are to treat symptoms, monitor the burden of polyps and prevent short- and long-term complications. Therefore, the management of children with HPS is based on therapeutic endoscopy. The strategy of therapeutic endoscopy is a careful assessment and characterization of the polyps and performing polypectomies using advanced endoscopic techniques. A multidisciplinary approach, comprising clinical, interventional endoscopy, cancer surveillance and support of familial and emotional aspects is essential in the management of children with HPS.

Snare Tip Soft Coagulation vs Argon Plasma Coagulation vs No Margin Treatment After Large Nonpedunculated Colorectal Polyp Resection: a Randomized Trial

BACKGROUND & AIMS

Thermal treatment of the defect margin after endoscopic mucosal resection (EMR) of large nonpedunculated colorectal lesions reduces the recurrence rate. Both snare tip soft coagulation (STSC) and argon plasma coagulation (APC) have been used for thermal margin treatment, but there are few data directly comparing STSC with APC for this indication.

METHODS

We performed a randomized 3-arm trial in 9 US centers comparing STSC with APC with no margin treatment (control) of defects after EMR of colorectal nonpedunculated lesions ≥15 mm. The primary end point was the presence of residual lesion at first follow-up.

RESULTS

There were 384 patients and 414 lesions randomized, and 308 patients (80.2%) with 328 lesions completed ≥1 follow-up. The proportion of lesions with residual polyp at first follow-up was 4.6% with STSC, 9.3% with APC, and 21.4% with control subjects (no margin treatment). The odds of residual polyp at first follow-up were lower for STSC and APC when compared with control subjects (P = .001 and P = .01, respectively). The difference in odds was not significant between STSC and APC. STSC took less time to apply than APC (median, 3.35 vs 4.08 minutes; P = .019). Adverse event rates were low, with no difference between arms.

CONCLUSIONS

In a randomized trial STSC and APC were each superior to no thermal margin treatment after EMR. STSC was faster to apply than APC. Because STSC also results in lower cost and plastic waste than APC (APC requires an additional device), our study supports STSC as the preferred thermal margin treatment after colorectal EMR. (Clinicaltrials.gov, Number NCT03654209.).

Improving the management and outcomes of complex non-pedunculated colorectal polyps at a regional hospital in British Columbia

BACKGROUND

Colorectal cancer arises from precancerous lesions, primarily adenomatous and serrated polyps. Some polyps pose significant technical endoscopic challenges due to their size, location, and/or morphology. A standardized protocol for documentation and management of these polyps can optimize clinical outcomes.

METHODS

A Quality Improvement project compared patients with a complex polyp (non-pedunculated, > 2 cm), for 12 months prior and 12 months after protocol introduction. Documentation and polyp management details were compared pre- and post-implementation using the Chi-square test.

RESULTS

69 patients were diagnosed with complex polyps prior to the protocol introduction and 72 after. 79% (112/141) of patients underwent endoscopic mucosal resections (EMR) locally, and 14.9% (21/141) underwent surgery locally. After protocol introduction, there was significant improvement in documentation of suspicious appearing polyps (21.7% to 47.2%, P = 0.001), luminal circumference (14.5% to 34.7%, P = 0.005), and management plans (87.0% to 97.2%, P = 0.023); other elements of documentation were similar. The number of patients reviewed at multidisciplinary conference (MDC) increased from 1 to 61% (P < 0.005). Patients rebooked in a 1 h endoscopy time slot increased from 19 to 58% (P < 0.005), as did specific consent for EMR from 22 to 57% (P < 0.005). Among patients with polyps 3 cm or greater (23 pre, 36 post), MDC review increased from 4 to 67% (P < 0.005), primary polypectomy decreased from 72 to 23% (P = 0.001), patients rebooked in a double endoscopy slot increased from 33 to 75% (P = 0.005), and specific consent increased from 39 to 75% (P = 0.014). There were less polyp recurrences (12/42 pre and 1/50 post) among the post-protocol cohort (P < 0.001).

CONCLUSIONS

The introduction of a formalized protocol for complex polyp adjudication and management has led to improved documentation, multidisciplinary discussion, and optimal complex polyp management with dedicated time for EMR, particularly for polyps over 3 cm. There is room for improvement, and this can be approached in a collaborative manner.

Analyzing methods for reducing recurrence rates after EMR of large nonpedunculated colorectal polyps: an indirect pairwise comparison

BACKGROUND AND AIMS

Despite advances in EMR techniques, a high polyp recurrence rate remains a challenge. Due to the scarcity of direct comparisons, we performed an indirect comparison of conventional EMR (EMR alone), underwater EMR (U-EMR), and EMR + adjuvant thermal ablation of polypectomy margins to assess polyp recurrence rates.

METHODS

Electronic databases were searched from inception to January 12, 2023, for studies reporting polyp recurrence rates after EMR for large nonpedunculated polyps (>15 mm) with or without adjuvant techniques (snare tip soft coagulation [STSC]/argon plasma coagulation [APC]). An indirect comparison was performed by using the frequentist method. The p-score was calculated to identify preferred intervention. Publication bias was assessed by using a comparison-adjusted funnel plot.

RESULTS

A total of 9 full articles were identified. On direct comparisons, EMR + STSC had 82% reduced odds (odds ratio, .18; 95% confidence interval, .13-.26; P < .001), whereas U-EMR alone had 77% reduced odds (odds ratio, .23; 95% confidence interval, .08-.67; P = .007) of polyp recurrence compared with EMR alone. On indirect comparison, all interventions had significantly lower odds of polyp recurrence compared with EMR alone. The p-score ranking showed that EMR + STSC seems a potential first method in reducing the odds of polyp recurrence, followed by U-EMR, EMR + APC, and EMR alone.

CONCLUSIONS

EMR + STSC seems to provide favorable odds for reducing polyp recurrence postresection for large nonpedunculated polyps. Standardization of methods to detect residual polyp and prevent polyp recurrence at the time of EMR are required.