Management of complex polyps of the colon and rectum

In vivo evaluation of complex polyps with endoscopic optical coherence tomography and deep learning during routine colonoscopy: a feasibility study

Standard-of-care (SoC) imaging for assessing colorectal polyps during colonoscopy, based on white-light colonoscopy (WLC) and narrow-band imaging (NBI), does not have sufficient accuracy to assess the invasion depth of complex polyps non-invasively during colonoscopy. We aimed to evaluate the feasibility of a custom endoscopic optical coherence tomography (OCT) probe for assessing colorectal polyps during routine colonoscopy. Patients referred for endoscopic treatment of large colorectal polyps were enrolled in this pilot clinical study, which used a side-viewing OCT catheter developed for use with an adult colonoscope. OCT images of polyps were captured during colonoscopy immediately before SoC treatment. A deep learning model was trained to differentiate benign from deeply invasive lesions for real-time diagnosis. 35 polyps from 32 patients were included. OCT imaging added on average 3:40 min (range 1:54-8:20) to the total procedure time. No complications due to OCT were observed. OCT revealed distinct subsurface tissue structures that correlated with histological findings, including tubular adenoma (n = 20), tubulovillous adenoma (n = 10), sessile serrated polyps (n = 3), and invasive cancer (n = 2). The deep learning model achieved an area under the receiver operating characteristic curve (AUROC) of 0.984 (95%CI 0.972-0.996) and Cohen's kappa of 0.845 (95%CI 0.774-0.915) when compared to gold standard histopathology. OCT is feasible and safe for polyp assessment during routine colonoscopy. When combined with deep learning, OCT offers clinicians increase confidence in identifying deeply invasive cancers, potentially improving clinical decision-making. Compared to previous studies, ours offers a nuanced comparison between not just benign and malignant lesions, but across multiple histological subtypes of polyps.

Colonoscopic-assisted laparoscopic wedge resection for colonic neoplasms: a systematic review

OBJECTIVES

The current literature describes a variety of techniques detailed under the name of combined endoscopic-laparoscopic surgery (CELS) procedures. This systematic review of literature assessed the outcomes of colonoscopic-assisted laparoscopic-wedge resection (CAL-WR) in particular to evaluate its feasibility to remove colonic lesions that do not qualify for endoscopic resection.

MATERIALS AND METHODS

Electronic databases (PubMed, Embase, and Cochrane) were searched for studies evaluating CAL-WR for the treatment of colonic lesions. Studies with missing full text, language other than English, systematic reviews, and studies with fewer than ten patients were excluded. The quality of the studies was assessed using the Newcastle-Ottawa Scale.

RESULTS

Out of 68 results, duplicate studies (n = 27) as well as studies that did not meet the inclusion criteria (n = 32) were removed. Nine studies were included, encompassing 326 patients who underwent a CAL-WR of the colon. The technical success rate varied from 93 to 100%, with an R0 resection rate of 91-100%. Morbidity ranged from 6% to 20%. The quality of the included studies was rated as low to moderate and contained heterogeneous terminology, methodology, and outcome measures.

CONCLUSIONS

There is insufficient high-quality data and substantial variation in outcome measures to draw firm conclusions regarding the value of CAL-WR. Although CAL-WR is a promising local resection technique for endoscopically unremovable neoplasms of the colon, further investigation of this technique in well-designed prospective, multicenter studies with predefined outcome measures is required.Trial registration: A protocol for this systematic review was registered in PROSPERO with the number CRD42023407966.

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.

Colonoscopic-assisted laparoscopic wedge resection versus segmental colon resection for benign colonic polyps: a comparative cost analysis

AIM

The colonoscopic-assisted laparoscopic wedge resection (CAL-WR) is proven to be an effective and safe alternative to a segmental colon resection (SCR) for large or complex benign colonic polyps that are not eligible for endoscopic removal. This analysis aimed to evaluate the costs of CAL-WR and compare them to the costs of an SCR.

METHOD

A single-centre 90-day 'in-hospital' comparative cost analysis was performed on patients undergoing CAL-WR or SCR for complex benign polyps between 2016 and 2020. The CAL-WR group consisted of 44 patients who participated in a prospective multicentre study (LIMERIC study). Inclusion criteria were (1) endoscopically unresectable benign polyps; (2) residual or recurrence after previous polypectomy; or (3) irradically resected low risk pT1 colon carcinoma. The comparison group, which was retrospectively identified, included 32 patients who underwent an elective SCR in the same period.

RESULTS

Colonoscopic-assisted laparoscopic wedge resection was associated with significantly fewer complications (7% in the CAL-WR group vs. 45% in the SCR group, P < 0.001), shorter operation time (50 min in the CAL-WR group vs. 119 min in the SCR group, P < 0.001), shorter length of hospital stay (median length of stay 2 days in the CAL-WR group vs. 4 days in the SCR group, P < 0.001) and less use of surgical resources (reduction in costs of 32% per patient), resulting in a cost savings of €2372 (£2099 GBP) per patient (P < 0.001).

CONCLUSION

Given the clinical and financial benefits, CAL-WR should be recommended for complex benign polyps that are not eligible for endoscopic resection before major surgery is considered.

The effectiveness of walking exercise on the bowel preparation before colonoscopy: a single blind randomized clinical trial study

BACKGROUND AND AIM

Bowel preparation is a crucial factor affecting the diagnostic accuracy of colonoscopy, and few randomized control trials evaluated enhancement in bowel preparation. In this study, we aimed to evaluate the effectiveness of walking exercises on bowel preparation before a colonoscopy procedure.

METHODS

The present study is a single-blind randomized controlled trial involving 262 patients scheduled for colonoscopy procedures. These patients were randomly assigned to two groups: an intervention group (n = 131) and a control group (n = 131). In the intervention group, participants followed a predetermined plan that included the consumption of specific liquids and foods, bisacodyl pills, polyethylene glycol powder, and a regimen of walking exercises in preparation for their colonoscopy. Conversely, individuals in the control group followed the same regimen but were not instructed to engage in walking exercises. On the day of the colonoscopy, both groups were assessed for their level of physical activity using a foot counter. Additionally, an experienced gastroenterologist evaluated and compared the bowel preparation between the two groups using the Boston Bowel Preparation Scale (BBPS).

RESULTS

The number of footsteps recorded in the two groups exhibited a significant difference (P < 0.001). Although there was no statistically significant difference between the intervention and control groups in terms of mean BBPS scores (6.26 ± 1.9 vs. 6.29 ± 1.9, P = 0.416), individuals who took more than 6900 steps had significantly higher BBPS scores compared to those with fewer than 6900 footsteps (6.62 ± 1.8 vs. 5.92 ± 1.9, P = 0.003).In the univariate analysis, BBPS was found to be significantly associated with individuals under the age of 50 (OR: 2.45, 95% CI: 1.30-4.61, P = 0.006) and smoking status (OR: 0.41, 95% CI: 0.17-0.94, P = 0.043). In the multivariate analysis, the relationship between BBPS and age below 50 and smoking remained significant (OR: 2.50, 95% CI: 1.30-4.70, P = 0.005, and OR: 0.38, 95% CI: 0.16-0.93, P = 0.034, respectively).

CONCLUSION

A higher number of footsteps taken especially more than 6900 can significantly enhance bowel preparation; however, walking exercise as an intervention before colonoscopy is not significantly associated with BBPS. Also, older people and smokers seem to have fewer benefits from walking exercises for bowel preparation.

TRIAL REGISTRATION

ISRCTN32724024 (Registration date:22/08/2018).

Endoscopic mucosal resection of gastrointestinal polyps with a novel low-temperature plasma radio frequency generator: a non-inferiority multi-center randomized control study

BACKGROUND

To evaluate the efficacy and safety of novel plasma radio frequency generator and its single-use polypectomy snares for endoscopic mucosal resection (EMR) of gastrointestinal (GI) polyps.

METHODS

A total of 217 patients with 413 GI polyps were recruited from four centers in China. Patients were assigned to experimental or control groups using a central randomization method. The experimental group used the novel plasma radio frequency generator and its matched single-use polypectomy snares (Neowing, Shanghai), while the control group used the high-frequency electrosurgical unit (Erbe, Germany) and disposable electrosurgical snares (Olympus, Japan). The primary endpoint was the en bloc resection rate, and the non-inferiority margin was set at 10%. Secondary endpoint included operation time, coagulation success rate, intraoperative and postoperative bleeding rate, and perforation rate.

RESULTS

The en bloc resection rate was 97.20% (104/107) in the experimental group and 95.45% (105/110) in the control group (P = 0.496). The operation time was 29.14 ± 20.21 min in the experimental group and 30.26 ± 18.74 min in the control group (P = 0.671). The average removal time of a single polyp in the experimental group was 7.52 ± 4.45 min, which was slightly shorter than that in the control group 8.90 ± 6.67 min, with no statistical difference (P = 0.076). The intraoperative bleeding rates of the experimental group and control group were 8.41% (9/107) and 10.00% (11/110), respectively (P = 0.686). No intraoperative perforation occurred in either group. The postoperative bleeding rates of the experimental group and the control group were 1.87% (2/107) and 4.55% (5/110), respectively (P = 0.465). No postoperative perforation occurred in the experimental group (0/107), while one case of delayed perforation occurred in the control group (1/110, 0.91%). There was no statistical difference between the two groups.

CONCLUSIONS

Endoscopic mucosal resection of GI polyps with the novel plasma radio frequency generator is safe and effective, and non-inferior to the conventional high-frequency electrosurgical system.

Participants' experiences of the management of screen-detected complex polyps within a structured bowel cancer screening programme

Background

The Bowel Screening Wales complex polyp removal service was introduced to address variations in surgery rates for screen‐detected complex benign colorectal polyps, to improve the quality of the screening service and to make management of these polyps more equitable across Wales. Little is known about patient experiences and the potential impact on quality of life when undergoing complex polyp removal. This study is part of a wider research programme evaluating the decision‐making, pathways and outcomes from complex polyp removal.

Objective

This study aimed to understand experiences of having a complex polyp removed and how this may influence quality of life.

Design

Semi‐structured telephone interviews were conducted, and a thematic approach was used for data analysis.

Setting and Participants

All participants had a complex polyp removed after a positive stool test and review by Bowel Screening Wales' Network Multi‐Disciplinary Team.

Results

Twenty‐one participants were interviewed. Most participants had their complex polyps removed endoscopically and reported no or minor problems or negative outcomes following their procedure. For a small minority, worse problems (e.g., pain, bowel dysfunction) and negative outcomes (e.g., cancer) followed their procedures. Most participants felt supported and reassured throughout their procedures. Any physical and emotional changes to quality of life were mainly linked to procedure outcomes.

Discussion

Experiences of complex polyp removal were generally positive, with minimal changes in quality of life.

Conclusions

While most people had a positive experience of having a complex polyp removed, support initiatives, such as counselling or signposting to coping strategies, may be helpful to reduce any potential negative effects of procedures on quality of life.

Patient or Public Contribution

Four patient and public involvement partners provided feedback on participant materials.

[Clinical features of intestinal polyps and risk factors for secondary intussusception in children: an analysis of 2 669 cases]

OBJECTIVES

To study the clinical features of intestinal polyps and the risk factors for secondary intussusception in children.

METHODS

A retrospective analysis was performed for the medical data of 2 669 children with intestinal polyps. According to the presence or absence of secondary intussusception, they were divided into two groups: intussusception (n=346) and non-intussusception (n=2 323). Related medical data were compared between the two groups. The multivariate logistic regression analysis was used to identify the risk factors for secondary intussusception.

RESULTS

Among the children with intestinal polyps, 62.42% were preschool children, and the male/female ratio was 2.08∶1; 92.66% had hematochezia as disease onset, and 94.34% had left colonic polyps and rectal polyps. There were 346 cases of secondary intussusception, with an incidence rate of 12.96% (346/2 669). Large polyps (OR=1.644, P<0.001), multiple polyps (≥2) (OR=6.034, P<0.001), and lobulated polyps (OR=93.801, P<0.001) were the risk factors for secondary intussusception.

CONCLUSIONS

Intestinal polyps in children often occur in preschool age, mostly in boys, and most of the children have hematochezia as disease onset, with the predilection sites of the left colon and the rectum. Larger polyps, multiple polyps, and lobulated polyps may increase the risk of secondary intussusception, and endoscopic intervention is needed as early as possible to improve prognosis.

Multidisciplinary decision-making strategies may reduce the need for secondary surgery in complex colonic polyps - A systematic review and pooled analysis

AIM

The recognition of complex colonic polyps is increasing. Management varies considerably and the impact of this on clinical outcomes is unclear. The aim of this systematic review was to assess the impact of group decision-making strategies and defined selection criteria on the treatment outcomes of complex colonic polyps.

METHOD

A systematic literature review identified studies reporting complex polyp treatment outcomes and describing their decision-making strategies. Databases searched included PubMed, Web of Science, CINAHL and Scopus. Articles were identified by two blinded reviewers using defined inclusion criteria. The review protocol was registered on PROSPERO and performed in line with PRISMA guidelines.

RESULTS

There were 303 identified articles describing treatment outcomes of complex colonic polyps. Only nine of these fully described the decision-making strategy and met the inclusion criteria. Adverse events ranged from 1.3% to 10% across the studies. Unsuspected malignancy and secondary surgery rates ranged from 2.4% to 15.4% and 3.3% to 43.9%, respectively. Grouping of articles into a hierarchy of decision-making strategies demonstrated a sequential reduction in secondary surgery rates with improving strategies. There were no differences in comparisons of adverse event or unsuspected malignancy rates.

CONCLUSIONS

There is limited description of decision-making strategies and variability in reporting of studies describing complex polyp treatment outcomes. The use of multidisciplinary decision-making and defined selection criteria may reduce the need for secondary surgical intervention in complex colonic polyps, but further evidence is required to draw definite conclusions.

Prediction of technically difficult endoscopic submucosal dissection for large superficial colorectal tumors: a novel clinical score model

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is a promising technique for removing superficial GI tumors, but ESD is technically difficult. The aim of this study was to establish a clinical score model for grading technically difficult colorectal ESD.

METHODS

Data on patients, lesions, and outcomes of colorectal ESD at 2 centers were analyzed. The objective parameter of successful ESD within 60 minutes was set as an endpoint to evaluate the difficulty. Independent predictors of difficulty in the derivation cohort were identified by multiple logistic regression analysis and used to develop a clinical score. We validated the score model in the validation cohort.

RESULTS

The clinical score comprised tumor size of 30 to 50 mm (1 point) or ≥50 mm (2 points), at least two-thirds circumference of the lesion (2 points), location in the cecum (1 point), flexure (2 points) or dentate line (1 point), and laterally spreading tumor nongranular lesions (1 point). Areas under the receiver operator characteristic curves for the score model were comparable (derivation [.70] vs internal validation [.69] vs external validation [.69]). The probability of successful ESD within 60 minutes in easy (score = 0), intermediate (score = 1), difficult (score = 2-3), and very difficult (score ≥4) categories were 75.0%, 51.3%, 35.6%, and 3.4% in the derivation cohort; 73.3%, 47.9%, 31.8%, and 16.7% in the internal validation cohort; and 79.5%, 66.7%, 43.3%, and 20.0% in the external validation cohort, respectively.

CONCLUSIONS

This clinical score model accurately predicts the probability of successful ESD within 60 minutes and can be applied to grade the technical difficulty before the procedure.

Oncological outcome after local treatment for early stage rectal cancer

BACKGROUND

Treatment of early rectal cancer is evolving towards organ-preserving therapy which includes endoscopic resection and transanal approaches. We aimed to explore the role of local treatments such as endoscopic polypectomy (Endoscopic Mucosal Resection (EMR) or Endoscopic submucosal dissection (ESD)) and transanal endoscopic microsurgery/ transanal minimal invasive surgery (TEM/TAMIS) in patients who had early rectal cancer. We considered these outcomes alongside conventional major surgery using total mesorectal excision (TME) for early stage disease.

METHODS

All patients identified at MDT with early stage rectal cancer at our institution between 2010 and 2019 were included. Long-term outcomes in terms of local recurrence, survival and procedure-specific morbidity were analysed.

RESULTS

In total, 536 patients with rectal cancer were identified, of which 112 were included based on their pre-operative identification at the MDT on the basis that they had node-negative early rectal cancer. Among these, 30 patients (27%) had the lesion excised by flexible endoscopic polypectomy techniques (EMR/ESD), 67 (60%) underwent TEM/TAMIS and 15 (13%) had major surgery. There were no differences in patient demographics between the three groups except for TEM/TAMIS patients being more likely to be referred from another hospital (p < 0.001) and they were less active (WHO performance status p = 0.04). There were no significant differences in overall survival rates and cancer-specific survival between the three treatment groups. The 5-year overall survival rate for endoscopic polypectomy, TEM/TAMIS or major resection was 96% versus 90% and 88%, respectively (p = 0.89). The 5- year cancer-specific survival rate was 96%, versus 96% and 100%, respectively (p = 0.74).

CONCLUSION

Endoscopic polypectomy by EMR/ESD is an appropriate local treatment for early stage rectal cancer in selected patients. It is possible to achieve good oncological outcomes with a polypectomy similar to TEM/TAMIS and major surgery; however, a multidisciplinary approach is necessary enabling close surveillance and the use of adjuvant radiotherapy.

Wnt/β‑catenin signaling: Causes and treatment targets of drug resistance in colorectal cancer (Review)

Colorectal cancer (CRC) is the third most common malignant tumor in humans. Chemotherapy is used for the treatment of CRC. However, the effect of chemotherapy remains unsatisfactory due to drug resistance. Growing evidence has shown that the presence of highly metastatic tumor stem cells, regulation of non-coding RNAs and the tumor microenvironment contributes to drug resistance mechanisms in CRC. Wnt/β-catenin signaling mediates the chemoresistance of CRC in these three aspects. Therefore, the present study analyzed the abundant evidence of the contribution of Wnt/β-catenin signaling to the development of drug resistance in CRC and discussed its possible role in improving the chemosensitivity of CRC, which may provide guidelines for its clinical treatment.

Feasibility and learning curve of unsupervised colorectal endoscopic submucosal hydrodissection at a Western Center

OBJECTIVES

Colorectal endoscopic submucosal dissection (CR-ESD) is an evolving technique in Western countries. We aimed to determine the results of the untutored implementation of endoscopic submucosal hydrodissection for the treatment of complex colorectal polyps and establish the learning curve for this technique.

METHODS

This study included data from 80 consecutive CR-ESDs performed by a single unsupervised western therapeutic endoscopist. To assess the learning curve, procedures were divided into four groups of 20 each.

RESULTS

En bloc resection was achieved in 55, 75, 75 and 95% cases in the consecutive time periods (period 1 vs. 4, P = 0.003). Curative resection was achieved in 55, 75, 70 and 95%, respectively (P = 0.037). Overall, series results demonstrated R0 resection in 75% of cases, with 23.7% requiring conversion to endoscopic piecemeal mucosal resection, and 1.25% incomplete resections. Complications included perforations (7.5%) and bleeding (3.7%). Multivariate analysis revealed factors more likely to result in association with non en bloc vs. En bloc resection, where polyp size ≥35 mm [70 vs. 23.4%; odds ratio (OR) 13.2 (1.7-100.9); P = 0. 013], severe fibrosis [40 vs. 11.7%; OR 10.2 (1.2-86.3); P = 0.033] and where carbon dioxide for insufflation was not used [65 vs. 30%; OR 0.09 (0.01-0.53); P = 0.008].

CONCLUSION

CR-ESD by hydrodissection has good safety and efficacy profile and offers well tolerated and effective treatment for complex polyps. As such, this technique may be useful in the West, in centers, where previous gastric ESD is not frequent or Japanese mentoring is not possible.

Genetic impact of methylenetetrahydrofolate reductase (MTHFR) polymorphism on the susceptibility to colorectal polyps: a meta-analysis

Background

There are several studies with inconsistent conclusions regarding the association between the rs1801133 and rs1801131 polymorphisms within the MTHFR (methylenetetrahydrofolate reductase) gene and colorectal polyp risk. This discrepancy led us to assess the genetic impact of the two polymorphisms on the susceptibility to colorectal polyps.

Methods

A meta-analysis was carried out for quantitative synthesis. According to the inclusion/exclusion criteria, we retrieved, screened and selected all published articles related to colorectal polyps and the MTHFR rs1801133 and rs1801131 polymorphisms. The P value of association test, RRs (risk ratios) and 95% CIs (confidence intervals) were mainly produced.

Results

A total of twenty-three case-control studies were included from twenty-two eligible articles. Pooling the results of both rs1801133 and rs1801131 polymorphisms in the overall population suggested a nonsignificant association between colorectal polyp cases and controls, in that all P values in the test of association were larger than 0.05. Nevertheless, pooling results in the “UK” subgroup of rs1801131, comprising five studies (1257 cases/1407 controls), indicated an elevated risk in colorectal polyp cases in comparison with controls, under the genetic models of CC vs. AA (P = 0.032, RR = 1.27, 95% CIs = 1.02, 1.57) and CC vs. AA+AC (P = 0.036, RR = 1.27, 95% CIs = 1.02, 1.60).

Conclusion

The C/C genotype of MTHFR rs1801131 is more likely to be a genetic risk factor for colorectal polyps in the UK region, although this finding should be verified with a larger sample size.

Electronic supplementary material

The online version of this article (10.1186/s12881-019-0822-y) contains supplementary material, which is available to authorized users.

Colorectal carcinogenesis: Insights into the cell death and signal transduction pathways: A review

Colorectal carcinogenesis (CRC) imposes a major health burden in developing countries. It is the third major cause of cancer deaths. Despite several treatment strategies, novel drugs are warranted to reduce the severity of this disease. Adenomatous polyps in the colon are the major culprits in CRC and found in 45% of cancers, especially in patients 60 years of age. Inflammatory polyps are currently gaining attention in CRC, and a growing body of evidence denotes the role of inflammation in CRC. Several experimental models are being employed to investigate CRC in animals, which include the APC^min/+ mouse model, Azoxymethane, Dimethyl hydrazine, and a combination of Dextran sodium sulphate and dimethyl hydrazine. During CRC progression, several signal transduction pathways are activated. Among the major signal transduction pathways are p53, Transforming growth factor beta, Wnt/β-catenin, Delta Notch, Hippo signalling, nuclear factor erythroid 2-related factor 2 and Kelch-like ECH-associated protein 1 pathways. These signalling pathways collaborate with cell death mechanisms, which include apoptosis, necroptosis and autophagy, to determine cell fate. Extensive research has been carried out in our laboratory to investigate these signal transduction and cell death mechanistic pathways in CRC. This review summarizes CRC pathogenesis and the related cell death and signal transduction pathways.