Complex Polyps Research Articles

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

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

The impact of a multidisciplinary team approach on the management of patients diagnosed with complex colorectal polyps.

Large nonpedunculated colorectal polyps (LNPCPs) have a greater than average risk of malignancy, incomplete resection/recurrence and complications associated with treatment. Appropriate management of these lesions is crucial to prevent cancer and reduce harm. The British Society of Gastroenterologists (BSG) and the Association of Coloproctologists of Great Britain and Ireland (ACPGBI) published guidelines for the management of LNPCPs in 2015. The aim of this work was to evaluate the case mix and outcomes from a single centre's multidisciplinary approach to managing such lesions against the key performance indicators (KPIs) set within these national guidelines. Cohort study from a single centre over a 2-year period, January 2020 to December 2022. After exclusions, a total of 229 cases were discussed. Most complex polyps were treated endoscopically, with conservative management recommended in 22 cases where patients had significant comorbidities and were unlikely to benefit from therapy. The overall surgical intervention rate (including transanal endoscopic microsurgery/per anal excision) was 14%. Of the cases treated endoscopically, there was residual polyp detected in 3.9% at 12-months' follow-up. Complications were rare. There was a single case of perforation following endoscopic submucosal dissection and no significant postprocedure bleeds. There were no perforations following endoscopic mucosal resection, although postpolypectomy bleeding requiring admission occurred in 4%. Sixty-eight per cent of patients were treated within 56 days of multidisciplinary team (MDT) discussion, despite the timeframe being within a period of huge disruption due to the global COVID pandemic. KPI standards published by the BSG were therefore met. MDT management of complex polyps (LNPCPs) is effective and meets the standards set by national guidance. Patient outcomes following treatment for complex polypectomy are improved when the most appropriate procedure is performed by the most appropriate operator. Discussion at a complex polyp MDT can facilitate this approach.

Transcecal endoscopic appendectomy for management of complex appendiceal polyps extending into the appendiceal orifice.

Background and study aims Endoscopic resection of appendiceal orifice (AO) polyps extending inside the appendiceal lumen is challenging given the inability to determine polyp lateral margins and risk of appendicitis. Transcecal endoscopic appendectomy (TEA) ensures en bloc resection of these complex polyps. Patients and methods This case series includes patients who underwent TEA by a single endoscopist in the United States. Technical success was defined as achieving complete removal of the appendix along with AO polyp in an en bloc fashion. Results In total, nine patients were included (mean age 69.7 ± 9.6 years). The average appendix size was 4.07 ± 2.02 cm. Technical success was achieved in 100% of the patients. The average procedure length was 118.1 ± 44.21 minutes. The en bloc resection rate, R0 resection rate, and curative resection rates were 100%. Patients were observed for an average of 3.1 ± 1.6 days. One patient developed loculated fluid collection 9 days post procedure, which resolved on its own with oral antibiotic therapy. No other adverse events were recorded. Conclusions This was an early study of the feasibility of TEA in the United States. This novel technique, in early-stage development, is potentially safe and associated with a minimal risk profile in expert hands. Further prospective studies are needed to standardize the technique.

Current Trends in the Management of a Complex Polyp: Endoscopy versus Surgery

AbstractMany colorectal cancers arise from either adenomatous polyps or sessile serrated lesions. However, due to the implementation of screening guidelines at the age of 45 years and the ability to perform therapeutic endoscopic polyp resections, the incidence and mortality of colorectal cancer has been decreasing in the United States. Polyps can be distinguished not only by pathology, but characterized by their complexity depending on the size, location, and morphology. Historically, polyps that were endoscopically more challenging to resect were referred for surgical resection. However, due to rapid advancement in endoscopic techniques and availability of tools, many of these complex polyps can be safely and effectively resected endoscopically. In this section, we review the different methods and potential challenges associated with endoscopic resection techniques including endoscopic mucosal resection, endoscopic submucosal dissection, or endoscopic full-thickness resection of a complex polyp.

Combined Endo-Laparoscopic Surgery (CELS) for the management of complex colorectal lesions

Detection of colon polyps is common and is expected in 20–30 % of screening colonoscopies. As the number of colonoscopies performed increases, the detection of advanced and difficult to resect polyps will also rise. These polyps tend to be larger, greater than 2 cm, have flat morphology, and are in difficult anatomic locations behind haustral folds or at sharp flexures of the colon. Advanced endoscopic techniques such as endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are useful to remove these polyps. However, many polyps remain unresectable with these techniques. Combined endoscopic laparoscopic surgery (CELS) has shown to be an effective technique to facilitate safe removal of complex polyps. CELS encompasses a variety of techniques including laparoscopic assisted ESD/EMR and laparo-endoscopic full thickness excisions (FLEX). Success rate of CELS ranges from 70 to 100 %, with less than 5 % conversion to colectomy. Perioperative outcomes boast shorter hospital length of stay, with low rates of serious post-op complications when compared to colectomy. Malignancy rate after CELS in appropriately selected patients is low, ranging from 1.6 %-10 % of cases. Polyp recurrence rate after CELS is also low, usually less than 10 %. Use of CELS for early-stage cancers remains controversial but maybe adequate in appropriately selected patients. Further evaluation and long-term studies are needed to study its efficacy in cases of known cancer. The purpose of this review is to provide recommendations for use of CELS techniques, appropriate indications, describe technical tips, and review potential future applications.

The effect of implementing a transanal minimally invasive surgical programme for the local excision of early rectal neoplasia on outcomes in a tertiary referral rectal cancer centre.

Transanal minimally invasive surgery (TAMIS) is a surgical alternative to proctectomy in the management of complex rectal polyps and early rectal cancers. In 2016, our institution introduced a TAMIS programme. The purpose of this study was to evaluate changes in practice and outcomes in our institution in the 3 years before and after the implementation of TAMIS. We conducted a retrospective analysis of a prospective database of patients who underwent proctectomy or TAMIS for the management of complex rectal polyps or early rectal cancers at our institution between 2013 and 2018. 96 patients were included in this study (41 proctectomy vs 55 TAMIS). A significant reduction was noted in the number of proctectomies performed in the 3 years after the implementation of TAMIS as compared to the 3 years before (13 vs 28) ( P < 0.001); 43% of patients ( n = 12) who underwent proctectomy in the period prior to implementation of TAMIS were American Society of Anaesthesiologists grade III, as compared to only 15% ( n = 2) of patients during the period following TAMIS implementation ( P = 0.02). TAMIS was associated with a significant reduction in length of inpatient stay ( P < 0.001). Oncological outcomes were comparable between groups (log rank P = 0.83). Our findings support TAMIS as a safe and effective alternative to radical resection. The availability of TAMIS has resulted in a significant reduction in the number of comorbid patients undergoing proctectomy at our institution. Consequently, we have observed a significant reduction in postoperative complications over this time period.

A123 THE EFFECTS OF INFLAMMATORY BOWEL DISEASE ON THE MANAGEMENT AND OUTCOMES OF COMPLEX POLYPS IN PATIENTS UNDERGOING SURVEILLANCE COLONOSCOPY: A RETROSPECTIVE COHORT STUDY

Abstract Background The influence of inflammatory bowel disease (IBD) on the outcomes of complex polyps remains an area of uncertainty. Aims To investigate the impact of IBD on the management and outcomes of complex polyps during surveillance colonoscopy. Methods This retrospective cohort study utilized a prospectively collected database, involving patients who underwent surveillance colonoscopy for colorectal cancer or IBD surveillance who were identified to have complex polyps between February 2019 and December 2020 in Southwestern Ontario. Patient demographics, disease characteristics, medication history, polyp description and management were analyzed. The data were summarized in median and interquartile range for continuous variable and frequency and percentage for categorical variables. Characteristics between IBD and non-IBD were compared using the Wilcoxon rank sum test and Fisher’s exact test, as appropriate. Results 383 patients were included in the study, of which 27 individuals had IBD (5 Crohn's disease, 13 ulcerative colitis, and 9 indeterminate colitis). Patients with IBD were generally younger than their non-IBD counterparts (median age 61 vs 67 respectively). No significant differences were identified in terms of rates of complete polyp removal (17.70 % vs 22.22 %, pampersand:003C0.602), residual polyps after resection (76.97% vs 70.37%, pampersand:003C0.476), repeat removal attempts (84.27% vs 74.07%, pampersand:003C0.179), or surgical intervention (88.76% vs 88.89%, pampersand:003C0.99). A higher proportion of IBD patients were managed by gastroenterologists vs other endoscopists (81.48% vs. 40.17%, p ampersand:003C 0.001). No significant differences in complex polyp characteristics were observed, except in difficult locations of complex polyps were more common in the non-IBD cohort (55.34% vs 25.93%, pampersand:003C0.004). Conclusions In this retrospective cohort study, IBD does not appear to influence the management or outcome of complex polyps. Larger studies are required given the small IBD cohort size in this study. Funding Agencies None

Hybrid endoscopic approaches for complex colorectal polyps with a non-lifting sign: the Greek experience.

Hybrid approaches combining endoscopic full-thickness resection (EFTR) with conventional techniques (endoscopic mucosal resection [EMR], endoscopic submucosal dissection [ESD]) have enabled the resection of difficult fibrotic colorectal adenomas exhibiting a "non-lifting" sign, and polyps in difficult positions. We present our cohort treated with either EMR+EFTR or ESD+EFTR as salvage hybrid endoscopic approaches for complex colorectal polyps not amenable to conventional techniques. Retrospective analysis included technical success, histological confirmation of margin-free resection, assessment of adverse events and follow up with histological assessment. All patients underwent follow-up endoscopy at least 6 and 12 months post-resection. Fourteen patients underwent hybrid EFTR procedures (11 EMR+EFTR and 3 ESD+EFTR). Technical success was achieved in all cases where the full-thickness resection device (FTRD) was advanced to the site of the resection (100%). In 2 cases, the FTRD system could not be passed through the sigmoid colon because of severe chronic diverticulitis, subsequent fibrosis and stiffness. The mean lesion size in the EMR+EFTR group (41.7 mm; range 20-50 mm) was larger than the ESD+EFTR group (31.7 mm; range 30-35 mm). Six patients (42.9%) were histologically diagnosed with T1 carcinoma. The mean duration of hospitalization was 1.4 days. Follow-up endoscopy was available in all patients and no recurrence was observed with histological confirmation during a mean follow-up period of 15.4 months. Hybrid procedures appear to be safe and effective treatments for complex colorectal lesions not amenable to EMR, ESD or EFTR alone, because of the lesion size, positive non-lifting sign, and difficult positions.

S179 Enhancing Colonoscopy Outcomes: A Systematic Review of the Clinical Effectiveness of a Novel Rigidizing Overtube in Completing Difficult Colonoscopies and Achieving Complex Polyp Resection

S179 Enhancing Colonoscopy Outcomes: A Systematic Review of the Clinical Effectiveness of a Novel Rigidizing Overtube in Completing Difficult Colonoscopies and Achieving Complex Polyp Resection

Colorectal polyp classification and management of complex polyps for surgeon endoscopists.

SummaryIncreasing familiarity with advanced endoscopic excision techniques allows for more colorectal lesions to be removed without major surgery. Endoscopic excision with negative margins is adequate for most polyps and low-risk T1 cancers. The use of modern polyp classification techniques based on size, morphology and pit pattern by an experienced endoscopist allow for an optical diagnosis of these lesions and can predict, with high accuracy, which lesions contain malignant disease and the level of invasion. A surgeon endoscopist must be able to recognize which complex polyps can be resected with advanced polypectomy techniques and which require upfront surgery. We aimed to provide an overview of polyp classification techniques to help surgeons select the correct treatment algorithm for advanced colorectal lesions based on their visual characteristics at index endoscopy.

Benchmarking Polyp Segmentation Methods in Narrow-Band Imaging Colonoscopy Images.

In recent years, there has been significant progress in polyp segmentation in white-light imaging (WLI) colonoscopy images, particularly with methods based on deep learning (DL). However, little attention has been paid to the reliability of these methods in narrow-band imaging (NBI) data. NBI improves visibility of blood vessels and helps physicians observe complex polyps more easily than WLI, but NBI images often include polyps with small/flat appearances, background interference, and camouflage properties, making polyp segmentation a challenging task. This paper proposes a new polyp segmentation dataset (PS-NBI2K) consisting of 2,000 NBI colonoscopy images with pixel-wise annotations, and presents benchmarking results and analyses for 24 recently reported DL-based polyp segmentation methods on PS-NBI2K. The results show that existing methods struggle to locate polyps with smaller sizes and stronger interference, and that extracting both local and global features improves performance. There is also a trade-off between effectiveness and efficiency, and most methods cannot achieve the best results in both areas simultaneously. This work highlights potential directions for designing DL-based polyp segmentation methods in NBI colonoscopy images, and the release of PS-NBI2K aims to drive further development in this field.

Use of anchor pronged clips to close complex polyp resection defects.

Video 1Demonstration of anchored pronged clips to close complex polyp resection defects.

Commentary.

Endoscopic full-thickness resection (EFTR) is increasingly used for local resection of suspected T1 colorectal carcinoma (CRC), completing scar excision after an R1/Rx resection of pT1 CRC, and for nonlifting residual or recurrent adenoma. The technique has some important advantages such as an en bloc resection for optimal histological evaluation, the high chance of obtaining an R0 resection especially at the vertical margin, and the technical ability to remove complex polyps by endoscopy, where more conventional techniques would likely fail. Recent publications including large cohorts have shown that the EFTR technique is both safe and effective in a large number of selected and deemed suitable cases.

Planning management for complex colorectal polyps: a qualitative assessment of factors influencing decision-making among colonoscopists

ObjectiveEndoscopic therapy is the recommended primary treatment for most complex colorectal polyps, but high colonic resection rates are reported. The aim of this qualitative study was to understand and compare...

A131 ENDOSCOPIC SUBMUCOSAL DISSECTION OF COLORECTAL ADENOMAS AND EARLY ADENOCARCINOMAS: OUTCOMES FROM BRITISH COLUMBIA

Abstract Background Endoscopic resection is the standard of care for the management of colorectal polyps. Larger and more complex polyps require endoscopic mucosal resection (EMR). While complications have been low, EMR is often piecemeal, resulting in indeterminant margins and often a higher recurrence rate. Endoscopic submucosal dissection (ESD) is an advanced endoscopic resection technique with a higher rate of en bloc resection. While more data exist for the resection of gastric lesions with ESD, ESD is becoming more widely used in western countries for the resection of colorectal lesions. Purpose The purpose of this study is to report on the outcomes and rates of complications for colorectal ESD completed in a tertiary centre in British Columbia. Method All colorectal ESD was completed by a senior therapeutic endoscopist who has previously received training in Japan. Retrospective data were collected on all colorectal ESD procedures done in St. Paul’s Hospital from July 11th, 2016, when the procedure first became available, to Aug 30th, 2022. Inclusion criteria were all adults who have undergone ESD for resection of a colorectal lesion. Exclusion criteria were patients younger than 18. Data collected included demographic variables, polyp characteristics, procedural outcomes, and complications. Result(s) A total of 39 ESD procedures were completed. The mean size of the resected lesion was 30.4 mm (range: 5 – 60 mm). Technical success, defined as successful resection of all polypoid tissue, was achieved in 35/39 procedures (89.7%). En-bloc resection was achieved in 27/35 (77.1%) of the completed ESD. The rate of R0 resection was 22/35 (62.9%). Curative resection, defined as technically successful ESD with R0 margin and no lymphovascular invasion, was achieved in 23/39 (59.0%) of the cases and the majority of the patients with non-curative resection that underwent endoscopic surveillance had no recurrence on follow-up. In our cohort, 3/39 (7.7%) patients had adenocarcinoma. None of the ESD resulted in any intra-procedural or delayed perforation. 3/39 (7.7%) patients had clinically significant post-endoscopic resection bleeding. Out of 24 patients that completed follow-up, 4 (16.7%) had recurrence at the resection site that was managed endoscopically. 4/39 (10.3%) of patients required surgery post-ESD. Conclusion(s) In our cohort, ESD is an effective endoscopic resection modality for the management of colorectal adenomas and early adenocarcinoma with a high rate of technical success and low rates of complications. Although the rate of curative resection was low, most were the result of R1 or Rx resection and a majority of the follow-ups in this subgroup demonstrated no further recurrence. The rate of en bloc resection is high, especially given the average size of adenomas in this cohort. Although ESD requires high technical proficiency, its favorable outcomes and low complication rates make ESD highly feasible for the resection of colorectal lesions. Please acknowledge all funding agencies by checking the applicable boxes below None Disclosure of Interest None Declared

Outcomes of complex colorectal polyps managed by multi-disciplinary team strategies—a multi-centre observational study

PurposeTeam management strategies for complex colorectal polyps are recommended by professional guidelines. Multi-disciplinary meetings are used across the UK with limited information regarding their impact. The aim of this multi-centre observational study was to assess procedures and outcomes of patients managed using these approaches.MethodThis was a retrospective, observational study of patients managed by six UK sites. Information was collected regarding procedures and outcomes including length of stay, adverse events, readmissions and cancers.ResultsTwo thousand one hundred ninety-two complex polyps in 2109 patients were analysed with increasing referrals annually. Most presented symptomatically and the mean polyp size was 32.1 mm. Primary interventions included endoscopic therapy (75.6%), conservative management (8.3%), colonic resection (8.1%), trans-anal surgery (6.8%) or combined procedures (1.1%). The number of primary colonic resections decreased over the study period without a reciprocal increase in secondary procedures or recurrence. Secondary procedures were required in 7.8%. The median length of stay for endoscopic procedures was 0 days with 77.5% completed as day cases. Median length of stay was 5 days for colonic resections. Overall adverse event and 30-day readmission rates were 9.0% and 3.3% respectively. Malignancy was identified in 8.8%. Benign polyp recurrence occurred in 13.1% with a median follow up of 30.4 months. Screening detected lesions were more likely to undergo bowel resection. Colonic resection was associated with longer stays, higher adverse events and more cancers on final histology.ConclusionMulti-disciplinary team management of complex polyps is safe and effective. Standardisation of organisation and quality monitoring is needed to continue positive effects on outcomes and services.

Distal Cap-assisted Endoscopic Mucosal Resection for Non-lifting Colorectal Polyps: An International, Multicenter Study

Background and AimsSubmucosal fibrosis is a commonly encountered problem associated with complex polyps referred for endoscopic mucosal resection (EMR). Previous biopsies, submucosal tattoo injection, and previous unsuccessful attempts at polyp resection have all been shown to induce submucosal fibrosis, which makes subsequent EMR more difficult and increases the risk of recurrence. MethodsWe conducted a multicenter, international, retrospective study of 61 distal cap-assisted endoscopic mucosal resection (EMR-DC) cases done for the indication of a non-lifting colorectal lesion occurring after a previous biopsy, tattoo, or attempted resection at 3 tertiary referral centers. ResultsEMR-DC was preceded by attempted polypectomy or EMR in 88.5% of cases, submucosal tattoo injection in 2%, previous biopsy in 5%, and both biopsy and tattoo in 5%. Complete macroscopic resection was achieved in 100% of EMR-DC procedures in an average procedure time of 49.5 minutes. The adenoma recurrence rate for these adherent lesions at surveillance (average 6.6 months) was only 9.8%. Two serious adverse events occurred (3.3%) within 30 days of the procedure: one instance of postprocedural bleeding and one episode of post-polypectomy syndrome. ConclusionThis large, multicenter series demonstrates EMR-DC to be a safe, effective, and efficient approach to a difficult and common clinical problem: adherent and non-lifting polyps. It may offer several advantages over more expensive or invasive endoscopic techniques used for this indication. The use of EMR-DC for larger adherent polyps with adjuvant techniques such as hot avulsion or cold forceps avulsion with adjuvant snare tip soft coagulation for smaller adherent sections may represent an ideal approach.

Bulking agents in gastrointestinal endoscopy: present applications and future advances.

Bulking agents are inert materials injected into an organ to affect the physical properties of the organ for a therapeutic purpose. Various agents have been developed to aid in the treatment of diseases like gastroesophageal reflux disease (GERD), fecal incontinence, obesity, malignancy, hemostasis, and tissue dissection. Here, we review the state of the art in bulking agents in gastrointestinal endoscopy, past failures, current limitations, and where we see the field heading in the future. Though bulking agents have been trialed for various different gastrointestinal diseases, there are currently limited uses in gastrointestinal endoscopy. Though various agents have been trialed for GERD, numerous complications and adverse events have limited its current use. However, for the treatment of fecal incontinence endoscopic bulking agent therapy is a reasonable option. Though in early stages of exploration, bulking agent therapy for enteric protection from radiotherapy may be a promising tool to improve treatment of pancreatic cancer. Bulking agents for tissue dissection have substantially improved lifting agents and complex polyp removal. Bulking agent therapy has not really been explored for endoscopic bariatric therapy or hemostasis but may be a fruitful area for exploration in the future. Bulking agent therapy has been trialed for various gastrointestinal diseases with mixed success. There is currently a therapeutic roll in the endoscopic management of fecal incontinence and tissue dissection. A future role in the treatment of GERD, obesity, malignancy, and hemostasis seem feasible.

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

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. This study aimed to understand experiences of having a complex polyp removed and how this may influence quality of life. Semi-structured telephone interviews were conducted, and a thematic approach was used for data analysis. All participants had a complex polyp removed after a positive stool test and review by Bowel Screening Wales' Network Multi-Disciplinary Team. 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. Experiences of complex polyp removal were generally positive, with minimal changes in quality of life. 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. Four patient and public involvement partners provided feedback on participant materials.

Intra- and Interobserver Variability of Shear Wave Elastography in Rectal Cancer.

Simple SummaryFor a diagnostic tool to be important, there must be a high level of agreement between different observers. If not, the reliability of the measurement can not be considered valid. Previous studies have evaluated the reproducibility of tissue stiffness measurements of rectal tumors, but only on previously obtained images. Therefore, we aimed to investigate the issue in a clinical setting and found a high level of agreement between observers.Background: Endorectal ultrasound (ERUS) is an important tool when evaluating complex rectal adenomas and rectal cancer, and the accuracy is improved by adding elastography measurements. A high interobserver agreement is imperative in clinical practice. Therefore, the aim of this study was to evaluate interobserver agreement assessed on real-time images. Additionally, we investigated the intra- and interobserver agreement between experienced and inexperienced observers. Materials and methods: We prospectively included patients referred to an ERUS at the Department of Radiology with a complex rectal polyp or suspected rectal malignancy. Two operators independently scanned each patient in turn. Furthermore, four observers assessed previously obtained images using three different methods for placing the region of interest (ROI). Three months later, the four observers reassessed the images to assess intraobserver variability. Results: A total of 19 patients were included for live assessment. Agreement of tumor classification was substantial for T stage (kappa: 0.86) and fair for N stage (kappa: 0.73), with an absolute agreement for T and N stages of 84% and 89%, respectively. Agreement of SWE was good for Emean (ICC 0.94, 95% CI 0.86–0.98) and fair for Emax (ICC 0.85, 95% CI 0.66–0.94). Intra- and interobserver agreement between inexperienced and experienced observers showed good to excellent agreement with all ROI methods. Conclusion: Interobserver agreement is high in SWE when performed in a clinical setting. We found the best agreement using the mean value of several ROIs. Intra- and interobserver agreement was high regardless of operator experience.