Current standards and new developments of colorectal polyp management and resection techniques

A Comparison of Incomplete Resection Rate of Large and Small Colorectal Polyps by Cold Snare Polypectomy

BACKGROUND & AIMS

There are limited data regarding the safety and efficacy of cold snare polypectomy (CSP) for large colorectal polyps. We evaluated factors affecting the clinical outcomes of CSP for polyps between 5 and 15 mm in size.

METHODS

This was a prospective single-center observational study involving 1000 patients undergoing colonoscopy. Polyps (5-15 mm) were removed using CSP, and biopsies were taken from the resection margin. The primary outcome was the incomplete resection rate (IRR), and was determined by the presence of residual neoplasia on biopsy. Correlations between IRR and polyp size, morphology, histology, and resection time were assessed by generalized estimating equation model.

RESULTS

A total of 440 neoplastic polyps were removed from 261 patients. The overall IRR was 2.27%, 1.98% for small (5-9 mm) vs 3.45% for large (10-15 mm) polyps (P = .411). In univariate analysis, the IRR was more likely to be related to sessile serrated lesions (odds ratio [OR], 6.93; 95% confidence interval [CI], 1.88-25.45; P = .004), piecemeal resection (OR, 11.83; 95% CI, 1.20-116.49; P = .034), and prolonged resection time >60 seconds (OR, 7.56; 95% CI, 1.75-32.69; P = .007). In multivariable regression analysis, sessile serrated lesions (OR, 6.45; 95% CI, 1.48-28.03; P = .013) and resection time (OR, 7.39; 95% CI, 1.48-36.96; P = .015, respectively) were independent risk factors for IRR. Immediate bleeding was more frequent with resection of large polyps (6.90% vs 1.42%; P = .003). No recurrence was seen on follow-up colonoscopy in 37 cases with large polyps.

CONCLUSIONS

CSP is safe and effective for removal of colorectal polyps up to 15 mm in size, with a low IRR. (ClinicalTrials.gov; Number: NCT03647176).

Clinical value of daytime colonoscopic polypectomy

BACKGROUND

In recent years, with the continuous development of endoscopic technology, colonoscopic polyposectomy has become the preferred method for the treatment of colorectal polyps. Its advantages of being minimally invasive, fast, safe, and cost-effective have been widely recognized in clinical practice. How to provide high quality medical services while effectively reducing medical costs, shorten the length of stay, and save medical resources is an urgent problem to be solved in the medical field.

AIM

To analyze the feasibility of the daytime surgery mode of painless colonoscopy polypectomy and to study its clinical value.

METHODS

A total of 2251 patients who underwent painless colonoscopy polypectomy at our hospital from March 2019 to May 2021 were selected. According to the patients' willing, 879 patients were divided into a daytime surgery group (observation group) and 1372 patients were divided into a routine inpatient non-daytime surgery group (control group). The clinical efficacy and prognosis of the two groups were compared and analyzed.

RESULTS

All patients in the two groups successfully completed colonoscopic polypectomy, and there were no readmission or death cases. There were no significant differences between the two groups in age, gender, number of polyps, operation time, postoperative complications, or number of readmissions within 30 d (P > 0.05). The average length of hospital stay in the observation group was (20.5 ± 3.2) h, and the total treatment cost (including outpatient examination cost) was (2968.8 ± 677.2) yuan, both of which were significantly lower than those of the general hospitalized surgery patients in the same period. The satisfaction of the observation group was significantly higher than that of the control group (t = 9.45, P < 0.05). No abdominal infection, anesthesia accident, gastrointestinal bleeding, perforation, or other serious complications occurred in the two groups, and the pathological results after surgery showed that all patients had a benign disease. Both groups were followed for 30 d, and no one was readmitted due to postoperative complications.

CONCLUSION

Compared with common inpatient surgery, daytime colonoscopic polypectomy can significantly shorten the length of hospital stay and reduce the cost of hospitalization. On the premise of reasonable optimization of treatment path, choosing suitable patients with appropriate indications for daytime surgery is not only safe and feasible, but also has the advantages of reducing medical costs and effectively utilizing medical resources.

Application of deep learning based artificial intelligence technology in identification of colorectal polyps

Colorectal cancer is a cancer type that is most suitable for screening since subjects at risk of this malignancy can clearly benefit from colonoscopy screening. In 2017, there were about 431951 new cases of colorectal cancer in China, with an increase of 203.5% in 28 years. Early detection and early removal of adenomatous polyps and other precancerous lesions during colonoscopy can prevent the occurrence of colorectal cancer. However, various factors lead to missed diagnosis of polyps during colonoscopy, which increases the risk of colorectal cancer. In recent years, with the rapid development of artificial intelligence technology in the medical field, colonoscopy assisted by artificial intelligence can increase the detection rate of polyps and improve the quality of colonoscopy. This paper mainly reviews the quality control, bowel preparation, diagnosis and classification of colorectal polyps, and the future opportunities and challenges faced by convolutional neural network based artificial intelligence technology in the field of colonoscopy, hoping to provide some reference for clinical work.

Analysis of 234 cases of colorectal polyps treated by endoscopic mucosal resection

BACKGROUND

Colorectal polyps refer to all neoplasms that protrude into the intestinal cavity. Researchers believe that 50%-70% of colorectal cancers originate from adenomatous polyps.

AIM

To investigate the endoscopic morphologic features, pathologic types, and clinical situation; evaluate the efficacy and safety of endoscopic mucosal resection (EMR); and guide clinicians in their daily practice.

METHODS

Two hundred thirty-four patients who underwent EMR in our hospital from January 1, 2018 to December 31, 2019 were recruited. Data including sex, age, endoscopic morphology of the polyps, and pathological characteristics were analyzed among groups.

RESULTS

A total of 295 polyps were resected from the 234 subjects enrolled in the study, of which 4 (1.36%) were Yamada type I. There were 75 (25.42%) type II, 101 (34.24%) type III, and 115 (38.98%) type IV adenomas. Among them, 41 were non-adenomas, 110 were low-risk adenomas, 139 were high-risk adenomas, and 5 were carcinomas. The differences in distribution were not statistically significant, with P values greater than 0.05. The risk of cancer significantly increased for polyps ≥ 1 cm in diameter (c² = 199.825, P = 0.00). Regarding the endoscopic morphological features, congestion, erosion, and lobulation were more common on the surface morphology of high-risk adenomas and cancerous polyps (c² = 75.257, P = 0.00), and most of them were Yamada types III and IV. In all, 6 of the 295 polyps could not be removed completely, with a one-time resection rate of 97.97%. There were two cases of postoperative bleeding and no cases of perforation, with an overall complication rate of 0.09%.

CONCLUSION

Colorectal polyps ranging from non-adenomatous polyps, low-risk adenomas, and high-risk adenomas to adenocarcinomas each has their own endoscopic features, while EMR, as a mature intervention, has good safety and operability and should be promoted clinically, especially at the primary care level.

The risk factors for delayed bleeding after endoscopic resection of colorectal tumors: a meta-analysis

INTRODUCTION

The most common complication of post-colorectal endoscopic resection is delayed bleeding. The assessment of risk factors for delayed bleeding provides important and useful information in standard clinical operations. The risk factors have been previously reported; however, they remain inconsistent across different studies.

AREAS COVERED

In this meta-analysis, the patient conditions, lesion-related factors, and operation-related factors were compared between delayed bleeding and no bleeding. PubMed, Cochrane, Embase, China National Knowledge Infrastructure (CNKI), and Wanfang Database were searched to identify eligible studies. Pooled odds ratio (OR) and 95% confidence intervals (CI) were calculated along with heterogeneity.

EXPERT OPINION

This study is the first meta-analysis to investigate risk factors for colorectal delayed bleeding. We found several risk factors contributing to this condition: colorectal tumors located in the proximal colon, a history of antithrombotic drug use, high-grade intraepithelial neoplasia or early cancer, piecemeal resection, intraoperative hemorrhage, no clip placement, and severe submucosal fibrosis. Despite our findings, we also conclude that more high-quality, large-scale clinical randomized controlled studies are needed due to limited retrospective studies at present. Future therapeutic colonoscopies should focus on precise diagnosis, treatment safety, and management during the perioperative period.

The efficacy and safety of sulindac for colorectal polyps: A protocol for systematic review and meta-analysis

BACKGROUND

Sulindac has been used for treating colorectal polyps widely. However, the efficacy and safety of sulindac for colorectal polyps are unclear. This study aims to evaluate the efficacy and safety of sulindac for colorectal polyps.

METHODS

Randomized controlled trials of sulindac in the treatment of colorectal polyps will be searched in PubMed, EMbase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), WanFang, the Chongqing VIP Chinese Science, and Technology Periodical Database, and China biomedical literature database (CBM) from inception to August, 2020. And Baidu Scholar, Google Scholar, International Clinical Trials Registry Platform, and Chinese Clinical Trials Registry will be searched to obtain more relevant studies comprehensively. Two researchers will perform data extraction and risk of bias assessment independently. Statistical analysis will be conducted in RevMan 5.3.

RESULTS

This study will summarize the present evidence by exploring the efficacy and safety of sulindac in the treatment of colorectal polyps.

CONCLUSION

The findings of the study will provide helpful evidence for the efficacy and safety of sulindac in the treatment of colorectal polyps, facilitating clinical practice and further scientific studies.

ETHICS AND DISSEMINATION

The private information from individuals will not publish. This systematic review also will not involve endangering participant rights. Ethical approval is not required. The results may be published in a peer-reviewed journal or disseminated in relevant conferences.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/N5GDH.

An international polypectomy practice survey

Background and study aims: In recent years, cold snare polypectomy (CSP) has been recommended as the preferred approach for removal of small and diminutive colorectal polyps. We conducted an international survey among endoscopists to understand the uptake of CSP and changes in polypectomy practice during recent years.Patients and methods: Endoscopists were invited through gastroenterology, colorectal surgery and endoscopy societies to participate in an online survey. The primary outcome was to identify the predominant polypectomy approach used to remove 4‒10 mm colorectal polyps. Secondary outcomes included the uptake of CSP in the past 5 years, current polypectomy practice patterns for 1‒20 mm polyps, practice changes in recent years, and perceived benefits/concerns related to different polypectomy techniques.Results: The survey was distributed internationally by nine societies and completed by 808 endoscopists (response rate 3.7%). CSP was the predominant polypectomy technique for 4‒5 mm polyps (67.0%, 95% CI, 63.7-70.2%) and 6‒10 mm polyps (55.2%, 95% CI, 51.8-58.6%). For 1‒3 mm polyps, cold forceps remained the predominant technique (78.4%, 95% CI, 75.6-81.3%), whereas hot snare polypectomy (HSP) remained the predominant technique for 10‒20 mm polyps (92.5%, 95% CI, 90.7-94.3%). 87.5% (95% CI, 85.2-89.8%) of endoscopists reported an increase in CSP use during the past 5 years.Conclusions: This survey found a substantial increase in CSP use during recent years. CSP has become the predominant polypectomy approach for 4‒10 mm colorectal polyps, while HSP remained the predominant approach for larger (10‒20 mm) polyps. Clinical practice patterns are well aligned with recently issued guideline recommendations.

Optical diagnosis of diminutive polyps in the Dutch Bowel Cancer Screening Program: Are we ready to start?

Background and study aims  Implementation of optical diagnosis of diminutive polyps may potentially increase the efficacy and cost-effectiveness of colonoscopies. To adopt such strategy in clinical practice, the Preservation and Incorporation of Valuable endoscopic Innovations (PIVI) thresholds provide the basis to be met: ≥ 90 % negative predictive value (NPV) for diagnosis of adenomatous histology and ≥ 90 % agreement on surveillance intervals. We evaluated this within the Dutch Bowel Cancer Screening Program (BCSP). Patients and methods  Endoscopic and histological data were collected from participants of the national bowel cancer screening program with an unfavorable fecal immunochemical test referred for colonoscopy between February 2014 and August 2015 at four endoscopy centers. The "resect and discard" scenario was studied, resecting diminutive polyps without histological evaluation. Agreement between optical diagnosis and histological diagnosis was measured for surveillance intervals according to Dutch, European and American post-polypectomy surveillance guideline. Results  Fifteen certified endoscopists participated in this study and included 3028 diminutive polyps. In 2,330 patients both optical and histological diagnosis were available. Optical diagnosis of diminutive polyps showed NPV of 84 % (95 % CI 80-87) for adenomatous histology in the rectosigmoid. Applying the 'resect and discard' strategy resulted in 90.6 %, 91.2 %, 90.9 % agreement on surveillance intervals for the Dutch, European and American guideline respectively. Conclusion  Our data representing current clinical practice in the Dutch BCSP practice on optical diagnosis of diminutive polyps showed that accuracy of predicting histology remains challenging, and risk of incorrect optical diagnosis is still significant. Therefore, it is too early to safely implement these strategies.

Transanal endoscopic operation for rectal lesion: a rapid initial experience

BACKGROUND

In recent decades, transanal surgery for rectal lesions has become a valid alternative treatment for the treatment of small lesions of the rectum. Significant benefits in terms of morbidity and mortality are confirmed. There are multiple platforms for transanal surgery but the TEO system® is one of the best known.

METHODS

Between November 2017 and July 2019, 25 patients with rectal lesions suitable to transanal treatment came to our observation. In all reported cases, full-thickness rectum resections were performed. Demographic, histopathological, surgical morbidity/mortality and clinical outcome in all patients who underwent TEO were retrospectively evaluated from a prospectively collected database.

RESULTS

For a period of less than 2 years, 25 rectal lesions were excised by TEO. Sixteen lesions (64%) were low (<4 cm), 7 (28%) were mid-rectal (4-8 cm) and 2 (8%) were in the proximal rectum (>8 cm). Postoperative complications included: 3 (12%) bleedings, and 8 (32%) post-polipectomy syndrome.

CONCLUSIONS

Our initial experience suggests TEO is safe and feasible. Full-thickness resection guarantees adequate deep margins. Moreover, the limited number of cases requires the development of adequate reference centers.

Polyp fingerprint: automatic recognition of colorectal polyps' unique features

BACKGROUND

Content-based image retrieval (CBIR) is an application of machine learning used to retrieve images by similarity on the basis of features. Our objective was to develop a CBIR system that could identify images containing the same polyp ('polyp fingerprint').

METHODS

A machine learning technique called Bag of Words was used to describe each endoscopic image containing a polyp in a unique way. The system was tested with 243 white light images belonging to 99 different polyps (for each polyp there were at least two images representing it in two different temporal moments). Images were acquired in routine colonoscopies at Hospital Clínic using high-definition Olympus endoscopes. The method provided for each image the closest match within the dataset.

RESULTS

The system matched another image of the same polyp in 221/243 cases (91%). No differences were observed in the number of correct matches according to Paris classification (protruded: 90.7% vs. non-protruded: 91.3%) and size (< 10 mm: 91.6% vs. > 10 mm: 90%).

CONCLUSIONS

A CBIR system can match accurately two images containing the same polyp, which could be a helpful aid for polyp image recognition.