First report from the International Evaluation of Endoscopic classification Japan NBI Expert Team: International multicenter web trial

Cold snare polypectomy versus hot endoscopic mucosal resection for large nonpedunculated colorectal polyps: a systematic review and meta-analysis of randomized controlled trials

This meta-analysis of randomized controlled trials (RCTs) aimed to compare the risk of recurrence and adverse events (AEs) between cold snare polypectomy (CSP) and hot endoscopic mucosal resection (H-EMR) for large nonpedunculated colorectal polyps (LNPCPs).A systematic search of Medline, Embase, and Cochrane Library databases until August 2024 was performed for studies comparing recurrence, bleeding, and perforation rates between CSP and H-EMR for LNPCPs ≥15 mm. A random-effects meta-analysis, with heterogeneity measured with I2, was conducted to generate pooled risk ratios (RRs) with 95%CIs.Four RCTs comprising 1516 LNPCPs (766 CSP and 750 H-EMR) in 1442 patients were included in the quantitative analysis. CSP demonstrated a higher recurrence risk at first surveillance colonoscopy than H-EMR in the pooled analysis (22.6% vs. 10.8%; RR 1.98; 95%CI 1.22-3.21; P = 0.02; moderate certainty evidence), corresponding to a number needed to harm of 9. Regarding AEs, CSP demonstrated a 67% reduced risk of delayed bleeding (1.2% vs. 3.9%; RR 0.33; 95%CI 0.12-0.89; P = 0.03; high certainty evidence), corresponding to a number needed to treat of 37. Although CSP appeared to reduce the risk of intraprocedural bleeding (10.0% vs. 19.8%; RR 0.30, 95%CI 0-52 256, P = 0.42), the wide confidence interval from the random-effects model included 1. There were no intraprocedural or delayed perforations in the CSP group.CSP has nearly double the recurrence risk of H-EMR for LNPCPs; however, its superior safety profile may make it a preferable option for patients where procedural safety is prioritized over radicality, such as those with extensive co-morbidities.

Usefulness of Magnifying Endoscopy With Narrow-Band Imaging for Diagnosis of Ulcerative Colitis-Associated Neoplasia

BACKGROUND AND AIM

Qualitative diagnosis of ulcerative colitis-associated neoplasia (UCAN) is crucial for surveillance colonoscopy in patients with ulcerative colitis (UC). Although the utility of magnifying endoscopy with narrow-band imaging (ME-NBI) in sporadic neoplasia diagnosis has been reported, its efficacy in UCAN remains unclear. This study aimed to evaluate the usefulness of ME-NBI for qualitative diagnosis of UCAN.

METHODS

We generated 60 ME-NBI images (30 UCANs and 30 nonneoplasia lesions, including 10 polypoid and 20 nonpolypoid lesions) from patients with UC who underwent colonoscopy at our hospital between 2015 and 2023. Eleven endoscopists (seven experts and four trainees) independently assessed these images. Lesions were categorized into high- (≥ 80%), moderate- (50%-79%), and low- (< 50%) accuracy groups on the basis of the correct diagnostic rate.

RESULTS

Overall sensitivity, specificity, and correct diagnostic rates were 66.5%, 79.0%, and 71.8%, respectively. Experts tended to exhibit higher specificity than trainees (83% vs. 70%). Polypoid lesions showed higher sensitivity (92% vs. 54%) and lower specificity (61% vs. 88%) than nonpolypoid lesions. Overall, the kappa value was 0.411. In UCAN, 37%, 37%, and 24% were classified into the high-, moderate-, and low-accuracy groups, respectively. All endoscopists assessed one case of UCAN in the low-accuracy group as a nonneoplastic vessel with a surface pattern. Only two nonneoplasias were identified as having nonneoplastic vessel and surface patterns by all endoscopists.

CONCLUSIONS

This study demonstrated the usefulness of ME-NBI for qualitative diagnosis, along with its limitations. A unique endoscopic diagnostic algorithm for UCAN, incorporating ME-NBI and other modalities, is necessary.

Endoscopic Resection for Colorectal Tumors

BACKGROUND

Endoscopic resection techniques for colorectal tumors are constantly evolving with improvements.

SUMMARY

Over the past decade, there has been a paradigm shift toward cold polypectomy for the removal of small lesions (<10 mm), known as the "cold revolution". In recent years, underwater endoscopic mucosal resection (EMR) has emerged as an alternative to conventional EMR and has been gaining popularity for resection of intermediate and large-sized lesions (≥10 mm). Although colorectal endoscopic submucosal dissection (ESD) requires a high level of advanced skills, improvements in dissection techniques and devices have facilitated the procedure. In Japan, the safety and efficacy of ESD for resecting large lesions (≥20 mm) have been demonstrated in a large-scale, multicenter, prospective cohort study (CREATE-J). ESD is also being increasingly adopted in Western countries. As endoscopic resection continues to advance and include large and more complex defects, a variety of closure techniques and new devices are being developed. Meanwhile, the number of endoscopic resections for T1-colorectal cancer (T1-CRC), including those intended for total excisional biopsy, has been increasing owing to the aging population and improvements in endoscopic technique.

KEY MESSAGES

This review provides a broad summary of endoscopic resection for colorectal tumors including advancements in closure techniques and devices for mucosal defects, as well as the potential role of endoscopic resection for patients with T1-CRC.

Diagnostic performance of the Japanese Narrow-band imaging expert team classification system using dual focus magnification in real-time Vietnamese setting

The JNET classification, combined with magnified narrowband imaging (NBI), is essential for predicting the histology of colorectal polyps and guiding personalized treatment strategies. Despite its recognized utility, the diagnostic efficacy of JNET classification using NBI with dual focus (DF) magnification requires exploration in the Vietnamese context. This study aimed to investigate the diagnostic performance of the JNET classification with the NBI-DF mode in predicting the histology of colorectal polyps in Vietnam. A cross-sectional study was conducted at the University Medical Center in Ho Chi Minh City, Vietnam. During real-time endoscopy, endoscopists evaluated the lesion characteristics and recorded optical diagnoses using the dual focus mode magnification according to the JNET classification. En bloc lesion resection (endoscopic or surgical) provided the final pathology, serving as the reference standard for optical diagnoses. A total of 739 patients with 1353 lesions were recruited between October 2021 and March 2023. The overall concordance with the JNET classification was 86.9%. Specificities and positive predictive values for JNET types were: type 1 (95.7%, 88.3%); type 2A (81.4%, 90%); type 2B (96.6%, 54.7%); and type 3 (99.9%, 93.3%). The sensitivity and negative predictive value for differentiating neoplastic from non-neoplastic lesions were 97.8% and 88.3%, respectively. However, the sensitivity for distinguishing malignant from benign neoplasia was lower at 64.1%, despite a specificity of 95.9%. Notably, the specificity and positive predictive value for identifying deep submucosal cancer were high at 99.8% and 93.3%. In Vietnam, applying the JNET classification with NBI-DF demonstrates significant value in predicting the histology of colorectal polyps. This classification guides treatment decisions and prevents unnecessary surgeries.

Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2024

1:  ESGE recommends cold snare polypectomy (CSP), to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of diminutive polyps (≤ 5 mm).Strong recommendation, high quality of evidence. 2:  ESGE recommends against the use of cold biopsy forceps excision because of its high rate of incomplete resection.Strong recommendation, moderate quality of evidence. 3:  ESGE recommends CSP, to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of small polyps (6-9 mm).Strong recommendation, high quality of evidence. 4:  ESGE recommends hot snare polypectomy for the removal of nonpedunculated adenomatous polyps of 10-19 mm in size.Strong recommendation, high quality of evidence. 5:  ESGE recommends conventional (diathermy-based) endoscopic mucosal resection (EMR) for large (≥ 20 mm) nonpedunculated adenomatous polyps (LNPCPs).Strong recommendation, high quality of evidence. 6:  ESGE suggests that underwater EMR can be considered an alternative to conventional hot EMR for the treatment of adenomatous LNPCPs.Weak recommendation, moderate quality of evidence. 7:  Endoscopic submucosal dissection (ESD) may also be suggested as an alternative for removal of LNPCPs of ≥ 20 mm in selected cases and in high-volume centers.Weak recommendation, low quality evidence. 8:  ESGE recommends that, after piecemeal EMR of LNPCPs by hot snare, the resection margins should be treated by thermal ablation using snare-tip soft coagulation to prevent adenoma recurrence.Strong recommendation, high quality of evidence. 9:  ESGE recommends (piecemeal) cold snare polypectomy or cold EMR for SSLs of all sizes without suspected dysplasia.Strong recommendation, moderate quality of evidence. 10:  ESGE recommends prophylactic endoscopic clip closure of the mucosal defect after EMR of LNPCPs in the right colon to reduce to reduce the risk of delayed bleeding.Strong recommendation, high quality of evidence. 11:  ESGE recommends that en bloc resection techniques, such as en bloc EMR, ESD, endoscopic intermuscular dissection, endoscopic full-thickness resection, or surgery should be the techniques of choice in cases with suspected superficial invasive carcinoma, which otherwise cannot be removed en bloc by standard polypectomy or EMR.Strong recommendation, moderate quality of evidence.