Impact of Annual Case Volume on Colorectal Endoscopic Submucosal Dissection Outcomes in a Large Prospective Cohort Study.

INTRODUCTION: The adoption of colorectal endoscopic submucosal dissection (ESD) is still limited in the West. A recent randomized trial showed that ESD is more effective and only slightly riskier than piecemeal endoscopic mucosal resection; reproducibility outside expert centers was questioned. We evaluated the results according to the annual case volume in a multicentric prospective cohort. METHODS: Between September 2019 and September 2022, colorectal ESD was consecutively performed at 13 participating centers classified as low volume (LV), middle volume (MV), and high volume (HV). The main procedural outcomes were assessed. Multivariate and propensity score matching analyses were performed. RESULTS: Three thousand seven hundred seventy ESDs were included. HV centers treated larger and more often colonic lesions than MV and LV centers. En bloc , R0, and curative resection rates were 95.2%, 87.4%, and 83.2%, respectively, and were higher at HV than at MV and LV centers. HV centers also achieved a faster dissection speed. Delayed bleeding and surgery for complications rates were 5.4% and 0.8%, respectively, without significant differences. The perforation rate (overall: 9%) was higher at MV than at LV and HV centers. Lesion characteristics, but not volume center, were independently associated with both R1 resection and perforation. However, after propensity score matching, R0 rates were significantly higher at HV than at LV centers, and perforation rates were significantly higher at MV than at HV centers. DISCUSSION: Colorectal ESD can be successfully implemented in the West, even in nonexpert centers. However, difficult lesions must still be referred to experts.

Computer-aided diagnosis improves characterization of Barrett's neoplasia by general endoscopists (with video).

BACKGROUND AND AIMS: Characterization of visible abnormalities in patients with Barrett's esophagus (BE) can be challenging, especially for inexperienced endoscopists. This results in suboptimal diagnostic accuracy and poor interobserver agreement. Computer-aided diagnosis (CADx) systems may assist endoscopists. We aimed to develop, validate, and benchmark a CADx system for BE neoplasia. METHODS: The CADx system received pretraining with ImageNet and then consecutive domain-specific pretraining with GastroNet, which includes 5 million endoscopic images. It was subsequently trained and internally validated using 1758 narrow-band imaging (NBI) images of early BE neoplasia (352 patients) and 1838 NBI images of nondysplastic BE (173 patients) from 8 international centers. CADx was tested prospectively on corresponding image and video test sets with 30 cases (20 patients) of BE neoplasia and 60 cases (31 patients) of nondysplastic BE. The test set was benchmarked by 44 general endoscopists in 2 phases (phase 1, no CADx assistance; phase 2, with CADx assistance). Ten international BE experts provided additional benchmark performance. RESULTS: Stand-alone sensitivity and specificity of the CADx system were 100% and 98% for images and 93% and 96% for videos, respectively. CADx outperformed general endoscopists without CADx assistance in terms of sensitivity (P = .04). Sensitivity and specificity of general endoscopists increased from 84% to 96% and 90% to 98% with CAD assistance (P < .001). CADx assistance increased endoscopists' confidence in characterization (P < .001). CADx performance was similar to that of the BE experts. CONCLUSIONS: CADx assistance significantly increased characterization performance of BE neoplasia by general endoscopists to the level of expert endoscopists. The use of this CADx system may thereby improve daily Barrett surveillance.

Safety and efficacy of salvage endoscopic submucosal dissection for Barrett's neoplasia recurrence after radiofrequency ablation.

BACKGROUND: This study evaluated the safety and efficacy of salvage endoscopic submucosal dissection (ESD) for Barrett's neoplasia recurrence after radiofrequency ablation (RFA). METHODS: Data from patients at 16 centers were collected for a multicenter retrospective study. Patients who underwent at least one RFA treatment for Barrett's esophagus and thereafter underwent further esophageal ESD for neoplasia recurrence were included. RESULTS: Data from 56 patients who underwent salvage ESD between April 2014 and November 2022 were collected. Immediate complications included one muscular tear (1.8%) treated with stent (Agree classification: grade IIIa). Two transmural perforations (3.6%; treated with clips) and five muscular tears (8.9%; two treated with clips) had no clinical impact and were not considered as adverse events. Seven patients (12.5%) developed strictures (grade IIIa), which were treated with balloon dilation. Histological analysis showed 36 adenocarcinoma, 17 high grade dysplasia, and 3 low grade dysplasia. En bloc and R0 resection rates were 89.3% and 66.1%, respectively. Resections were curative in 33 patients (58.9%), and noncurative in 22 patients (39.3%), including 11 "local risk" (19.6%) and 11 "high risk" (19.6%) resections. At the end of follow-up with a median time of 14 (0-75) months after salvage ESD, and with further endoscopic treatment if necessary (RFA, argon plasma coagulation, endoscopic mucosal resection, ESD), neoplasia remission ratio was 37/53 (69.8%) and the median remission time was 13 (1-75) months. CONCLUSION: In expert hands, salvage ESD was a safe and effective treatment for recurrence of Barrett's neoplasia after RFA treatment.

Disease burden of Barrett's esophagus across the Paris metropolitan area.

INTRODUCTION: The prevalence of Barrett's esophagus (BE) in France is unknown. However, the management of dysplastic BE in expert centers is recommended and reduces the risk of developing invasive adenocarcinoma. Our aim was to determine the burden of BE patients in the Paris Region. METHODS: We performed a retrospective study using the data from electronic medical records from the data warehouse of the 39 Greater Paris public hospitals (Entrepôt de données de santé de l' Assistance Publique- Hôpitaux de Paris) for the year 2018, and used natural language processing to search for occurrences of Barrett's esophagus in endoscopy and pathology reports. RESULTS: we observed a 2.2 % prevalence of Barrett's esophagus. Patients with Barrett's esophagus were older, more frequently males, with a hiatal hernia, proton pump inhibitor users, and less frequently infected by H. Pylori. Gastro-esophageal reflux symptoms were not more frequently encountered in Barrett's patients. Eleven percent of patients with Barrett's esophagus had dysplasia or adenocarcinoma. DISCUSSION: Over 200 000 patients with Barrett's esophagus are expected in the Paris Region, of which 11 % harbor dysplasia or adenocarcinoma. This data should be taken into account to tailor healthcare offer in France.

Management after local excision of small rectal cancers. Indications for completion total mesorectal excision and possible alternatives.

The treatment of superficial rectal cancers (local excision, or proctectomy with total mesorectal excision (TME) remains controversial. Endoscopy and endorectal ultrasonography are essential for the precise initial definition of these small cancers. During endoscopy, the depth of the lesion can be estimated using virtual chromoendoscopy with magnification, thereby aiding the assessment of the possibilities of local excision. Current international recommendations indicate completion proctectomy after wide local excision for cases where the pathologic examination reveals poorly-differentiated lesions, lymphovascular invasion, grade 2 or 3 tumor budding, and incomplete resection. But debate persists regarding whether the depth of submucosal invasion can accurately predict the risk of lymph node spread. Recent data from the literature suggest that the depth of submucosal invasion should no longer, by itself, be an indication for additional oncological surgery. Adjuvant radio-chemotherapy could be an alternative to completion proctectomy in patients with pT1 rectal cancer and unfavorable histopathological criteria. A Dutch randomized controlled trial is underway to validate this strategy.