Clinical practice of endoscopic submucosal dissection for early colorectal neoplasms by a colonoscopist with limited gastric experience. Gastroenterol Res Pract. 2013;2013:262171. [PMID: 24391666 PMCID: PMC3874345 DOI: 10.1155/2013/262171]

Endoscopic resection of gastrointestinal tumors: Training levels and professional roles explored

In this editorial, we provide commentary on a recently published study by Zhao et al in the World Journal of Gastrointestinal Oncology. The study discusses the clinical characteristics of patients undergoing endoscopic resection for gastric cancers. We feel it is important to engage our endoscopy community in a discussion on the current evidence in the literature on the necessary number of cases for training in endoluminal surgery techniques, particularly endoscopic submucosal dissection. This includes the latest recommendations from the European Society of Gastrointestinal Endoscopy, as well as a summary of key studies on the learning curve for these techniques. Additionally, we explore the impact of an endoscopist's specialty on endoscopy outcomes, drawing from current evidence in the literature to shape our perspective in this evolving field.

Systematic literature review of learning curves for colorectal polyp resection techniques in lower gastrointestinal endoscopy

AIM

The performance of therapeutic procedures in lower gastrointestinal endoscopy (LGI) can be challenging and carries an increased risk of adverse events. There is increasing demand for the training of endoscopists in these procedures, but limited guidelines exist concerning procedural competency. The aim of this study was to assess the learning curves for LGI polypectomy, colorectal endoscopic mucosal resection (EMR) and colorectal endoscopic submucosal dissection (ESD).

METHOD

A systematic review of electronic databases between 1946 and September 2019 was performed. Citations were included if they reported learning curve data. Outcome measures that defined the success of procedural competency were also recorded.

RESULTS

A total of 34 out of 598 studies met the inclusion criteria of which 28 were related to ESD, three to polypectomy and three to EMR. Outcome measures for polypectomy competency (en bloc resection, delayed bleeding and independent polypectomy rate) were achieved after completion of between 250 and 400 polypectomies and after 300 colonoscopies. EMR outcome measures, including complete resection and recurrence, were achieved variably between 50 and 300 procedures. Outcome measures for ESD included efficiency (resection rates and procedural speed) and safety (adverse events). En bloc resection rates of over 80% and R0 resection rates of over 70% were achieved at 20-40 cases and procedural speed increased after 30 ESD cases. Competency in safety metrics was variably achieved at 20-200 cases.

CONCLUSION

There is a paucity of data on learning curves in LGI polypectomy, EMR and ESD. Despite limited evidence, we have identified relevant outcome measures and threshold numbers for the most common LGI polyp resection techniques for potential inclusion in training programmes/credentialing guidelines.

A task and performance analysis of endoscopic submucosal dissection (ESD) surgery

BACKGROUND

ESD is an endoscopic technique for en bloc resection of gastrointestinal lesions. ESD is a widely-used in Japan and throughout Asia, but not as prevalent in Europe or the US. The procedure is technically challenging and has higher adverse events (bleeding, perforation) compared to endoscopic mucosal resection. Inadequate training platforms and lack of established training curricula have restricted its wide acceptance in the US. Thus, we aim to develop a Virtual Endoluminal Surgery Simulator (VESS) for objective ESD training and assessment. In this work, we performed task and performance analysis of ESD surgeries.

METHODS

We performed a detailed colorectal ESD task analysis and identified the critical ESD steps for lesion identification, marking, injection, circumferential cutting, dissection, intraprocedural complication management, and post-procedure examination. We constructed a hierarchical task tree that elaborates the order of tasks in these steps. Furthermore, we developed quantitative ESD performance metrics. We measured task times and scores of 16 ESD surgeries performed by four different endoscopic surgeons.

RESULTS

The average time of the marking, injection, and circumferential cutting phases are 203.4 (σ: 205.46), 83.5 (σ: 49.92), 908.4 s. (σ: 584.53), respectively. Cutting the submucosal layer takes most of the time of overall ESD procedure time with an average of 1394.7 s (σ: 908.43). We also performed correlation analysis (Pearson's test) among the performance scores of the tasks. There is a moderate positive correlation (R = 0.528, p = 0.0355) between marking scores and total scores, a strong positive correlation (R = 0.7879, p = 0.0003) between circumferential cutting and submucosal dissection and total scores. Similarly, we noted a strong positive correlation (R = 0.7095, p = 0.0021) between circumferential cutting and submucosal dissection and marking scores.

CONCLUSIONS

We elaborated ESD tasks and developed quantitative performance metrics used in analysis of actual surgery performance. These ESD metrics will be used in future validation studies of our VESS simulator.

Colorectal endoscopic submucosal dissection: a systematic review and meta-analysis

Background and study aims: Endoscopic submucosal dissection (ESD) is an advanced endoscopic technique that allows en-bloc resection of gastrointestinal tumor. We systematically review the medical literature in order to evaluate the safety and efficacy of colorectal ESD. Patients and methods: We performed a comprehensive literature search of MEDLINE, EMBASE, Ovid, CINAHL, and Cochrane for studies reporting on the clinical efficacy and safety profile of colorectal ESD. Results: Included in this study were 13833 tumors in 13603 patients (42 % female) who underwent colorectal ESD between 1998 and 2014. The R0 resection rate was 83 % (95 % CI, 80 - 86 %) with significant between-study heterogeneity (P < 0.001) which was partly explained by difference in continent (P = 0.004), study design (P = 0.04), duration of the procedure (P = 0.009), and, marginally, by average tumor size (P = 0.09). Endoscopic en bloc and curative resection rates were 92 % (95 % CI, 90 - 94 %) and 86 % (95 % CI, 80 - 90 %), respectively. The rates of immediate and delayed perforation were 4.2 % (95 % CI, 3.5 - 5.0 %) and 0.22 % (95 % CI, 0.11 - 0.46 %), respectively, while rates of immediate and delayed major bleeding were 0.75 % (95 % CI, 0.31 - 1.8 %) and 2.1 % (95 % CI, 1.6 - 2.6 %). After an average postoperative follow up of 19 months, the rate of tumor recurrence was 0.04 % (95 % CI, 0.01 - 0.31) among those with R0 resection and 3.6 % (95 % CI, 1.4 - 8.8 %) among those without R0 resection. Overall, irrespective of the resection status, recurrence rate was 1.0 % (95 % CI, 0.42 - 2.1 %). Conclusions: Our meta-analysis, the largest and most comprehensive assessment of colorectal ESD to date, showed that colorectal ESD is safe and effective for colorectal tumors and warrants consideration as first-line therapy when an expert operator is available.

Endoscopic submucosal dissection

ESD is an established effective treatment modality for premalignant and early-stage malignant lesions of the stomach, esophagus, and colorectum. Compared with EMR, ESD is generally associated with higher rates of en bloc, R0, and curative resections and a lower rate of local recurrence. Oncologic outcomes with ESD compare favorably with competing surgical interventions, and ESD also serves as an excellent T-staging tool to identify noncurative resections that will require further treatment. ESD is technically demanding and has a higher rate of adverse events than most endoscopic procedures including EMR. As such,sufficient training is critical to ensure safe conduct and high-quality resections. A standardized training model for Western endoscopists has not been clearly established,but will be self-directed and include courses, animal model training, and optimally an observership at an expert center.Numerous dedicated ESD devices are now available in the United States from different manufacturers. Although the use of ESD in the United States is increasing, issues related to technical difficulty, limited training opportunities and mentors, risk of adverse events, long procedure duration,and suboptimal reimbursement may limit ESD adoption in the United States to a modest number of academic referral centers for the foreseeable future.

Impact of formal training in endoscopic submucosal dissection for early gastrointestinal cancer: A systematic review and a meta-analysis

AIM: To summarize the clinical impact of a formal training for the effectiveness and safety of endoscopic submucosal dissection for gastrointestinal cancer.

METHODS: We searched databases including PubMed, EMBASE and the Cochrane Library and Science citation Index updated to August 2014 to include eligible articles. In the Meta-analysis, the main outcome measurements were en bloc resection rate, local recurrence rate (R0) and the incidence of procedure-related complications (perforation, bleeding).

RESULTS: En bloc resection was high for both, dissecting stomach tumors with an overall percentage of 93.2% (95%CI: 90.5-95.8) and dissecting colorectal tumors with an overall percentage of 89.4% (95%CI: 85.1-93.7). Although the number of studies reporting R0 resection (the dissected specimen was revealed free of tumor in both vertical and lateral margins) was small, the overall estimates for R0 resection were 81.4% (95%CI: 72-90.8) for stomach and 85.9% (95%CI: 77.5-95.5) for colorectal tumors, respectively. The analysis showed that the percentage of immediate perforation and bleeding were very low; 4.96 (95%CI: 3.6-6.3) and 1.4% (95%CI: 0.8-1.9) for colorectal tumors and 3.1% (95%CI: 2.0-4.1) and 4.8% (95%CI: 2.8-6.7) for stomach tumors, respectively.

CONCLUSION: In order to obtain the same rate of success of the analyzed studies it is a necessity to create training centers in the western countries during the “several years” of gastroenterology residence first only to teach EGC diagnose and second only to train endoscopic submucosal dissection.