Learning curve for endoscopic submucosal dissection of esophageal neoplasms

Artificial intelligence-based automated surgical workflow recognition in esophageal endoscopic submucosal dissection: an international multicenter study (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) is a crucial yet challenging multi-phase procedure for treating early gastrointestinal cancers. This study developed an artificial intelligence (AI)-based automated surgical workflow recognition model for esophageal ESD and proposed an innovative training program based on esophageal ESD videos with or without AI labels to evaluate its effectiveness for trainees.

METHODS

We retrospectively analyzed complete ESD videos collected from seven hospitals worldwide between 2016 and 2024. The ESD surgical workflow was divided into 6 phases and these videos were divided into five datasets for AI model. Trainees were invited to participate in this multimedia training program and were assigned to the AI or control group randomly. The performance of the AI model and label testing were evaluated using the accuracy.

RESULTS

A total of 195 ESD videos (782,488 s, 9268 phases) were included. The AI model achieved accuracy of 92.08% (95% confidence interval (CI), 91.40-92.76%), 91.71% (95% CI 90.11-93.31%), and 89.84% (95% CI 87.42-92.25%) in the training, internal, and external test dataset (esophagus), respectively. It also achieved acceptable results in the external test dataset (stomach, colorectum). For the training program, the overall label testing accuracy of the AI group learning ESD videos with AI labels was 88.73 ± 2.97%, significantly higher than the control group without AI labels (81.51 ± 4.63%, P < 0.001).

CONCLUSION

The AI model achieved high accuracy in the large ESD video datasets. The training program improves understanding of the complexity of ESD workflow and demonstrates the program's effectiveness for trainees.

Endoscopic Resections for Barrett's Neoplasia: A Long-Term, Single-Center Follow-Up Study

Background and Objectives: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are both well-established and effective treatments for dysplasia and early cancer in Barrett's esophagus (BE). This study aims to compare the short- and long-term outcomes associated with these procedures in treating Barrett's neoplasia. Materials and Methods: This single-center retrospective cohort study included 95 patients, either EMR (n = 67) or ESD (n = 28), treated for Barrett's neoplasia at Sahlgrenska University Hospital between 2004 and 2019. The primary outcome was the complete (en-bloc) R0 resection rate. Secondary outcomes included the curative resection rate, additional endoscopic resections, adverse events, and overall survival. Results: The complete R0 resection rate was 62.5% for ESD compared to 16% for EMR (p < 0.001). The curative resection rate for ESD was 54% versus 16% for EMR (p < 0.001). During the follow-up, 22 out of 50 patients in the EMR group required additional endoscopic resections (AERs) compared to 3 out of 21 patients in the ESD group (p = 0.028). There were few adverse events associated with both EMR and ESD. In both the stratified Kaplan-Meier survival analysis (Log-rank test, Chi-square = 2.190, df = 1, p = 0.139) and the multivariate Cox proportional hazards model (hazard ratio of 0.988; 95% CI: 0.459 to 2.127; p = 0.975), the treatment group (EMR vs. ESD) did not significantly impact the survival outcomes. Conclusions: Both EMR and ESD are effective and safe treatments for BE neoplasia with few adverse events. ESD resulted in higher curative resection rates with fewer AERs, indicating its potential as a primary treatment modality. However, the survival analysis showed no difference between the methods, highlighting their comparable long-term outcomes.

Intelligent surgical workflow recognition for endoscopic submucosal dissection with real-time animal study

Recent advancements in artificial intelligence have witnessed human-level performance; however, AI-enabled cognitive assistance for therapeutic procedures has not been fully explored nor pre-clinically validated. Here we propose AI-Endo, an intelligent surgical workflow recognition suit, for endoscopic submucosal dissection (ESD). Our AI-Endo is trained on high-quality ESD cases from an expert endoscopist, covering a decade time expansion and consisting of 201,026 labeled frames. The learned model demonstrates outstanding performance on validation data, including cases from relatively junior endoscopists with various skill levels, procedures conducted with different endoscopy systems and therapeutic skills, and cohorts from international multi-centers. Furthermore, we integrate our AI-Endo with the Olympus endoscopic system and validate the AI-enabled cognitive assistance system with animal studies in live ESD training sessions. Dedicated data analysis from surgical phase recognition results is summarized in an automatically generated report for skill assessment.

Management of esophageal neoplasms by endoscopic submucosal dissection: experience over 100 consecutive procedures

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD) is currently considered the first-line treatment for the eradication of superficial neoplasms of the esophagus in Eastern countries. However, in the West, particularly in Latin America, the experience with esophageal ESD is still limited because of the high technical complexity required for its execution. This study aimed to present the results of the clinical application of ESD to manage superficial esophageal neoplasms in a Latin American center in over 100 consecutive cases.

METHODS

This retrospective study included consecutive patients who underwent endoscopic ESD for superficial esophageal neoplasms between 2009 and 2022. The following clinical outcomes were assessed: en bloc, complete, and curative resection rates, local recurrence, adverse events, and procedure-related mortality.

RESULTS

Esophageal ESD was performed mainly for squamous cell carcinoma (66.6%), high-grade intraepithelial neoplasia (17.1%), and adenocarcinoma (11.4%). En bloc and complete resection rates were 96.2% and 81.0%, respectively. The curative resection rate was 64.8%. Adverse events occurred in six cases (5.7%). Endoscopic follow-up was performed for an average period of 29.7 months.

CONCLUSION

ESD performed by trained operators is feasible, safe, and clinically effective for managing superficial neoplastic lesions of the esophagus in Latin America.

Endoscopic Resection of Residual or Recurrent Lesions after Circumferential Radiofrequency Ablation for Flat Superficial Esophageal Squamous Cell Neoplasias

The optimal treatment of residual/recurrent superficial esophageal squamous cell neoplasias (SESCNs) after circumferential radiofrequency (RFA) remains unclear. We aimed to report the efficacy and safety of endoscopic resection (ER) of residual/recurrent SESCNs after RFA. Patients who underwent circumferential RFA with residual/recurrent SESCNs and were treated with ER were retrospectively collected. SESCN patients treated with primary endoscopic submucosal dissection (ESD) served as the control group. Eleven patients who underwent RFA had a total of 17 residual (n = 8) or recurrent (n = 9) SESCNs and were treated for ER. EMR failed to remove one residual SESCN. Of the 16 resected specimens, 10 were high-grade intraepithelial neoplasia (HGIN) and six were cancer. Eight cases had neoplasia extending to esophageal ducts/submucosal glands (SMGs). The pathological results may imply three possible routes in which residual/recurrent SESCNs occurred: HGIN without ductal/SMG involvement (37.5%), HGIN with ductal/SMG involvement (25.0%), and SCC with muscularis mucosae or deeper involvement (37.5%). Compared with the control group, the study group had similar procedural speed, en bloc resection rate, R0 resection rate, and complication rate. In conclusion, the safety and efficacy of post-RFA ESD were similar to those of primary ESD. ESD should be the treatment of choice for residual/recurrent SESCNs after initial RFA.

LEARNING CURVE IN ESOPHAGEAL ENDOSCOPIC SUBMUCOSAL DISSECTION BY WESTERN ENDOSCOSPISTS TRAINED IN JAPAN: EXPERIENCE IN LATIN AMERICA

•This study aimed to assess the learning curve effect on patient's clinical outcome for EESD. Retrospective observational study, enrolling patients that underwent EESD from 2009 to 2021, divided in 2 groups. Mean procedure time was 111.8 min and 103.6 min for T1 and T2, respectively (P=0.004). The learning curve in esophageal ESD could be overcomed effectively and safely by an adequately trained Western endoscopist. Background - Esophageal endoscopic submucosal dissection (EESD) is a complex and time-consuming procedure at which training are mainly available in Japan. There is a paucity of data concerning the learning curve to master EESD by Western endoscopists. Objective - This study aimed to assess the learning curve effect on patient's clinical outcome for EESD. Methods - This is a retrospective observational study. Enrolling patients that underwent EESD from 2009 to 2021. The analysis was divided into two periods; T1: case 1 to 49 and T2: case 50 to 98. The following features were analyzed for each group: patients and tumors characteristics, en-bloc, complete and curative resection rates, procedure duration and adverse events rate. Results - Ninety-eight EESD procedures were performed. Mean procedure time was 111.8 min and 103.6 min for T1 and T2, respectively (P=0.004). En bloc resection rate was 93.8% and 97.9% for T1 and T2, respectively (P=0.307). Complete resection rate was 79.5% and 85.7% for T1 and T2, respectively (P=0.424). Curative resection rate was 65.3% and 71.4% for T1 and T2, respectively (P=0.258). Four patients had complications; three during T1 period and one during T2 period. Overall mortality rate: 0%. Conclusion - The esophageal endoscopic submucosal dissection could be performed effectively and safely by an adequately trained Western endoscopist.

Synchronous Head and Neck Cancer and Superficial Esophageal Squamous Cell Neoplasm: Endoscopic Treatment or No Treatment for the Superficial Esophageal Neoplasm

There are no studies on treating synchronous head and neck cancer (HNC) and superficial esophageal squamous cell neoplasm (SESCN). We aimed to report the outcomes of endoscopic resection (ER) and no treatment (NT) of SESCN in patients with synchronous HNC and SESCN (SHNSESCN). This retrospective study included 47 patients with SHNSESCN. Treatment for SESCN was ER (n = 30) or NT (n = 17). The ER group had significantly lower Charlson comorbidity index scores and a higher proportion of Eastern Cooperative Oncology Group performance status (ECOG PS) scores ≤1. The location and stage of the two tumors did not differ significantly between the groups. The 1-year, 3-year, and 5-year OS rates of the ER group were significantly better than those in the NT group. Treatment-related morbidity and mortality were not significantly different between the two groups. In the subgroup analysis of synchronous advanced HNC and SESCN, ER for SESCN also had a higher OS rate. Multivariate analysis showed that ECOG PS score and HNC disease progression were the two independent indicators of OS. In conclusion, treatment of SESCN with ER is the recommended approach for patients with SHNSESCN, but further randomized controlled trials are needed to confirm this.

Training in Endoscopic Submucosal Dissection in the United States: The Current Paradigm

Endoscopic submucosal dissection (ESD) training in Japan is pursued through a designated master-apprentice, organ-based stepwise training model. However, applying a similar program to the United States is not a practical strategy due to the significant differences in the training system and disease prevalence. To incorporate the ESD training into the current advanced endoscopy fellowship program, the use of recently developed techniques and technologies to improve the efficiency of ESD is ideal. The ESD training program in the United States should be prevalence-based, with increased involvement of trainees depending on their objectively assessed competency levels.

Factors of technical difficulty in conventional and traction-assisted esophageal endoscopic submucosal dissection

BACKGROUND

The traction assisted (TA) method has reduced the technical difficulty associated with esophageal endoscopic submucosal dissection (ESD). However, it is unclear which factors associated with difficulty have been improved by the TA-ESD method. We aimed to evaluate and compare difficulty factors between conventional and TA-ESD.

METHODS

We retrospectively enrolled patients treated by ESD from Apr 2010 to Jun 2014 for the conventional ESD cohort and from Jan 2016 to Dec 2019 for the TA-ESD cohort. Difficult cases were defined as; (1)  ≥ 120 min ESD procedure time, (2) intraoperative perforation, or (3) piecemeal resection. We explored and compared the factors associated with technical difficulty in each cohort.

RESULTS

The conventional and TA-ESD cohorts included 285 (299 lesions) and 387 (421 lesions) patients, respectively. For difficult cases, the conventional and TA-ESD cohorts had 91 (30%) and 71 (17%) lesions, respectively. Multivariate logistic regression showed that ≥ 30 mm lesion length (odds ratio (OR) 6.85, 95% confidence interval (CI) 3.47-13.50), lower esophagus (OR 2.37, 95% Cl 1.34-4.21), > 1/2 circumference (OR 2.26, 95% CI 1.28-3.99), and left wall (OR 2.72, 95% CI 1.42-5.20) in the conventional ESD cohort, and ≥ 30 mm lesion length (21.30, 95% CI 4.75-95.30), lower esophagus (OR 3.05, 95% CI 1.52-6.13), and > 1/2 circumference (OR 6.40, 95% CI 3.06-13.40) in the TA-ESD cohort, were independently associated with technical difficulty.

CONCLUSIONS

TA-ESD can reduce the difficulty in cases including lesions in the left wall; however, cases in the lower esophagus and large lesions were still difficult to simplify.

cT1N0M0 Esophageal Squamous Cell Carcinoma Invades the Muscularis Mucosa or Submucosa: Comparison of the Results of Endoscopic Submucosal Dissection and Esophagectomy

BACKGROUND

Endoscopic submucosal dissection (ESD) combined with selective adjuvant chemoradiotherapy may be a new treatment option for cT1N0M0 esophageal squamous cell carcinoma (ESCC) invading muscularis mucosa or submucosa (pT1a-M3/pT1b). We aim to report the effectiveness of this treatment by comparing the results of esophagectomy.

METHODS

This retrospective single-center study included 72 patients with pT1a-M3/pT1b ESCC who received ESD combined with selective adjuvant chemoradiotherapy (n = 40) and esophagectomy (n = 32). The main outcome comparison was overall survival (OS). The secondary outcomes were treatment-related events, including operation time, complication rate, and length of hospital stay. Disease-specific survival (DSS) and progression-free survival (PFS) were also evaluated.

RESULTS

There were no significant differences in the rates of OS, DSS, and PFS between the two groups (median follow-up time: 49.2 months vs. 50.9 months); these were also the same in the subgroup analysis of pT1b ESCC patients. In the ESD group, the procedure time, overall complication rates, and length of hospital stay were significantly reduced. However, the metachronous recurrence rate was significantly higher. In a multivariate analysis, tumor depth and R0 resection were the independent factors associated with OS.

CONCLUSIONS

ESD combined with selective adjuvant chemoradiotherapy can be an alternative treatment to esophagectomy for cT1N0M0 ESCC invading muscularis mucosa or submucosa.

Safety and effectiveness of mucosal traction using a snare combined with endoclips to assist the resection of esophageal intraepithelial neoplasia: a propensity score matching analysis

Currently, the reports on esophageal endoscopic submucosal dissection (ESD) assisted by traction with a snare are rare. Because a snare is a commonly used endoscopic accessory and is easily available, its application in mucosal traction is worth exploring. The present study aims to evaluate the safety and effectiveness of snare-endoclip traction-assisted ESD for esophageal intraepithelial neoplasia. Cases of esophageal intraepithelial neoplasia resected using ESD in the Digestive Endoscopy Center of Guangzhou Nanfang Hospital, China from June 2013 to March 2019 were retrospectively analyzed. The procedure of snare-endoclip traction-assisted ESD was compared with nontraction-assisted ESD by using a propensity score matching analysis. Operation time, en bloc and R0 resection, intra- and postoperative complications, and surgery-related costs were mainly evaluated. Overall, 99 cases of esophageal intraepithelial neoplasia under tissue biopsy were included in the present study. Further, 22 exact matched pairs were obtained. There were no differences in en bloc and R0 resection rates, intra- and postoperative complications, and costs of disposable surgical accessories between the traction group and the nontraction group. However, median operation time showed a significant difference: traction group, 50.0 min (range, 20-100 min); nontraction group, 70.0 min (range, 35-133 min), P=0.012. In conclusion, snare-endoclip traction-assisted ESD for esophageal intraepithelial neoplasia was safe and shortened operation time in the study, thereby improving the efficiency of ESD. Despite the additional use of a snare and endoclips for traction, the total costs of endoscopic accessories seemed not to be increased.

ENDOSCOPIC SUBMUCOSAL DISSECTION WITH CIRCUMFERENTIAL INCISION VERSUS TUNNELING METHOD FOR TREATMENT OF SUPERFICIAL ESOPHAGEAL CANCER

BACKGROUND

Endoscopic submucosal dissection (ESD) of esophageal superficial neoplasm is associated with a high en bloc R0 resection rate and low recurrence.

OBJECTIVE

We aim to compare the performance and clinical outcomes of ESD via ESD after circumferential incision (ESD-C) versus submucosal tunneling (ESD-T).

METHODS

Single-center retrospective analysis of all consecutive patients who underwent ESD for superficial esophageal cancer, between 2009 and 2018. ESD-T was defined as the technique of making the mucosal incisions followed by submucosal tunneling in the oral to anal direction. ESD-C consisted of completing a circumferential incision followed by ESD. Main study outcomes included en bloc and R0 resection rates. Secondary outcomes included procedural characteristics, curative resection rate, local recurrence and adverse events.

RESULTS

A total of 65 procedures (23 ESD-T and 42 ESD-C) were performed for ESCC (40; 61.5%) and BE-neoplasia (25; 38.5%). There were no statistically significant differences between patients who underwent ESD-T versus ESD-C in en bloc (91.3% vs 100%, P=0.12), R0 (65.2% vs 78.6%, P=0.24), curative resection rates (65.2% vs 73.8%, P=0.47) and mean procedure time (118.7 min with vs 102.4 min, P=0.35). Adverse events for ESD-T and ESD-C were as follows: bleeding (0 versus 2.4%; P=0.53), perforation (4.3% vs 0; P=0.61), esophageal stricture (8.7% versus 9.5%; P=0.31). Local recurrence was encountered in 8.7% after ESD-T and 2.4% after ESD-C (P=0.28) at a mean follow-up of 8 and 2.75 years, respectively (P=0.001).

CONCLUSION

ESD-T and ESD-C appear to be equally effective with similar safety profiles for the management of superficial esophageal neoplasms.

Endoscopic Submucosal Dissection for Upper Gastrointestinal Neoplasia-a North American Perspective

OBJECTIVES

Organ-sparing endoscopic submucosal dissection (ESD) is an acceptable treatment strategy for superficial neoplastic lesions of the esophagus and stomach. The adoption of this technique has lagged in North America compared with Asia, and we sought to report on our experiences with ESD for upper GI neoplasia.

METHODS

A prospectively entered database of all patients undergoing endoscopic resection of esophageal and gastric neoplasia at McGill University from 2009 to 2019 was queried for those who received ESD.

RESULTS

A total of 103 consecutive ESDs were identified from 2009 to 2019. Seventy-one (69%) patients were male and the median age was 72 (range: 38-90). Sixty-one (59%) cases were esophageal and 42 (41%) gastric. Forty-nine (48%) were performed in the endoscopy suite under local sedation only. Perforation occurred in 9 patients (7 esophageal and 2 stomach), of which 3 required operative repair. Histology was principally invasive carcinoma (79, 77%), with 17 (16%) dysplastic lesions (e.g., HGD), 1 (1%) neuroendocrine tumor, and 7 (7%) benign lesions. En bloc resection was achieved in 90 (87%), and the complete resection rate was 74 (72%), with 51 (50%) of procedures fulfilling the criteria for curative resection. At medium of 23-month (2-199) follow-up of these 51 curative resections, one case of recurrent carcinoma was found at follow-up and was managed with repeat endoscopic resection. Non-curative ESDs were found 45 (R1 resection = 29: risk of lymph node metastasis = 16), 21 had active surveillance, and 24 were resected.

CONCLUSION

ESD is a viable, effective, and safe therapeutic and staging modality for superficial lesions of the stomach and esophagus.

Analysis of the learning curve for artificial pneumothorax during an endoscopic McKeown-type resection of oesophageal carcinoma

Background

Due to the large trauma caused by conventional open surgery, minimally invasive esophageal cancer surgery has been gradually carried out, and there is no report on the learning curve for artificial pneumothorax during an endoscopic McKeown-type resection of oesophageal carcinoma.

Methods

Forty cases of McKeown resection of oesophageal carcinoma with artificial pneumothorax that were completed by the same operator between December 2017 and August 2019 were analysed. The patients were divided into four groups (A, B, C, D) of 10 cases each according to the order of operation. The operation time, intraoperative blood loss, total lymph nodes and left recurrent laryngeal nerve lymph nodes resection, conversion rate, complication rate and hospitalization time were compared between the four groups.

Results

The operation time of the four groups were as follows: A, 243.2±44.1 min; B, 265.0±59.3 min; C, 255.8±41.7 min; D, 201.0±16.2 min, there were significant difference in terms of the operation time between group A, group B, group C and group D (P<0.05). Moreover, groups A and C all differed significantly from group D in the number of dissected left recurrent laryngeal nerve lymph nodes. However, no significant inter-group differences were observed in the number of trans-laparotomy and trans-thoracotomy, number of dissected total lymph nodes, intraoperative blood loss, incidence of postoperative complications and postoperative length of hospital stay (P>0.05).

Conclusions

Artificial pneumothorax during an endoscopic McKeown-type resection of oesophageal carcinoma required a learning curve of approximately 30 cases.

The effect of scissor-type versus non-scissor-type knives on the technical outcomes in endoscopic submucosal dissection for superficial esophageal cancer: a multi-center retrospective study

The Clutch Cutter was invented as a scissor-type knife for endoscopic submucosal dissection (ESD) of gastrointestinal neoplasms. ESD with the scissor-type knife (ESD-S) may be considered a technically easier procedure than ESD with non-scissor-type knives (ESD-NS). Therefore, this study aimed to compare the technical outcomes of ESD-S with those of ESD-NS for superficial esophageal cancer. This was a multicenter retrospective study. Patients with superficial esophageal cancer treated with ESD between October 2015 and March 2018 at three hospitals were retrospectively reviewed. The ESD-S group had 48 patients and the ESD-NS group had 114 patients. A propensity score matching analysis was performed to compensate for the confounding bias between both groups. Multivariate analyses and propensity score matching were used to adjust for age, sex, the tumor size, tumor location, tumor depth, degree of tumor circumference, operator level, usage of the traction method, and the sedation method. The primary outcome was the procedure time of the ESD. Secondary outcomes were the rate of en-bloc/complete resection and the rate of complications including perforation, delayed bleeding, and stricture. Propensity score matching analysis provided 36 matched pairs. Median procedure time in the ESD-S group was significantly shorter than that in the ESD-NS group (44.0 min vs. 66.5 min, P = 0.020). In addition, the treatment outcomes were similar in both groups (en-bloc resection: 100% vs. 97.2%, P = 1; complete resection: 88.9% vs. 86.1%, P = 1; curative resection: 80.6% vs. 77.8%, P = 1; perforation: 0% vs. 5.6%, P = 0.49; delayed bleeding: 0% in both groups; stricture: 2.8% vs. 8.3%, P = 0.61). ESD-S was associated with a shorter procedure time than ESD-NS, without an increase in the incidence of complications. Therefore, the scissor-type knife should be considered as an endo-knife for ESD of superficial esophageal cancers.

Introduction of gastric endoscopic submucosal dissection and skill acquisition in a regional hospital

Background and Aim

Endoscopic submucosal dissection (ESD) is standard treatment for early gastric cancer. With aging of the population in Japan being more pronounced in rural areas, the availability of ESD at regional hospitals is becoming important. Here, we assessed the learning curve of one physician for skill acquisition in gastric ESD.

Methods

The subjects were 34 patients (38 lesions) who underwent gastric ESD at a regional hospital between October 2014 and March 2017 and 15 patients (15 lesions) who underwent the procedure at a university hospital between April 2017 and April 2018. The resection periods of the first 19 lesions and subsequent 19 lesions at the regional hospital were defined as the first and seconds periods, and the resection period of 15 lesions at the university hospital was defined as the third period. The learning curve across the three periods was assessed using the cumulative sum analysis method.

Results

The resection speed in the first, second, and third periods were 6.4 ± 4.1, 6.9 ± 3.4, and 9.4 ± 5.4 mm²/min, respectively (not significant). The slope of the learning curve began to increase at the 30th patient. The en bloc resection and curative resection rates did not differ significantly among the three periods. There were no serious procedure‐related complications.

Conclusion

This study showed that the introduction of gastric ESD at a regional hospital is possible, and that a certain skill level was acquired by the 30th patient. Furthermore, with careful patient selection, favorable results can be obtained and procedural safety ensured.

Adjuvant therapy for pT1a-m3/pT1b esophageal squamous cell carcinoma after endoscopic resection: Esophagectomy or chemoradiotherapy? A critical review

Endoscopic resection (ER) combined with adjuvant therapy appears to be a new treatment for esophageal squamous cell cancers (ESCC) invading to deep mucosa (pT1a-m3) or submucosa (pT1b). Adjuvant therapy can take the form of esophagectomy or chemoradiotherapy (CRT), but it is unclear which treatment is better. This review is to explore the outcomes of adjuvant therapy between esophagectomy and CRT for the treatment of pT1a-m3/pT1b ESCC after ER. Ten relevant studies with a total of 285 patients were included. The reported 5-year overall survival rates ranged between 90-100 % for ER-esophagectomy and 75-85 % for ER-CRT. ESCC with the invasion of ≥ sm2 combined with lymphovascular involvement was associated with a high-risk of relapse in patients receiving ER-CRT, but not in ER-esophagectomy. In conclusion, patients with a high-risk of relapse should be treated with ER-esophagectomy; ER-CRT may be used as an alternative treatment for patients with a nonhigh risk of relapse.

Endoscopic Submucosal Dissection for Esophageal Adenocarcinoma: A North American Perspective

BACKGROUND

Data are limited regarding the application of endoscopic submucosal dissection (ESD) in Western countries or for esophageal adenocarcinoma in any part of the world. We sought to review our experience employing ESD in patients with early esophageal cancer at a high volume North American esophageal cancer treatment center.

METHODS

A prospectively maintained database of all patients with esophageal cancer treated at the McGill University Health Center was used to identify ESDs performed for adenocarcinoma between 2012 and 2016. Patient demographics, pre-resection tumor characteristics, endoscopic resection technical variables, pathologic results, and short- and long-term outcomes were recorded.

RESULTS

Of 650 patients in the database, 26 underwent 27 procedures. The majority (67%) had pre-treatment EUS. There were no post-ESD bleeding events requiring re-intervention. Perforation occurred in 2/27 (7%), one of which required operative repair. Complete RO resection was achieved in 18/27(67%). Salvage laparoscopic esophagectomy was performed in six patients. At a median follow-up of 18.5 (7-35) months, cancer recurrence occurred in only one patient who subsequently underwent successful repeat ESD.

CONCLUSIONS

Although technically challenging, ESD represents a safe and effective treatment of early esophageal adenocarcinoma and has the potential to become a more important tool in management of these early lesions in Western countries.

Learning curve and clinical outcome of gastric endoscopic submucosal dissection performed by trainee operators

BACKGROUND

Although endoscopic submucosal dissection (ESD) represents a significant progress in therapeutic endoscopy, little is known about how trainees attain its technical proficiency. The aims of this study were to evaluate the learning curve and clinical outcomes of gastric ESD performed by trainee endoscopists.

METHODS

Between April 2009 and March 2014, 334 gastric ESD procedures were performed by seven trainees (42-50 consecutive cases per trainee). The learning curve for gastric ESD was evaluated using the cumulative sum (CUSUM) method. Long-term outcomes were also analyzed.

RESULTS

The calculated CUSUM learning curve comprised three phases: Phase I (the initial 15 cases), Phase II (the middle 15 cases), and Phase III (the final 20 cases). The resection speed was 5.7 ± 3.2 min/cm² in Phase I, 4.7 ± 2.7 min/cm² in Phase II, and 4.3 ± 2.2 min/cm² in Phase III. The resection speed was significantly faster in Phase II than in Phase I (p = 0.019). The rate of self-completion reached more than 95% in Phases II and III. The overall complete resection rate was 95%, showing no significant differences between the three phases. Local recurrence was diagnosed in none of the patients during a median follow-up of 38 months.

CONCLUSIONS

For the trainees, 30 cases were required to attain a higher technical level of competence in gastric ESD. After the learning curve phase, trainee operators could be expected to complete the procedure successfully with favorable long-term outcomes.

Endoscopic Submucosal Dissection of Superficial Esophageal Neoplasms Is Feasible and Not Riskier for Patients with Liver Cirrhosis

BACKGROUND

Esophageal endoscopic submucosal dissection (ESD) has rarely been reported for the treatment of cirrhotic patients.

AIM

To report the results of ESD treatment of superficial esophageal neoplasms (SENs) for cirrhotic patients.

METHODS

Forty patients with 50 consecutive SENs undergoing 46 sessions of ESD were retrospectively reviewed. The cirrhotic group included eight patients (11 SENs) with liver cirrhosis consisting of six patients classified as Child-Pugh class A liver cirrhosis and two patients classified as class B liver cirrhosis. Four patients (6 SENs) had coexisting esophageal varices. Parameters were compared between the cirrhotic patients and the non-cirrhotic controls (32 patients, 39 SENs).

RESULTS

Platelet counts of the cirrhotic group were significantly lower, while international normalized ratio was significantly higher. When the cirrhotic group and non-cirrhotic group were compared, the mean tumor length (4 vs. 3.7 cm, p = 0.56) and median procedure time (15.1 vs. 11.5 min/cm², p = 0.30) were similar. The en bloc resection rates were 81.8 and 89.7 % (p = 0.60). Within the cirrhotic group, both lesions without en bloc resection were patients with esophageal varices. The rates of submucosal disease for the cirrhotic group and non-cirrhotic groups were 54.5 and 25.6 % (p = 0.064), respectively, while the R0 resection rates were 77.8 and 94.3 % (p = 0.16), respectively. The two lesions without R0 resection in cirrhotic group had positive vertical but not horizontal margins due to submucosal invasion. Intraprocedural bleeding occurred more frequently in cirrhotic patients than non-cirrhotic patients (18.2 vs. 0 %, p = 0.045). None of the patients suffered from esophageal perforation, postoperative bleeding, or death that was related to the ESD.

CONCLUSION

Esophageal ESD seems to be safely and can be effectively performed on cirrhotic patients, particularly those without severe liver dysfunction.

Esophageal Endoscopic Submucosal Dissection Assisted by an Overtube with a Traction Forceps: An Animal Study

Esophageal endoscopic submucosal dissection (ESD) is technically difficult. To make it safer, we developed a novel method using overtube with a traction forceps (OTF) for countertraction during submucosal dissection. We conducted an ex vivo animal study and compared the clinical outcomes between OTF-ESD and conventional method (C-ESD). A total of 32 esophageal ESD procedures were performed by four beginner and expert endoscopists. After circumferential mucosal incision for the target lesion, structured as the isolated pig esophagus 3 cm long, either C-ESD or OTF-ESD was randomly selected for submucosal dissection. All the ESD procedures were completed as en bloc resections, while perforation only occurred in a beginner's C-ESD procedure. The dissection time for OTF-ESD was significantly shorter than that for C-ESD for both the beginner and expert endoscopists (22.8 ± 8.3 min versus 7.8 ± 4.5 min, P < 0.001, and 11.3 ± 4.4 min versus 5.9 ± 2.5 min, P = 0.01, resp.). The frequency and volume of the submucosal injections were significantly smaller for OTF-ESD than for C-ESD (1.3 ± 0.6 times versus 2.9 ± 1.5 times, P < 0.001, and 5.3 ± 2.8 mL versus 15.6 ± 7.3 mL, P < 0.001, resp.). Histologically, muscular injury was more common among the C-ESD procedures (80% versus 13%, P = 0.009). Our results indicated that the OTF-ESD technique is useful for the safe and easy completion of esophageal ESD.

Endoscopic submucosal dissection for treatment of early esophageal cancer and precancerous lesions

Esophageal cancer is the eighth most common form of cancer worldwide. Advances in endoscopic therapy have resulted in dramatic changes in the way early esophageal cancer and precancerous lesions are managed. Endoscopic submucosal dissection (ESD) is a newly developed resection technique that is able to achieve a high R0 resection rate and a low local recurrence rate. Techniques of ESD have become established as standard methods of endoscopic resection. This review addresses some of the recent developments in the field of ESD for early esophageal cancer and precancerous lesions.