Endoscopic submucosal dissection--current success and future directions

Predictive factors associated with technical difficulty in colorectal endoscopic submucosal dissection: A Honam Association for the Study of Intestinal Disease (HASID) multicenter study

Colorectal endoscopic submucosal dissection (ESD) is a promising but challenging procedure. It is not widely performed due to its technical difficulty. We aimed to find the predictive factors associated with technical difficulty in colorectal ESD before the procedure. Clinical data from patients who underwent ESD for colorectal tumors in 5 hospitals in Honam province of South Korea between 2015 and 2020 were reviewed retrospectively. Technically difficult colorectal ESD procedure was defined in 3 points. Long procedure time (longer than 60 minutes), occurrence of perforation, and failure of en bloc resection. Factors associated with technically difficult ESD were included as main outcome measure. 1446 patients were identified and their data were analyzed. Median procedure time was 30.0 minutes and median long axis of the tumor was 20.1 mm. Technically difficult procedures including long procedure time were 231 cases (16.0%), perforation occurred in 34 cases (2.3%), and en bloc resection was done in 1292 cases (89.3%). Tumor size larger than 35 mm (odd ratio [OR]: 1.474, P = .047), central depression or ulceration in the lesion (OR: 1.474, P = .013), previous endoscopic mucosal resection (EMR) or polypectomy procedure (OR: 2.428, P = .020) were associated with technically difficult ESD. Descending colon-located tumor (OR: 5.355, P < .001), and use of IT knife (OR: 4.157, P = .003) were associated with perforation. Recognizing factors associated with technically difficult ESD can help in planning the ESD procedure beforehand.

Prognostic Implication of Lymphovascular Invasion in Early Gastric Cancer Meeting Endoscopic Submucosal Dissection Criteria: Insights from Radical Surgery Outcomes

BACKGROUND

The management of early gastric cancer (EGC) has witnessed a rise in the utilization of endoscopic submucosal dissection (ESD) as a treatment modality, although prognostic markers are needed to guide management strategies. This study investigates the prognostic implications of lymphovascular invasion (LVI) in ESD-eligible EGC patients, specifically its implications for subsequent radical surgery.

MATERIAL AND METHODS

A retrospective, multicenter study from two primary hospitals analyzed clinicopathological data from 1369 EGC patients eligible for ESD, who underwent gastrectomy at Shanghai Cancer Center and Huashan Hospital between 2009 and 2018. We evaluated the relationship between LVI and lymph node metastasis (LNM), as well as the influence of LVI on recurrence-free survival (RFS) and overall survival (OS).

RESULTS

We found a strong association between LVI and LNM (p < 0.001). Advanced machine learning approaches, including Random Forest, Gradient Boosting Machine, and eXtreme Gradient Boosting, confirmed the pivotal role of LVI in forecasting LNM from both centers. Multivariate analysis identified LVI as an independent negative prognostic factor for both RFS and OS, with hazard ratios of 4.5 (95% CI: 2.4-8.5, p < 0.001) and 4.4 (95% CI: 2.1-8.9, p < 0.001), respectively.

CONCLUSIONS

LVI is crucial for risk stratification in ESD-eligible EGC patients, underscoring the necessity for radical gastrectomy. Future research should explore the potential incorporation of LVI status into existing TNM staging systems and novel therapeutic strategies.

Lesion size affects the risk of technical difficulty in gastric endoscopic submucosal dissection

Current evidence shows an inter-country inconsistency in the effect of lesion size on the technical difficulty of gastric endoscopic submucosal dissection (ESD). We aimed to evaluate the specific correlation and quantify the ensuing risks. This retrospective study consisted of 405 ESD cases with gastric single lesion from April 2015 to April 2023. The correlation and risk prediction of lesion size with technical difficulty was explored to provide further clinical evidence. An additive generalized model and recursive algorithm were used to describe the non-linear association, and a linear two-piece regression was constructed to analyze the inflection point. Subgroup analysis and interaction were used to explore intergroup characteristics. Overall, difficult cases had larger lesion sizes, and the more significant the increase, the higher the risk of technical difficulty. In the full model, after adjusting for all covariates, each 1 mm, 3 mm, 5 mm, 7 mm, and one standard increase in lesion size increased the risk of technical difficulty by 8%, 26%, 42%, 72%, and 125%, respectively. There is a nonlinear positive correlation between lesion size and risk of technical difficulty, and the premeditated inflection point was 40 (mm) via two-piecewise linear regression and recursive algorithm. Subgroup analysis showed a stronger correlation between lesion size and difficult ESD in the upper site and submucosal fibrosis groups. Available evidence suggests that lesion size as a risk signal nonlinearly increases the technical difficulty of gastric ESD procedure, especially in cases of upper site and submucosal fibrosis, which deserves further investigation.

Effect of Sarcopenia on Pneumonia after Endoscopic Submucosal Resection in Patients Aged ≥65 Years: A Retrospective Study

We aimed to investigate the association between sarcopenia and incidence of pneumonia after endoscopic submucosal dissection (ESD) in patients aged ≥65 years. Patients with (n = 1571) and without sarcopenia (n = 1718) who underwent ESD for gastric neoplasm were included. Propensity score matching (PSM) was performed between the groups (n = 785) at a 1:1 ratio. The primary endpoint was the effect of sarcopenia on the incidence of pneumonia after ESD. Among the included patients, 2.2% (n = 71) developed pneumonia after ESD. After PSM, the incidence rate of pneumonia was significantly higher in patients with sarcopenia than that in patients without sarcopenia (p = 0.024). Sarcopenia and age ≥73 years were significantly associated with the incidence of pneumonia (sarcopenia and age <73 years, odd ratio (OR) = 1.22 [95% confidence interval (CI): 0.46-3.22]; sarcopenia and age ≥73 years, OR = 3.92 [95% CI: 1.79-8.74]). Patients with sarcopenia had an increased risk of developing pneumonia after ESD, even after adjusting for other factors, resulting in a higher incidence of leukocytosis and a longer duration of post-ESD hospitalization. The combination of sarcopenia and age ≥73 years could be an effective predictive factor for screening high-risk groups for pneumonia after ESD.

Nanodrugs systems for therapy and diagnosis of esophageal cancer

With the increasing incidence of esophageal cancer, its diagnosis and treatment have become one of the key issues in medical research today. However, the current diagnostic and treatment methods face many unresolved issues, such as low accuracy of early diagnosis, painful treatment process for patients, and high recurrence rate after recovery. Therefore, new methods for the diagnosis and treatment of esophageal cancer need to be further explored, and the rapid development of nanomaterials has brought new ideas for solving this problem. Nanomaterials used as drugs or drug delivery systems possess several advantages, such as high drug capacity, adjustably specific targeting capability, and stable structure, which endow nanomaterials great application potential in cancer therapy. However, even though the nanomaterials have been widely used in cancer therapy, there are still few reviews on their application in esophageal cancer, and systematical overview and analysis are deficient. Herein, we overviewed the application of nanodrug systems in therapy and diagnosis of esophageal cancer and summarized some representative case of their application in diagnosis, chemotherapy, targeted drug, radiotherapy, immunity, surgery and new therapeutic method of esophageal cancer. In addition, the nanomaterials used for therapy of esophageal cancer complications, esophageal stenosis or obstruction and oesophagitis, are also listed here. Finally, the challenge and the future of nanomaterials used in cancer therapy were discussed.

New traction method (traction ring) for colorectal endoscopic submucosal dissection

OBJECTIVES

Colorectal endoscopic submucosal dissection (ESD) is challenging because of the difficulty in adequately visualizing the submucosal layer. Many traction methods have been developed to facilitate submucosal dissection; however, they are not widely applied. Therefore, we designed a new traction device, a traction ring, and conducted this pilot study to evaluate its feasibility and safety for colorectal ESD.

METHODS

Twenty patients with colorectal lesions who underwent traction ring-assisted ESD were retrospectively included. The main outcomes included en bloc resection rate, R0 resection rate, procedure time, resection time, and intraoperative and postoperative complications.

RESULTS

The median procedure time was 74.5 min (range 35-269 min). The median resection time was 55 min (range 25-209 min). Application of the traction system accounted for only 2.7% of the entire procedure time. The en bloc resection rate was 95.0% (19/20), whereas the R0 resection rate was 90.0% (18/20). All traction rings were successfully set and retrieved. Significant intraoperative bleeding was not observed. One patient experienced perforation after treatment, but no further intervention was required. No delayed complications were observed within 1 month post-ESD.

CONCLUSION

Traction ring is an effective and safe method for colorectal ESD and can be used at any location in the colorectum.

Predictors of the difficulty for endoscopic resection of gastric gastrointestinal stromal tumor and follow-up data

BACKGROUND AND AIM

Gastrointestinal stromal tumors (GISTs) are among the most common submucosal tumors in the stomach that require therapeutic intervention. We aim to identify the predictors of technical difficulty during endoscopic resection of gastric GIST and to investigate follow-up outcomes.

METHODS

Patients with gastric GISTs were reviewed from June 2009 to June 2020 at Zhongshan Hospital. Clinical and pathological features, endoscopic procedure information, and follow-up data were collected and analyzed. A nomogram was developed and validated internally and externally.

RESULTS

A total of 628 GISTs were finally analyzed. The difficulty was experienced in 66 cases. GISTs size (2-3 cm: OR 2.431 P = 0.018 and > 3 cm: OR 9.765 P < 0.001), invasion depth beyond submucosal (MP: OR 2.280, P = 0.038 and MP-ex: OR 4.295, P = 0.002), and lack of experience (OR 2.075, P = 0.016) were independent risk factors of difficulty. The nomogram prediction model showed a bias-corrected C-index value of 0.778 and acquired an area under curve (AUC) of 0.756 on the external validation cohort. At the cut-off of 0.15, the nomogram's negative predictive value (NPV) and accuracy (ACC) were 94.9% and 79.8% in identifying non-difficult GISTs. Follow-up results showed that only five GIST patients had local recurrence after endoscopic resection.

CONCLUSIONS

Tumor size, invasion depth, and endoscopists' experience were risk factors for the difficulty of endoscopic GIST resection. Our nomogram provided a valuable tool for screening non-difficult GIST resection.

Prediction of technically difficult endoscopic submucosal dissection for large superficial colorectal tumors: a novel clinical score model

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is a promising technique for removing superficial GI tumors, but ESD is technically difficult. The aim of this study was to establish a clinical score model for grading technically difficult colorectal ESD.

METHODS

Data on patients, lesions, and outcomes of colorectal ESD at 2 centers were analyzed. The objective parameter of successful ESD within 60 minutes was set as an endpoint to evaluate the difficulty. Independent predictors of difficulty in the derivation cohort were identified by multiple logistic regression analysis and used to develop a clinical score. We validated the score model in the validation cohort.

RESULTS

The clinical score comprised tumor size of 30 to 50 mm (1 point) or ≥50 mm (2 points), at least two-thirds circumference of the lesion (2 points), location in the cecum (1 point), flexure (2 points) or dentate line (1 point), and laterally spreading tumor nongranular lesions (1 point). Areas under the receiver operator characteristic curves for the score model were comparable (derivation [.70] vs internal validation [.69] vs external validation [.69]). The probability of successful ESD within 60 minutes in easy (score = 0), intermediate (score = 1), difficult (score = 2-3), and very difficult (score ≥4) categories were 75.0%, 51.3%, 35.6%, and 3.4% in the derivation cohort; 73.3%, 47.9%, 31.8%, and 16.7% in the internal validation cohort; and 79.5%, 66.7%, 43.3%, and 20.0% in the external validation cohort, respectively.

CONCLUSIONS

This clinical score model accurately predicts the probability of successful ESD within 60 minutes and can be applied to grade the technical difficulty before the procedure.

Atypical Scar Patterns after Gastric Endoscopic Submucosal Dissection

Background/Aims: Endoscopic submucosal dissection (ESD) for gastric neoplasms is a widely performed procedure. Local recurrence is rare, but various post-ESD scars are encountered during follow-up endoscopy. Therefore, we investigated atypical scar patterns and evaluated the associated factors.Materials and Methods: Clinicopathologic and endoscopic reviews of gastric neoplasms treated with ESD from January 2009 to December 2015 were conducted. Atypical scar patterns were classified as irregular erythema, nodularity, or mucosal defect.Results: A total of 264 patients with 274 gastric neoplasms, including 201 adenomas and 73 early gastric cancers, were enrolled. The key endoscopic findings at the resection scar were defined on the basis of gross morphology as follows: irregular erythema, mucosal defect (erosion or ulcer), and nodularity. An irregular erythema scar pattern was associated with male sex, a nodularity scar pattern with smoking, and a mucosal defect scar pattern with infra-angle location (angle and antrum) and cancer. An irregular erythema with nodularity scar pattern was also associated with male sex. An irregular erythema with nodularity and mucosal defect scar pattern was associated with liver disease and chronic kidney disease.Conclusions: The atypical scar patterns after gastric ESD are associated with various clinicopathologic factors.

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.

Frontiers of Robotic Gastroscopy: A Comprehensive Review of Robotic Gastroscopes and Technologies

Simple Summary

With the rapid advancements of medical technologies and patients’ higher expectations for precision diagnostic and surgical outcomes, gastroscopy has been increasingly adopted for the detection and treatment of pathologies in the upper digestive tract. Correspondingly, robotic gastroscopes with advanced functionalities, e.g., disposable, dextrous and not invasive solutions, have been developed in the last years. This article extensively reviews these novel devices and describes their functionalities and performance. In addition, the implementation of artificial intelligence technology into robotic gastroscopes, combined with remote telehealth endoscopy services, are discussed. The aim of this paper is to provide a clear and comprehensive view of contemporary robotic gastroscopes and ancillary technologies to support medical practitioners in their future clinical practice but also to inspire and drive new engineering developments.

Abstract

Upper gastrointestinal (UGI) tract pathology is common worldwide. With recent advancements in robotics, innovative diagnostic and treatment devices have been developed and several translational attempts made. This review paper aims to provide a highly pictorial critical review of robotic gastroscopes, so that clinicians and researchers can obtain a swift and comprehensive overview of key technologies and challenges. Therefore, the paper presents robotic gastroscopes, either commercial or at a progressed technology readiness level. Among them, we show tethered and wireless gastroscopes, as well as devices aimed for UGI surgery. The technological features of these instruments, as well as their clinical adoption and performance, are described and compared. Although the existing endoscopic devices have thus far provided substantial improvements in the effectiveness of diagnosis and treatment, there are certain aspects that represent unwavering predicaments of the current gastroenterology practice. A detailed list includes difficulties and risks, such as transmission of communicable diseases (e.g., COVID-19) due to the doctor–patient proximity, unchanged learning curves, variable detection rates, procedure-related adverse events, endoscopists’ and nurses’ burnouts, limited human and/or material resources, and patients’ preferences to choose non-invasive options that further interfere with the successful implementation and adoption of routine screening. The combination of robotics and artificial intelligence, as well as remote telehealth endoscopy services, are also discussed, as viable solutions to improve existing platforms for diagnosis and treatment are emerging.

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.

Endoscopy robotics: Current and future applications

Many different types of endoscopy robot have been developed or are under development. Some of these innovative biotechnologies are dedicated to complex endoscopic procedures such as endoscopic submucosal dissection whereas others are purely diagnostic. In endoscopy robotics, there are still several problems that need a solution. These problems basically concern robotic locomotion and instrument control, as well as clinical application. In most cases, the technology is still under development. The current fields of investigation are augmented reality, advances in actuation and reduction of hysteresis, optical analysis, wireless movement transmission and many others. Besides endoscopic submucosal dissection, other promising fields of implementation of endoscopy robots are natural orifices transluminal endoscopic surgery and bariatric endoscopy. Obviously, endoscopy robots are expensive, but both doctors and health system providers are becoming more aware of the possibilities that these platforms can offer. Improvement of the performance of endoscopy robots undoubtedly will lead to their widespread use and, therefore, a balance in cost-effectiveness.

Facilitating endoscopic submucosal dissection: double balloon endolumenal platform significantly improves dissection time compared with conventional technique (with video)

BACKGROUND

Flexible endoscopes ability to manipulate the intestinal environment is limited. As a result, complex endolumenal procedures are often technically demanding and result in long procedure times, impacting institutional resources. Single- and double-balloon add-on endoscopic devices have been employed throughout the GI tract to facilitate tissue control e.g., small bowel enteroscopy, with recent reports suggesting a possible colonic utility for complex procedures e.g., ESD. Our objective was to objectively analyze the efficacy of a new double-balloon device in performing ESD.

METHODS

Ex vivo-12 simulated colonic lesions were created in porcine rectum using a standard 40 mm diameter template. Two categories were evaluated, standard cap technique ESD and double-balloon assisted ESD with retraction (ESD-R). Cases were performed sequentially. In vivo-Six, 40 mm lesion ESD-R's were performed in a porcine model. The primary outcomes of this study were total procedure and dissection times.

RESULTS

In ex vivo studies, the median total procedure time with the double-balloon platform was significantly shorter than the traditional ESD technique (29 ± 18 vs. 57 ± 21 min, p = 0.03). In the in vivo studies, lesions were successfully removed in a mean time of 48 min, with a dissection time of 20 min with no significant complications. Balloon-clip retraction and specimen retrieval capabilities were used in all double-balloon assisted cases. After 6 cases, times were significantly shorter (ex vivo 47 vs. 17 min; in vivo 57 vs. 27 min).

CONCLUSIONS

We have demonstrated the development of a unique technical ESD method facilitated by a new double-balloon device. Ex and in vivo investigation demonstrated superiority of ESD-R over the conventional ex vivo method. The DB device provided increased stability, improved visualization and tissue traction, which significantly reduced dissection time. Such an approach may increase safety, improve patient outcomes, and may prevent unnecessary surgeries for benign conditions.

Polypoid nodule scar after gastric endoscopic submucosal dissection: results from a multicenter study

Background and study aims  A post-endoscopic submucosal dissection (ESD) scar is expected to look homogeneous, however, some patients develop benign polypoid nodule scar (PNS). Incidence of PNS is unknown, yet these scars have direct clinical implications because they may render evaluation of post-ESD neoplastic recurrence difficult. Therefore, we reviewed the clinical experience of 5 ESD referral centers and evaluated their PNS incidence and clinical management. Patients and methods  This was a retrospective multicenter case series enrolling patients that underwent R0, curative gastric ESD from 2003 to 2015 in 5 academic centers. PNS was defined as ESD site nodularity with hyperplastic or regenerative tissue histology. Results  A total of 2275 patients underwent gastric ESD with endoscopy control and 28 patients (18 men/10 women) developed PNS for overall incidence of 1.2 %. Incidence of PNS ranged from 0.15 % to 11.4 % between centers. All patients that developed PNS had primary neoplastic lesions located in the distal stomach. Considering only lesions situated in the antrum (n = 912), incidence of PNS was 3.1 %. After mean follow-up of 43 months (range 6 - 192), no malignant recurrence in the PNS has been identified. In five patients (17.8 %) PNS disappeared after a mean of 18 months. Conclusion  PNS occurs exclusively after ESD in the distal stomach in approximately 3.1 % of patients. Although PNS appearance can be concerning, no malignant recurrence was observed after curative R0 resection. Therefore, PNS should be viewed as a benign alteration that does not require any type of intervention, other than endoscopic surveillance.

Short-term outcomes of endoscopic submucosal dissection versus laparoscopic surgery for colorectal neoplasms: An observational study

OBJECTIVES

With endoscopic submucosal dissection and laparoscopic surgery, treatment for colorectal neoplasms has become minimally invasive. However, few studies have compared endoscopic submucosal dissection with laparoscopic surgery for colorectal neoplasms, excluding deeply invasive cancer on preoperative diagnosis.

METHODS

We retrospectively reviewed the files of patients who had undergone endoscopic submucosal dissection or laparoscopic surgery for colorectal neoplasms between November 2005 and December 2015. We limited patients who were not suspected preoperatively to have aggressive submucosal invasion >1,000 μm.

RESULTS

Ninety-five patients underwent endoscopic submucosal dissection and 37 underwent laparoscopic surgery. Cases of endoscopic submucosal dissection tended to involve rectal neoplasms more often than colonic neoplasms, shorter operative times, and shorter lengths of hospital stay compared with laparoscopic surgery. The perforation rate during colonic endoscopic submucosal dissection in the early period (November 2005 to December 2010) and late period (January 2011 to December 2015) was 14.8% and 2.9%, respectively. In all cases of perforation during colonic endoscopic submucosal dissection, the ability to maneuver the endoscope was compromised. Though tumors were larger in patients who underwent rectal endoscopic submucosal dissection compared with colonic endoscopic submucosal dissection, the perforation and postoperative bleeding rates with rectal endoscopic submucosal dissection were both 3.2%. The most common indication for laparoscopic surgery was difficulty performing endoscopic submucosal dissection. Serious complications were rare.

CONCLUSIONS

For colonic neoplasms, laparoscopic surgery should be considered when endoscopic submucosal dissection is technically difficult in the early period. For rectal neoplasms, endoscopic submucosal dissection is desirable even for those of large size.

Effect of the midazolam added with propofol-based sedation in esophagogastroduodenoscopy: A randomized trial

BACKGROUND AND AIM

Although propofol has been widely used for sedation during esophagogastroduodenoscopy (EGD), adverse events including hypoxia and hypotension may be a concern in the propofol-based sedation. We aimed to analyze whether administration of midazolam would improve safety and efficacy of propofol-based sedation in EGD.

METHODS

One hundred twenty patients who were scheduled to undergo diagnostic EGD were randomly assigned to either midazolam plus propofol (MP) or propofol alone groups. In the MP group, 2 mg of midazolam and 10 mg of propofol were given initially. In the propofol alone group, 40-60 mg of propofol was given initially. In both groups, 20 mg of propofol was given repeatedly to maintain moderate sedation as needed. Vital signs including oxygen saturation were monitored every 2 min. After the patients fully recovered, satisfaction score was investigated from endoscopists, nurses, and patients, respectively.

RESULTS

The baseline characteristics did not differ between the MP and propofol alone groups. The mean required doses of propofol was (mean ± standard deviation) 0.3 ± 0.3 and 0.8 ± 0.2 mg/kg in the MP and propofol alone groups, respectively (P < 0.001). In addition, sedation-related adverse events and recovery time did not differ between the two groups. The proportion of satisfactory did not differ between the two groups (MP vs propofol alone; proportion; patient, 95.0% vs 93.3%, P > 0.999; endoscopist, 73.3% vs 80.0%, P = 0.064; nurse, 73.3% vs 76.7%, P = 0.551).

CONCLUSION

Adding midazolam to propofol did not reduced the safety and efficacy, and sedation using propofol alone could be suitable for sedation during diagnostic EGD.

Early esophageal squamous cell carcinoma management through endoscopic submucosal dissection

The incidence of esophageal cancer is steadily increasing worldwide. Outcome is poor, given that the majority of cases are diagnosed at advanced disease stages. However, when detected at early stages, esophageal tumors can be curatively treated through less invasive methods, resulting in a 5-year survival rate above 90%. Therefore, it is essential to identify the high-risk population and recommend those patients undergo screening using high-resolution endoscopy, adding the resources of chromoendoscopy with Lugol's solution (or digital chromoendoscopy) and magnification. Such systematized examination makes it possible to recognize early-stage esophageal neoplasia and propose endoscopic submucosal dissection as treatment. In that procedure, the tumor is resected en bloc, resulting in lower morbidity and mortality, compared with previous standard treatment, including early-stage esophagectomy. The present article is a review of the latest advances in the management of superficial esophageal tumors through endoscopic submucosal dissection.

Management of complex polyps of the colon and rectum

PUPRPOSE

Benign polyps that are technically challenging and unsafe to remove via polypectomy are known as complex polyps. Concerns regarding safety and completeness of resection dictate they undergo advanced endoscopic techniques, such as endoscopic mucosal resection or surgery. We provide a comprehensive overview of complex polyps and current treatment options.

METHODS

A review of the English literature was conducted to identifyarticles describing the management of complex polyps of the colon and rectum.

RESULTS

Endoscopic mucosal resection is the standard of care for the majority of complex polyps. Only polyps that fail endoscopic mucosal resection or are highly suspicious of invasive cancer but which cannot be removed endoscopically warrant surgery.

CONCLUSION

Several factors influence the treatment of a complex polyp; therefore, there cannot be a "one-size-fitsall" approach. Treatment should be tailored to the lesion's characteristics, the risk of adverse events, and the resources available to the treating physician.

Learning colorectal endoscopic submucosal dissection: a prospective learning curve study using a novel ex vivo simulator

BACKGROUND

Endoscopic submucosal dissection (ESD) is increasingly being used in Asia as a minimally invasive therapy to eradicate large laterally spreading superficial tumors in the colon. To date, the learning curve and effectiveness of ex vivo simulators in colonic ESD training remain unclear. The aim of the study is to determine the learning curve of colonic ESD in an ex vivo simulator.

METHODS

We conducted a prospective study of colon ESD in ex vivo porcine colons in a prototype simulator. Three endoscopists with prior experience in gastric ESD but with no experience in colonic ESD each performed 30 ESD resections on standardized lesions in the rectosigmoid and left colon of the porcine simulator. Procedure time, en bloc resection status, and perforation were recorded.

RESULTS

All 90 lesions were resected using the ESD technique. The mean time of procedure was 49.6 min (standard deviation 29.6 min). The aggregate rate of perforation was 14.4% and the aggregate rate of non-en bloc resection was 5.6%. Using a composite quality score integrating complications and procedural time, it was found that there was a significant difference between two local polynomial regression lines when using a cut-point at the 9th procedure (p = 0.04), reflecting the point at which most of the learning curve is traversed.

CONCLUSIONS

In this study, there were significant improvements realized in colonic ESD performance after 9 colon ESD procedures in ex vivo specimens. Although training will depend on endoscopist skill and expertise, we suggest at least 9 ex vivo procedures prior to moving to live animal or proctored training in colonic ESD.

Gastroenterological surgery in Japan: The past, the present and the future

In the last two centuries, there has been remarkable progress in the field of gastroenterological surgery, including the curative resection of cancers, replacement of failed organs through transplantation, increased safety of undergoing major surgeries and decreased operative morbidity through developments in minimal access surgery. Japan has very much been at the forefront of these advances, as is evident from the present review, from advancing the surgical management of gastric cancer to the pioneering work in live-donor transplantation. This review also highlights many instances where surgical management of the same pathologies has evolved differently between Japan and the West. It is encouraging that many procedures established in Japan are eventually taken up by the West, often after rigorous assessment affirming the quality and applicability of such techniques. In Japan, many of the crucial issues in gastroenterological surgery are increasingly addressed through large multi-institutional prospective control trials, ensuring that Japanese surgeons continue to contribute to the advances in gastroenterological surgery.

Clinical relevance of aberrant polypoid nodule scar after endoscopic submucosal dissection

AIM

To describe a series of patients with aberrant polypoid nodule scar developed after gastric endoscopic submucosal dissection (ESD), and to discuss its pathogenesis and clinical management.

METHODS

We reviewed retrospectively the endoscopic database of two academic institutions located in Brazil and Japan and searched for all patients that underwent ESD to manage gastric neoplasms from 2003 to 2015. The criteria for admission in the study were: (1) successful en bloc ESD procedure with R0 and curative resection confirmed histologically; (2) postoperative endoscopic examination with identification of a polypoid nodule scar (PNS) at ESD scar; (3) biopsies of the PNS with hyperplastic or regenerative tissue, reviewed by two independent experienced gastrointestinal pathologists, one from each Institution. Data were examined for patient demographics, Helicobacter pylori status, precise neoplastic lesion location in the stomach, tumor size, histopathological assessment of the ESD specimen, and postoperative information including medical management, endoscopic and histological findings, and clinical outcome.

RESULTS

A total of 14 patients (10 men/4 women) fulfilled the inclusion criteria and were enrolled in this study. One center contributed with 8 cases out of 60 patients (13.3%) from 2008 to 2015. The second center contributed with 6 cases (1.7%) out of 343 patients from 2003 to 2015. Postoperative endoscopic follow-up revealed similar findings in all patients: A protruded polypoid appearing nodule situated in the center of the ESD scar surrounded by convergence of folds. Biopsies samples were taken from PNS, and histological assessment revealed in all cases regenerative and hyperplastic tissue, without recurrent tumor or dysplasia. Primary neoplastic lesions were located in the antrum in 13 patients and in the angle in one patient. PNS did not develop in any patient after ESD undertaken for tumors located in the corpus, fundus or cardia. All patients have been followed systematically on an annual basis and no malignant recurrence in the ESD scar has been identified (mean follow-up period: 45 mo).

CONCLUSION

PNS may occur after ESD for antral lesions and endoscopically look concerning, especially for the patient or the family doctor. However, as long as curative R0 resection was successfully achieved and histology demonstrates only regenerative and hyperplastic tissue, PNS should be viewed as a benign alteration that does not require any type of intervention, other than endoscopic surveillance.

Diagnosis of a submucosal mass at the staple line after sigmoid colon cancer resection by endoscopic cutting-mucosa biopsy

A 48-year-old man underwent laparoscopic sigmoid colon resection for cancer and surveillance colonoscopy was performed annually thereafter. Five years after the resection, a submucosal mass was found at the anastomotic staple line, 15 cm from the anal verge. Computed tomography scan and endoscopic ultrasound were not consistent with tumor recurrence. Endoscopic mucosa biopsy was performed to obtain a definitive diagnosis. Mucosal incision over the lesion with the cutting needle knife technique revealed a creamy white material, which was completely removed. Histologic examination showed fibrotic tissue without caseous necrosis or tumor cells. No bacteria, including mycobacterium, were found on culture. The patient remains free of recurrence at five years since the resection. Endoscopic biopsy with a cutting mucosal incision is an important technique for evaluation of submucosal lesions after rectal resection.

What is the best therapeutic strategy for colonoscopy of colorectal neoplasia? Future perspectives from the East

Development and improvement of endoscopic techniques and devices have changed the treatment of colorectal tumors over the last decade. For the treatment of diminutive polyps, the cold snare technique of the West is becoming a promising treatment in the East because of its short procedure time and low rate of delayed bleeding by eliminating the delayed effect of electrocautery. Rather than using piecemeal endoscopic mucosal resection or surgical resection for the treatment of large superficial tumors, the technique of the East of endoscopic submucosal dissection (ESD) achieves a high success rate of en bloc R0 resection, enabling detailed pathological evaluation with less invasive treatment. This procedure should also be useful in the West where large colorectal tumors are more frequent than in the East. Regarding outcomes, however, in the literature, the definition of 'curative resection' remains somewhat inconsistent and long-term outcomes of patients with deep submucosal and/or lymphovascular invasion in the en bloc specimen have not yet been determined. Large prospective, as well as retrospective, studies of these patients are warranted. When colorectal ESD is difficult because of size or location, the pocket-creation method and/or double-balloon-assisted technique may be useful. In the East, high-quality magnified chromoendoscopy is widely available, and endoscopists try to identify focal submucosal invasion. In the West, a systematic evaluation of surveillance for the prevention of colorectal cancer has been done and is highly refined. The East and West have much to learn from each other.

Application of robotics in gastrointestinal endoscopy: A review

Multiple robotic flexible endoscope platforms have been developed based on cross specialty collaboration between engineers and medical doctors. However, significant number of these platforms have been developed for the natural orifice transluminal endoscopic surgery paradigm. Increasing amount of evidence suggest the focus of development should be placed on advanced endolumenal procedures such as endoscopic submucosal dissection instead. A thorough literature analysis was performed to assess the current status of robotic flexible endoscopic platforms designed for advanced endolumenal procedures. Current efforts are mainly focused on robotic locomotion and robotic instrument control. In the future, advances in actuation and servoing technology, optical analysis, augmented reality and wireless power transmission technology will no doubt further advance the field of robotic endoscopy. Globally, health systems have become increasingly budget conscious; widespread acceptance of robotic endoscopy will depend on careful design to ensure its delivery of a cost effective service.

Assessing the stability and safety of procedure during endoscopic submucosal dissection according to sedation methods: a randomized trial

BACKGROUND

Although endoscopic submucosal dissection (ESD) is routinely performed under sedation, the difference in ESD performance according to sedation method is not well known. This study attempted to prospectively assess and compare the satisfaction of the endoscopists and patient stability during ESD between two sedation methods.

METHODS

One hundred and fifty-four adult patients scheduled for ESD were sedated by either the IMIE (intermittent midazolam/propofol injection by endoscopist) or CPIA (continuous propofol infusion by anesthesiologist) method. The primary endpoint of this study was to compare the level of satisfaction of the endoscopists between the two groups. The secondary endpoints included level of satisfaction of the patients, patient's pain scores, events interfering with the procedure, incidence of unintended deep sedation, hemodynamic and respiratory events, and ESD outcomes and complications.

RESULTS

Level of satisfaction of the endoscopists was significantly higher in the CPIA Group compared to the IMIE group (IMIE vs. CPIA; high satisfaction score; 63.2% vs. 87.2%, P=0.001). The incidence of unintended deep sedation was significantly higher in the IMIE Group compared to the CPIA Group (IMIE vs. CPIA; 17.1% vs. 5.1%, P=0.018) as well as the number of patients showing spontaneous movement or those requiring physical restraint (IMIE vs. CPIA; spontaneous movement; 60.5% vs. 42.3%, P=0.024, physical restraint; 27.6% vs. 10.3%, P=0.006, respectively). In contrast, level of satisfaction of the patients were found to be significantly higher in the IMIE Group (IMIE vs. CPIA; high satisfaction score; 85.5% vs. 67.9%, P=0.027). Pain scores of the patients, hemodynamic and respiratory events, and ESD outcomes and complications were not different between the two groups.

CONCLUSION

Continuous propofol and remifentanil infusion by an anesthesiologist during ESD can increase the satisfaction levels of the endoscopists by providing a more stable state of sedation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01806753.

Endoscopic submucosal dissection in gastric lesions: the 100 cases experience from a tertiary reference center in West

OBJECTIVE

Endoscopic submucosal dissection (ESD) is an endoscopic treatment method widely used in premalignant and malignant lesions in countries of the Far East. This method, which is difficult technically and has a high complication risk rate, has rarely been performed in the West, because of the fewer number of upper gastrointestinal lesions. In the present study, we aimed to present our results of gastric ESD procedures in respect to the learning curve.

METHODS

A total of 100 ESD procedures, which were performed in the stomach between April 2012 and September 2014, were recorded prospectively before and after the procedure. Patient data were analyzed retrospectively. ESD procedures were numbered chronologically; the first 30 patients constituted group 1, whereas the rest were classified as the group 2. ESD results were compared between the groups.

RESULTS

In a total of 95 patients, 100 gastric ESDs were performed. The overall en-bloc and complete resection rates were 93% and 92%, respectively. In respect of the learning curve, there were significant differences in the sizes of lesions and tissues obtained, procedure duration and dissection rate, snare use and knife preferences between groups (p = 0.002, p < 0.001, p = 0.003, p < 0.001, p = 0.009, and p < 0.001, respectively). No significant difference was detected in the en-bloc and complete resection rates and complications between the groups.

CONCLUSION

According to guideline recommendations and masters for ESD, if ESD training is initiated and continued, successful ESD may be performed in localized lesions in the stomach.

A single-center experience of endoscopic submucosal dissection performed in a Western setting

BACKGROUND

Compared with the piecemeal resection associated with endoscopic mucosal resection, endoscopic submucosal dissection (ESD) enables en bloc resection of larger lesions, allows for more accurate histological assessments, and has reduced recurrence rates. ESD is not widely performed in Western countries given increased technical difficulty, high complication rates, and long procedure times.

AIMS

To evaluate the safety and efficacy of ESD in a single center in the USA.

METHODS

A retrospective study on a prospectively collected database identified cases in which a single operator (IW) performed ESD at a tertiary referral center. Twenty cases were identified, nine in the upper digestive tract (four esophagus and five stomach) and 11 in the lower digestive tract (nine rectal and two sigmoid colon). Data regarding lesion location, pathology, method of ESD (composition/volume of lifting injection and resection method), post-procedure complications, and margin involvement were collected.

RESULTS

En bloc resection was obtained in 14/20 patients (70 %). The average procedure time was 202 min in the esophagus, 148 min in the stomach, and 106 min for lower lesions. A major complication (perforation) occurred in 1/20 cases (5 %). Complete resection was obtained in 14/20 (70 %). R0 resection was obtained in 16/20 (80 %) cases.

CONCLUSIONS

The complication, en bloc resection, and complete resection rates of this study are similar to those found in large studies on ESD performed in Eastern settings. ESD is safe and efficacious for en bloc resections of pre-malignant and early-invasive lesions, and should be offered to patients with suitable lesions in Western settings.

The usage of overtube has a favorable effect on endoscopic submucosal dissection

BACKGROUND

Endoscopic submucosal dissection (ESD) may be very time consuming, and depending on the anesthesia, the contents of the stomach may reflux to the esophagus and cause the patient to aspirate. To prevent these situations, many practitioners suggest using an overtube, but no study has been done to evaluate the effect of the use of an overtube while performing the ESD procedure. Our aim was to investigate the effects of performing an upper gastrointestinal ESD with and without overtube.

METHODS

Records of patients who underwent ESD were evaluated for histopathological results, complications, speed of dissection, dosages of anesthetic medications, and number of suctions performed during the procedure. The patients were classified into two depending on whether an overtube was used or not.

RESULTS

There were a total of 58 patients on which 63 upper gastrointestinal ESD procedures were performed. Regarding age, gender, localization of the lesions, duration of the procedures, dosage of propofol, histopathological results, rate of complete resection, and rate of en-bloc resection, there was no difference between the two groups (p > 0,05). But the size of the lesions, the size of the resected specimen, and the speed of dissection were statistically different in two groups (p = 0.018, p < 0.001, p < 0.001, respectively).The need for suction during the procedure was much lower in the overtube group than those with no overtube (p < 0.001).

CONCLUSIONS

We conclude that using an overtube during an upper gastrointestinal ESD decreases the need for suction, favors the speed of dissection, and eases the comfort of the procedure.

Endoluminal resection and tissue acquisition

Endoscopic resection as curative treatment is feasible and indicated for gastrointestinal adenomas and early cancer limited to the mucosal layer and submucosal layers, where the risk for nodal and distant metastases is minimal. The initial technique of endoscopic resection, endoscopic mucosal resection, was limited by the inability to have en bloc resections for lesions larger than 2 cm. This meant that proper assessment of resection margins and depths was not possible in these cases, with the risk of incomplete resection and remnant lesions. In the last decade, the technique of endoscopic submucosal dissection was introduced, and this has allowed en bloc resection of superficial cancers of the esophagus, stomach, and colon. Cumulative data have shown high en bloc resection rates and excellent short-term and long-term outcomes when treatment inclusion criteria are adhered to. Endoscopic resection techniques were recently applied in the context of submucosal lesions. In the case of lesions located in the muscularis mucosa and submucosal layers, the gastrointestinal wall is not breached during endoscopic resection. However, in the case of submucosal lesion located in the muscularis propria layer, endoscopic mucosal resection or endoscopic submucosal dissection would result in perforation which may not be easily closed endoscopically. The technique of endoscopic submucosal tunneling was introduced in the context of peroral endoscopic myotomy for the treatment of achalasia. The principle was extended to the resection of tumors arising from the muscularis propria layer, with promising results.

Efficacy and safety of proton pump inhibitors (PPIs) plus rebamipide for endoscopic submucosal dissection-induced ulcers: a meta-analysis

OBJECTIVE

To compare the efficacy of proton pump inhibitors (PPIs) with rebamipide versus PPIs alone for the treatment of ulcers after endoscopic submucosal dissection (ESD).

METHODS

PubMed, Web of Science, Medline, Embase, the Cochrane Central Register of Controlled Trials and China Naitonal Knowledge Infrastructure were searched up to the end of October 2013 in order to identify all randomized controlled trials reporting the effects of PPIs plus rebamipide on healing ulcers after ESD. The outcome measurement was complete ulcer healing.

RESULTS

A total of six studies involving 724 patients were included. The pooled data suggested a significantly higher rate of ulcer healing after endoscopic therapy among patients treated with PPIs plus rebamipide than among those treated with PPIs alone [odds ratio (OR)=2.40, 95% confidence interval (CI): 1.68-3.44]. The subgroup analysis showed PPI plus rebamipide therapy to be more effective in healing ESD-induced ulcers than treatment with PPIs alone after both four (OR=2.22, 95%CI: 1.53-3.24) and eight weeks of treatment (OR=3.19, 95%CI: 1.22-8.31). In addition, the combination therapy was found to be significantly more effective than the use of PPIs alone for all ESD ulcers greater than 20 mm in size (OR=4.77, 95%CI: 2.22-10.26). There were no significant differences between the treatment groups with regard to ulcer location (low, middle or upper stomach) or the presence of absence of H. pylori infection. No serious adverse events were observed in either group.

CONCLUSION

The results of this meta-analysis suggest that treatment with PPIs plus rebamipide is superior to PPI monotherapy for healing ESD-induced ulcers over four weeks, particularly large ulcers. However, more well-designed trials are needed to confirm these findings.