Clinical outcomes of per-oral endoscopic tumor resection for submucosal tumors in the esophagus and gastric cardia

The efficacy and safety of submucosal tunneling endoscopic resection in treating large esophageal subepithelial lesions

BACKGROUND

Submucosal tunneling endoscopic resection (STER) is considered an effective, safe and minimally invasive treatment for esophageal subepithelial lesions (SELs) with maximal dilameter less than 3.0 cm, yet its efficacy for lesions over 3.0 cm remains unclear. This study aimed to evaluate the application value of STER for SELs of varying sizes.

METHODS

Consecutive patients with esophageal SELs who underwent STER were retrospectively enrolled from May 2017 to March 2024. Baseline characteristics, surgical information and prognosis were collected and compared among patients with SELs of different sizes, as defined by the maximal diameter of the postoperative specimen.

RESULTS

A total of 133 patients were included, among whom 69 with SELs < 3.0 cm, 31 with SELs between 3.0 and 5.0 cm, 33 with SELs ≥ 5.0 cm. 1 case with SELs ≥ 5.0 cm was converted to endoscopic submucosal dissection (ESD) due to the tumor's adhesion to the epithelial layer. Among those who completed the STER procedure, the en bloc resection rate was 100.0% for all three subgroups, and the recurrence and metastasis rates were 0.0%, demonstrating that STER is effective for SELs of all sizes. However, SELs ≥ 5.0 cm were associated with more adverse events, a higher number of difficult procedures, and more frequent intensive care unit (ICU) transfers (all p < 0.050).

CONCLUSIONS

STER is effective and safe for treating esophageal SELs. For lesions exceeding 5 cm, while still feasible, the procedure requires meticulous planning, advanced techniques and careful monitoring due to increased complexity and risks.

Clinical characteristics and esophageal motility in patients with gastric cardia submucosal tumors and associated changes after endoscopic resection

BACKGROUND

This study aimed to investigate the clinical characteristics and esophageal motility of patients with gastric cardia submucosal tumors (SMTs) and the associated changes after endoscopic resection based on high-resolution impedance manometry (HRIM).

METHODS

From our electronic database, we identified patients who underwent pre-operative evaluation of gastric cardia SMTs between 2015 and 2023. All patients completed standardized symptom questionnaires and underwent endoscopic ultrasonography and HRIM. Endoscopic resection via submucosal dissection or submucosal tunnel endoscopic resection was performed, followed by esophagogastroduodenoscopy and HRIM three months later. Esophageal motility on HRIM was compared based on the updated Chicago Classification v4.0.

RESULTS

Thirty patients (mean age, 47.4 ± 12.8 years; male, 50%) were analyzed. Most patients were asymptomatic (43.3%), while others presented with epigastralgia, regurgitation, chest pain, or dysphagia. On endoscopic ultrasonography, the average tumor size was 16.7 ± 4.5 mm (range, 10.0-30.0 mm), and most tumors originated from the fourth layer (80%). On HRIM, eight patients (26.7%) had abnormal esophageal motility, including five with ineffective esophageal motility (IEM) and three with esophagogastric junction outflow obstruction. Complete resection was achieved in 25 of the 27 patients (92.6%) who underwent endoscopic treatment. Pathology revealed leiomyomas (96%) and gastrointestinal stromal tumors (4%). No significant differences in symptom profiles or HRIM parameters were observed after tumor resection. Three patients with pre-operative IEM exhibited normal motility at the follow-up HRIM.

CONCLUSION

Up to 26.7% of patients with gastric cardia SMTs had abnormal esophageal motility on HRIM. Endoscopic resection of these SMTs was effective and safe and appeared to improve esophageal motility in patients with IEM.

Treatment strategy and clinical outcomes of thoracoscopic endoscopic cooperative surgery for submucosal tumors in the esophagus

PURPOSE

Recently, submucosal tumors (SMTs) of the esophagus have been treated with peroral endoscopic tumor resection (POET) and a new procedure called thoracoscopic endoscopic cooperative surgery (TECS). This study aimed to validate the treatment strategy for SMTs and determine whether or not TECS is a viable option when POET is not feasible.

METHODS

POET and TECS were performed in 12 patients between February 2020 and January 2024. The clinical characteristics and perioperative outcomes were retrospectively evaluated.

RESULTS

Six patients were included in each group, with most of the tumors located in the middle thoracic esophagus (75%). The general anesthesia duration was significantly longer in the TECS group than in the POET group (P < 0.001), but no significant differences in endoscopic procedure time, tumor mass index, oral intake date, or length of hospital stay were observed between the two groups. En bloc and R0 resections were performed in all patients. One patient in the TECS group experienced a Clavien-Dindo grade 3a adverse event, and no tumor recurrence occurred during the median follow-up period of 33 (range, 6-53) months.

CONCLUSION

TECS is a safe and feasible option for SMTs when POET is difficult to perform.

Clinicopathological features and treatment of gastrointestinal schwannomas

BACKGROUND

Gastrointestinal schwannomas (GIS) are rare neurogenic tumors arising from Schwann cells in the gastrointestinal tract. Studies on GIS are limited to small case reports or focus on specific tumor sites, underscoring the diagnostic and therapeutic challenges they pose.

AIM

To comprehensively examine the clinical features, pathological characteristics, treatment outcomes, associated comorbidities, and prognosis of GIS.

METHODS

The study population included patients diagnosed with GIS at the First Affiliated Hospital, Zhejiang University School of Medicine, between June 2007 and April 2024. Data were retrospectively collected and analyzed from medical records, including demographic characteristics, endoscopic and imaging findings, treatment modalities, pathological evaluations, and follow-up information.

RESULTS

In total, 229 patients with GIS were included, with a mean age of 56.00 years and a male-to-female ratio of 1:1.83. The mean tumor size was 2.75 cm, and most (76.9%) were located in the stomach. Additionally, 6.6% of the patients had other malignant tumors. Preoperative imaging and endoscopy frequently misdiagnosed GIS as gastrointestinal stromal tumors. However, accurate preoperative diagnosis was achieved using endoscopic ultrasound-guided fine-needle aspiration combined with immunohistochemical analysis, in which S100 and SOX-10 markers were mostly positive. Smaller tumors were typically managed with endoscopic resection, while larger lesions were treated with surgical resection. Follow-up results showed that most patients experienced favorable outcomes.

CONCLUSION

Preoperative diagnosis of GIS via clinical characteristics, endoscopy, and imaging examinations remains challenging but crucial. Endoscopic therapy provides a minimally invasive and effective option for patients.

Advances in Endoscopic Resection

This article provides an overview of recent advances in endoscopic resection techniques. It includes the brief overview of endoscopic submucosal dissection, regional differences in ESD indications, innovation of ESD techniques, and expansion to full-thickness resection. The article covers cold snare polypectomy for small polyps with tips, underwater endoscopic mucosal resection (U-EMR) for sessile lesions with tips and expanding role of U-EMR, and the key assistive techniques for ESD that have improved the safety and efficacy. Furthermore, it discusses the emerging field of endoscopic full-thickness resection including device-assisted and freehand exposure techniques.

Efficacy and safety of piecemeal submucosal tunneling endoscopic resection for giant esophageal leiomyoma

BACKGROUND AND AIMS

Giant esophageal leiomyoma usually requires a thoracotomy or thoracoscopic surgery, which is more invasive than an endoscopic treatment. The purpose of this study is to evaluate the efficacy and safety of piecemeal submucosal tunneling endoscopic resection (P-STER) for giant leiomyoma originating from the muscularis propria (MP) layer of the esophagus.

METHODS

This is a retrospective study. Patients with giant esophageal leiomyoma (transverse diameter ≥ 3 cm) who underwent P-STER were enrolled from November 2012 to May 2023. Clinical data and results were investigated.

RESULTS

A total of 16 patients were enrolled for analysis. The lesion mean transverse diameter and longitudinal diameter were 4.22 ± 1.20 cm and 6.20 ± 1.57 cm, respectively. Our mean operation time was 195.38 ± 84.99 min. The mean number of piecemeal resected was 4.31 ± 2.36. An adverse event noted was an esophageal fistula that occurred in one case (6.25%) and was treated conservatively. The mean length of hospital stay was around 11.81 ± 7.30 days. The mean total hospitalization cost was U.S. dollars (USD) $5976.50 ± 2866.39. No recurrence or metastasis was found during the follow-up period.

CONCLUSIONS

P-STER can be an effective and safe treatment for giant leiomyoma originating from the MP layer of the esophagus.

Efficacy and histologic frequencies of endoscopic ultrasonography-guided tissue acquisition using conventional fine-needle aspiration needles for gastric subepithelial hypoechoic mass

Introduction/Purpose

For gastric subepithelial lesions (GSELs) showing a hypoechoic mass (HM) on endoscopic ultrasonography (EUS) imaging, the utility of EUS-guided tissue acquisition using conventional fine-needle aspiration needles (EUS-TA-CFNAN) and the frequency of histological types remain unclear. This study aimed to examine this issue.

Methods

This prospective observational study enrolled 291 consecutive patients who underwent EUS-TA-CFNAN for GSELs showing an HM (GSELHM) on EUS imaging. Immunohistochemical analysis was performed for all EUS-TA-CFNAN and surgically resected specimens. The main outcome measures were the technical results of EUS-TA-CFNAN and the frequency of histological types in GSELHM.

Results

The endoscopic ultrasound-guided tissue acquisition using conventional fine-needle aspiration needle diagnosis rate for GSELHM was 80.1% (95% confidence interval [CI]: 75.0-84.5, 233/291). It was significantly lower for antrum (P = 0.004) and lesions smaller than 2 cm (P = 0.003). There were no adverse events. The immunohistochemical diagnoses of EUS-TA-CFNAN included 149 cases of gastrointestinal stromal tumour (GIST) (51.2%), 48 cases of leiomyoma (16.5%), 11 cases of schwannoma (3.8%), 8 cases of the ectopic pancreas (2.7%), 5 cases of subepithelial lesion like cancer (1.7%), 12 cases of other lesions (4.1%), and 58 cases of undiagnosable lesions (19.9%). The frequency of malignant or potentially malignant tumour in GSELHM was 55.0% (95% CI: 49.1-60.8, 160/291). Surgery was performed in 149 patients according to the conclusive EUS-TA-CFNAN results, in which the diagnostic accuracy of EUS-TA-CFNAN was 97.3% (95% CI: 94.7-99.9, 145/149).

Conclusion

The use of EUS-TA-CFNAN for GSELHMs is safe and accurate. Gastric subepithelial lesions showing a hypoechoic mass have a reasonably high possibility of containing malignant or potentially malignant tumours, including GISTs.

AGA Clinical Practice Update on Endoscopic Full-Thickness Resection for the Management of Gastrointestinal Subepithelial Lesions: Commentary

DESCRIPTION

Subepithelial lesions of the gastrointestinal tract are not encountered uncommonly during routine endoscopy. There has been remarkable progress in the development of endoscopic options for the resection of subepithelial lesions, including full-thickness resection. The purpose of this American Gastroenterological Association (AGA) Clinical Practice Update (CPU) is to describe the various techniques for endoscopic full-thickness resection and to facilitate their appropriate application in the management of subepithelial lesions.

METHODS

This CPU was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology.

Effective submucosal tunneling endoscopic resection (STER) of a giant esophageal leiomyoma

We report the successful removal of a giant esophageal leiomyoma using submucosal tunneling endoscopic resection in a 37-year-old woman with significant dysphagia.

The Journey from Endoscopic Submucosal Dissection to Third Space Endoscopy

With the advent of endoscopic submucosal dissection, a variety of endoscopic devices including knives and high-frequency electrosurgical unit have become available. In addition, the concept of natural orifice transluminal endoscopic surgery pushed flexible endoscopic surgery ahead. In this review, the birth of peroral endoscopic myotomy and its expansion into the field of submucosal endoscopy are reviewed.

A Look into the Future of Endoscopic Submucosal Dissection and Third Space Endoscopy: The Role for Robotics and Other Innovation

Endoscopic resection has been widely applied especially in endoscopic submucosal dissection and third space endoscopy (TSE). Flexible endoluminal robotics allow performance of endoscopic submucosal dissection with exposure of the submucosal plane for precise dissection using two robotic arms. The introduction of TSE revolutionized the horizon of therapeutic endoscopy to the submucosal space beneath and beyond the mucosa. Advantages of TSE include avoidance of full thickness incision in gastrointestinal tract through the submucosal tunneling for performance of peroral endoscopic myotomy and submucosal tunneling endoscopic resection. In future, robotic-driven devices should be developed to enhance performance of complex endoluminal procedures and TSE.

Submucosal endoscopy: the present and future

Submucosal endoscopy or third-space endoscopy utilizes the potential space between the mucosal and muscularis layers of the gastrointestinal tract to execute therapeutic interventions for various diseases. Over the last decade, endoscopic access to the submucosal space has revolutionized the field of therapeutic endoscopy. Submucosal endoscopy was originally used to perform endoscopic myotomy in patients with achalasia cardia, and its use has grown exponentially since. Currently, submucosal endoscopy is widely used to resect subepithelial tumors and to manage refractory gastroparesis and Zenker's diverticulum. While the utility of submucosal endoscopy has stood the test of time in esophageal motility disorders and subepithelial tumors, its durability remains to be established in conditions such as Zenker's diverticulum and refractory gastroparesis. Other emerging indications for submucosal endoscopy include esophageal epiphrenic diverticulum, Hirschsprung's disease, and esophageal strictures not amenable to conventional endoscopic treatment. The potential of submucosal endoscopy to provide easy and safe access to the mediastinum and peritoneal spaces may open doors to novel indications and rejuvenate the interest of endoscopists in natural orifice transluminal endoscopic surgery in the future. This review focuses on the current spectrum, recent updates, and future direction of submucosal endoscopy in the gastrointestinal tract.

Evolving field of third-space endoscopy: Derivatives of peroral endoscopic myotomy

Third-space endoscopy, also known as submucosal endoscopy, allows for a wide range of therapeutic interventions within the submucosal layer and even into the muscular or subserosal layers of the gastrointestinal lumen. The technical development of peroral endoscopic myotomy (POEM) for achalasia has revolutionized the field of therapeutic endoscopy and the method has been continuously refined and modified. Although POEM has been applied to treat primary achalasia, it shows a favorable clinical response in other esophageal motility disorders and as a salvage treatment after previously failed intervention. Gastroesophageal reflux after POEM has drawn considerable attention and there have been major advancements in its prevention and management. POEM has led to advantageous derivatives such as peroral endoscopic tumor resection or submucosal tunneling endoscopic resection for resection of subepithelial lesions, Zenker POEM for hypopharyngeal diverticula, diverticular POEM for epiphrenic esophageal diverticula, and gastric POEM for refractory gastroparesis. These techniques have a similar concept, which constitutes submucosal tunneling with a mucosal flap valve and secure mucosal incision closure. The submucosal tunneling technique is widely accepted and continues to evolve. This study aimed to review in detail the indications, outcomes, and technical variations in POEM and explore several emerging submucosal tunneling procedures. This review will benefit future studies by providing a summary of recent developments in this field.

Updates in the Field of Submucosal Endoscopy

Submucosal endoscopy (third-space endoscopy) can be defined as an endoscopic procedure performed in the submucosal space. This procedure is novel and has been utilized for delivery to the submucosal space in a variety of gastrointestinal diseases, such as a tumor, achalasia, gastroparesis, and subepithelial tumors. The main submucosal endoscopy includes peroral endoscopic myotomy, gastric peroral endoscopic myotomy, Zenker peroral endoscopic myotomy, submucosal tunneling for endoscopic resection, and endoscopic submucosal tunnel dissection. Submucosal endoscopy has been used as a viable alternative to surgical techniques because it is minimally invasive in the treatment and diagnosis of gastrointestinal diseases and disorders. However, there is limited evidence to prove this. This article reviews the current applications and evidence regarding submucosal endoscopy while exploring the possible future clinical applications in this field. As our understanding of these procedures improves, the future of submucosal endoscopy could be promising in the fields of diagnostic and therapeutic endoscopy.

Landscape of esophageal submucosal tunneling endoscopic resection-related adverse events in a standardized lexicon: a large volume of 1701 cases

BACKGROUND

Submucosal tunneling endoscopic resection (STER) has been widely applied for esophageal submucosal tumors. This large volume study aims to provide a standard landscape of STER-related AEs for reference.

METHODS

1701 patients with esophageal SMTs undergoing STER were included at Zhongshan Hospital, Fudan University. Data of clinical characteristics and adverse events were collected and analyzed in depth. Adverse events were recorded by ASGE lexicon and graded by ASGE grading/Clavien-Dindo system. Risk factors for major AEs were analyzed by univariate and multivariate logistic regression.

RESULTS

Three hundred and twenty (18.8%) patients with 962 cases of adverse events were observed. Accordingly, 84 (5.0%) were classified as major AEs (moderate and severe) by ASGE grading and 37 (2.2%) were classified as major AEs (grades III-V) by Clavien-Dindo grading. First 1 year operation, distance > 6 cm from incision to tumor, piecemeal resection, partially extraluminal location, mucosal injury, and operation time > 60 min were included in the risk score model for major AEs of STER, with 57.1% sensitivity and 87.5% specificity.

CONCLUSIONS

STER was a safe procedure for diagnosis and treatment of esophageal SMTs with a total 18.8% incidence of AEs, among which only 5.0% were major AEs requiring therapeutic measurements.

Efficacy and Safety Analysis of Submucosal Tunnel Endoscopic Resection for Submucosal Masses in Esophageal Muscularis Propria

Objective

To analyze the efficacy and safety of submucosal tunnel endoscopic resection (STER) for the treatment of submucosal masses in esophageal muscularis propria.

Method

A total of 272 patients with submucosal masses in esophageal muscularis propria diagnosed and treated in our hospital from February 2019 to January 2022 were randomly selected for the study and then were randomly divided into the STER group (n = 136) and the endoscopic mucosal dissection (ESD) group (n = 136) according to the random number table method. Patients in the STER and ESD groups were treated with STER and ESD, respectively. The clinical data of patients from the two groups were collected and compared. The clinical effects and the changes of surgery-related indexes of patients after ESD and STER treatment were observed. The safety of ESD and STER was compared. The factors influencing the efficacy of STER treatment for submucosal masses in esophageal muscularis propria were analyzed.

Result

There were significant differences between the STER group and the ESD group in terms of tumor size, lesion level, adhesion and surgical approaches (P < 0.05). The effective rates of ESD treatment and STER treatment were 98.53% and 88.97%, respectively. Meanwhile, the effective rates of STER treatment were significantly higher than those in the control group (P < 0.05). In addition, the patients in the STER group had longer operation time, less blood loss, and shorter hospital stay compared with those in the ESD group (P < 0.05). Adverse reactions occurred during ESD treatment and STER treatment included delayed bleeding, adhesion, perforation, and pleural effusion with the total incidence of adverse reactions of 4.41% and 13.97%, respectively. The adverse reactions in STER group were prominently less than these in the ESD group (P < 0.05). Logistic multivariate regression analysis showed that independent risk factors, including tumor size, lesion level, adhesion, and surgical approaches, affected the efficacy of STER in the treatment of submucosal masses in esophageal muscularis propria (P < 0.05).

Conclusion

STER is an effective method for the treatment of submucosal masses in esophageal muscularis propria, which can exhibit a good effect with faster postoperative recovery and higher safety, thereby being worthy of clinical application and promotion. Tumor size, lesion level, adhesion, and surgical approaches are all related factors affecting the effect of STER treatment.

Successful endoscopic full-thickness resection of an exophytic subepithelial lesion with double scope traction technique

Video 1Video demonstrating the endoscopic full-thickness resection of an exophytic subepithelial lesion with "double scope traction" technique.

Endoscopic full‐thickness resection of an esophageal leiomyoma located in close proximity to the azygos vein

Third‐space endoscopic techniques, such as peroral endoscopic tumor resection (POET) and submucosal tunneling endoscopic resection (STER), enable access to deep organs and tissues that have been previously inaccessible with an endoscope. We present a 29‐year‐old man with a submucosal tumor (40 × 25 mm) located at 5 o'clock in the upper thoracic esophagus. Histological diagnosis by endoscopic ultrasound–fine needle aspiration was leiomyoma. Computed tomography showed the azygos vein posterior to the tumor. However, because endoscopic ultrasound revealed space between them, POET was performed. Because the tumor originated from the deep layer of the muscularis propria, full‐thickness resection was performed to achieve R0 resection. The azygos vein arch was seen through the mediastinal space after tumor enucleation. The final histopathological diagnosis was leiomyoma. POET is a potentially revolutionary endoscopic technique that enables full‐thickness resection of nonepithelial lesions. Preoperative computed tomography or endoscopic ultrasound to determine peritumoral anatomy is important to ensure safety. During the procedure, it is important to operate under direct vision, accurately identify the tumor boundary, and dissect along the boundary to avoid damaging the tumor and surrounding structures.

Therapeutic Endoscopy and the Esophagus: State of the Art and Future Directions

Therapeutic gastrointestinal endoscopy is rapidly evolving, and this evolution is quite apparent for esophageal diseases. Minimally invasive endoluminal therapy now allows outpatient treatment of many esophageal diseases that were traditionally managed surgically. In this review article, we explore the most exciting new developments. We discuss the use of peroral endoscopic myotomy for treatment of achalasia and other related diseases, as well as the modifications that have allowed its use in treatment of Zenker diverticulum. We cover endoscopic treatment of gastroesophageal reflux disease and Barrett's esophagus. Further, we explore advanced endoscopic resection techniques.

Per-oral Endoscopic Myotomy and Other Applications of Third Space Endoscopy: Current Status and Future Perspectives

INTRODUCTION

The modification of NOTES (natural orifice transluminal endoscopic surgery) by mucosal safety flap has introduced us to the world of third space endoscopy (TSE). POEM (per-oral endoscopic myotomy) for achalasia cardia being its first vista, the realm expanded so that we can now remove en bloc a subepithelial/intramural tumor by POET (per-oral endoscopic tumor resection), perform G-POEM (gastric per-oral endoscopic myotomy) for refractory gastroparesis, restore esophageal continuity in complete obstruction by performing POETRE (per-oral endoscopic tunneling for the restoration of the esophagus), divide the septum in Zenker diverticulum completely with negligible risk of perforation by Z-POEM (Zenker per-oral endoscopic myotomy) and relieve constipation in Hirschsprung disease by PREM (per-rectal endoscopic myotomy). However, the real potential of TSE became evident with the introduction of POEM with fundoplication. TSE has opened the gates of the peritoneal cavity. Improved expertise and equipment will make the role of endoscopist complimentary to the surgeon with the dawn of a new field in therapeutic endoscopy.

AREAS COVERED

This review intends to comprehensively discuss the various aspects of POEM for achalasia studied so far followed by a brief discussion about other applications of TSE and the future perspectives in this exciting field.

The Modern Age of POEM: the Past, Present and Future of Per-Oral Endoscopic Myotomy

BACKGROUND

Per-oral endoscopic myotomy (POEM) has gained widespread enthusiasm amongst foregut specialists since its introduction in the mid 2000s as an effective and less invasive treatment option for achalasia. As more than 6000 POEM procedures have been performed to date throughout the world, we aim to summarize the history and current state of POEM in the treatment of esophageal motility disorders.

METHODS

We performed a comprehensive review of the published literature focusing on the history and development of the POEM procedure, and its most current applications and outcomes.

RESULTS

Multiple favorable long-term studies have been published advocating for the use of POEM as a valid and perhaps the most valid treatment option for achalasia. The procedure is also increasingly being applied to a wider spectrum of esophageal motility disorders including type III achalasia, spastic esophageal disease or isolated lower esophageal sphincter (LES) dysfunction, as well as new endoluminal procedures such as submucosal tumor endoscopic resection (STER), endoscopic fundoplications (POEM-F) and peroral pyloromyotomy (POP or G-POEM).

CONCLUSIONS

While POEM is a proved and valid procedure, its further adoption is being threatened by external factors: challenges related to teaching, institutional support (politics) and insurance reimbursement. While this technique has come an incredible distance in its relatively short lifespan, the future of POEM in the USA will depend on the support from surgical societies to validate it as a valuable tool in the esophageal specialist's armamentarium, and to encourage a commitment to training in endoluminal surgery.

Innovative therapeutic endoscopy in the upper gastrointestinal tract: Review of Japan Gastroenterological Endoscopic Society Core Sessions

Workshops on "Innovative Therapeutic Endoscopy" for upper gastrointestinal tract diseases were held four times as the Japan Gastroenterological Endoscopic Society (JGES) Core Sessions at the 93rd to 96th Biannual Meetings of the JGES. A total of 48 research presentations (including two invited lectures) were reported, and various discussions were held on these topics. When the research presentations were categorized according to the therapeutic procedure, endoscopic submucosal dissection (ESD) was the most frequent with 28 presentations (58.3%), followed by laparoscopy endoscopy cooperative surgery (LECS) with six presentations (12.5%). When the research presentations were classified by the target organ of the therapeutic procedures, the duodenum was the most frequent with 26 presentations (54.1%), followed by the stomach with 13 presentations (27.1%). The most important issue was the establishment of a safe and reliable endoscopic resection method for duodenal lesions. Issues related to gastric ESD were establishing an efficient traction method and a method to prevent post-ESD bleeding in high-risk patients. Other important issues were establishment of an efficient traction method and methods of preventing delayed bleeding in high-risk patients who undergo gastric ESD, expansion of indications for minimally invasive treatment using LECS for gastric cancer, the development of endoscopic full-thickness resection (EFTR) for gastric submucosal tumors (SMTs), and improvement of per-oral endoscopic myotomy (POEM) for esophageal achalasia and per-oral endoscopic tumor resection (POET) for esophageal SMTs. Through the JGES Core Sessions, it is expected that the minimally invasive treatments using endoscopes developed in Japan will be further advanced.