Resection Of Submucosal Tumors Research Articles

Feasibility and safety of endoscopic full-thickness resection for submucosal tumors in the upper gastrointestinal tract, including predominantly extraluminal submucosal tumors (with video).

Endoscopic full-thickness resection (EFTR) for submucosal tumors (SMTs) has been technically challenging. This retrospective study aimed to evaluate the feasibility, safety, and efficacy of EFTR for upper gastrointestinal (GI) SMTs, including extraluminal lesions. We retrospectively investigated 232 patients with SMTs who underwent EFTR from January 2014 to August 2023. Clinicopathologic characteristics, procedure-related parameters, adverse events (AEs), and follow-up outcomes were assessed in all patients. The en-bloc resection and en-bloc with R0 resection rates were 98.7% and 96.1%, respectively. The average endoscopic tumor size measured 17.2 ± 8.7 mm, ranging from 6 to 50 mm. The resection time and suture time were 49.0 ± 19.4 min and 22.5 ± 11.6 min, respectively. In all, 39 lesions (16.8%) exhibited predominantly extraluminal growth. Gastrointestinal stromal tumors (GISTs) were the predominant pathology, accounting for 78.4% of the cases. Twenty-one patients (9.1%) encountered complications, including pneumothorax (1/232, 0.43%), hydrothorax (1/232, 0.43%), localized peritonitis (3/232, 1.29%), and fever (16/232, 6.9%). Although the incidence of postoperative fever was notably higher in the predominantly extraluminal group (7/39, 17.9%) compared to the predominantly intraluminal group (9/193, 4.7%, P = 0.008), there were no significant differences in outcomes of the EFTR procedure. No instances of recurrence were observed during the mean follow-up period of 3.7 ± 2.3 years. EFTR was found to be feasible, safe, and effective for resecting upper GI SMTs, including lesions with predominantly extraluminal growth. Further validation in a prospective study is warranted.

Predictors of difficult endoscopic resection of submucosal tumors originating from the muscularis propria layer at the esophagogastric junction.

BACKGROUNDEndoscopic resection approaches, including endoscopic submucosal dissection (ESD), submucosal tunneling endoscopic resection (STER) and endoscopic full-thickness resection (EFTR), have been widely used for the treatment of submucosal tumors (SMTs) located in the upper gastrointestinal tract. However, compared to SMTs located in the esophagus or stomach, endoscopic resection of SMTs from the esophagogastric junction (EGJ) is much more difficult because of the sharp angle and narrow lumen of the EGJ. SMTs originating from the muscularis propria (MP) in the EGJ, especially those that grow extraluminally and adhere closely to the serosa, make endoscopic resection even more difficult.AIMTo investigate the predictors of difficult endoscopic resection for SMTs from the MP layer at the EGJ.METHODSA total of 90 patients with SMTs from the MP layer at the EGJ were included in the present study. The difficulty of endoscopic resection was defined as a long procedure time, failure of en bloc resection and intraoperative bleeding. Clinicopathological, endoscopic and follow-up data were collected and analyzed. Statistical analysis of independent risks for piecemeal resection, long operative time, and intraoperative bleeding were assessed using univariate and multivariate analyses.RESULTSAccording to the location and growth pattern of the tumor, 44 patients underwent STER, 14 patients underwent EFTR, and the remaining 32 patients received a standard ESD procedure. The tumor size was 20.0 mm (range 5.0–100.0 mm). Fourty-seven out of 90 lesions (52.2%) were regularly shaped. The overall en bloc resection rate was 84.4%. The operation time was 43 min (range 16–126 min). The intraoperative bleeding rate was 18.9%. There were no adverse events that required therapeutic intervention during or after the procedures. The surgical approach had no significant correlation with en bloc resection, long operative time or intraoperative bleeding. Large tumor size (≥ 30 mm) and irregular tumor shape were independent predictors for piecemeal resection (OR: 7.346, P = 0.032 and OR: 18.004, P = 0.029, respectively), long operative time (≥ 60 min) (OR: 47.330, P = 0.000 and OR: 6.863, P = 0.034, respectively) and intraoperative bleeding (OR: 20.631, P = 0.002 and OR: 19.020, P = 0.021, respectively).CONCLUSIONEndoscopic resection is an effective treatment for SMTs in the MP layer at the EGJ. Tumors with large size and irregular shape were independent predictors for difficult endoscopic resection.

Reopenable clip over line method for the closure of full-thickness defect after gastric endoscopic full-thickness resection.

In recent years, the efficacy of endoscopic full-thickness resection for submucosal tumors has been reported [1] [2]. However, a reliable closure method for large full-thickness defects in the stomach remains unclarified. We developed the reopenable clip over line method for closing the mucosal defect after endoscopic submucosal dissection using reopenable clips and a line placed at the muscle layer and edge of the mucosal defect [3] [4] [5]. We report a new method of this type of closure of a 25-mm full-thickness defect in a porcine model ([Video 1]).

Invited Commentary: Submucosal Tunneling Endoscopic Resection for the Qualified Endoscopist in Resection of Submucosal Tumors in the Proximal Esophagus.

Invited Commentary: Submucosal Tunneling Endoscopic Resection for the Qualified Endoscopist in Resection of Submucosal Tumors in the Proximal Esophagus.

Successful Treatment of an Early Barrett's Adenocarcinoma in a High-Risk Patient with Portal Hypertension: The “Band and Leave” Strategy

Abstract“Band and leave” strategy has been described for the resection of submucosal tumors of the digestive tract to reduce the complications related to deep submucosal resection such as bleeding and perforation. We present the case of a patient with multiple comorbidities, chronic liver disease, and portal hypertension diagnosed to have T1 adenocarcinoma in Barrett's esophagus overlying a column of varix. This was successfully treated by band ligation and allowing the neoplastic mucosa to slough. We propose this technique as an alternative therapeutic option for the management of early Barrett's neoplasia in such high-risk patients with portal hypertension.

EUS-guided gastroenterostomy assisted by extrinsic abdominal compression to treat gastric obstruction after surgical resection of a GI stromal tumor.

EUS-guided gastroenterostomy is increasingly used to treat gastric outlet obstruction after surgery such as a Whipple procedure.1 Postoperative stenosis of the gastric lumen is a described adverse event after laparoscopic wedge resection of submucosal tumors located on the lesser curvature.2,3 We describe a case of EUS-guided gastroenterostomy facilitated by extrinsic abdominal compression to treat gastric obstruction resulting from a laparoscopic wedge resection of a gastrointestinal stromal tumor.

Usefulness of tumor traction with a snare and endoclips in gastric submucosal tumor resection: a propensity-score-matching analysis.

BackgroundEndoscopic resection, including endoscopic submucosal dissection (ESD) and endoscopic full-thickness resection (EFR), was used to resect small gastric submucosal tumors (SMTs). Our team explored a method of tumor traction using a snare combined with endoclips to assist in the resection of SMTs. This study aims to explore the safety and effectiveness of the method.MethodsThis research performed a propensity-score-matching (PSM) analysis to compare ESD/EFR assisted by a snare combined with endoclips (ESD/EFR with snare traction) with conventional ESD/EFR for the resection of gastric SMTs. Comparisons were made between the two groups, including operative time, en bloc resection rate, perioperative complications, and operation-related costs.ResultsA total of 253 patients with gastric SMTs resected between January 2012 and March 2019 were included in this study. PSM yielded 51 matched pairs. No significant differences were identified between the two groups in perioperative complications or the costs of disposable endoscopic surgical accessories. However, the ESD/EFR-with-snare-traction group had a shorter median operative time (39 vs 60 min, P = 0.005) and lower rate of en bloc resection (88.2% vs 100%, P = 0.027).ConclusionsESD/EFR with snare traction demonstrated a higher efficiency and en bloc resection rate for gastric SMTs, with no increases in perioperative complications and the costs of endoscopic surgical accessories. Therefore, the method seems an appropriate choice for the resection of gastric SMTs.

Sa2049 ENDOSCOPIC RESECTION FOR LEIOMYOMA OF SUBMUCOSAL TUMORS ORIGINATING FROM THE MUSCULARIS PROPRIA LAYER IN THE ESOPHAGOGASTRIC JUNCTION

The lesions in esophagogastric junction (EGJ) are difficult for treatment. The operative resection of the gastric cardia causes the diminishment of quality of life. The endoscopic treatment has been developed for the resection of submucosal tumors (SMTs). The techniques of endoscopic resection for the SMTs originating from the muscularis propria (MP) layer mainly include endoscopic submucosal dissection (ESD) and submucosal tunneling endoscopic resection (STER). The safety and efficacy of ESD and STER for EGJ SMTs has been demonstrated. We found most SMTs in EGJ are leiomyomas. The aim of the investigation was to evaluate the characteristics of leiomyomas of SMTs originating from the MP layer in EGJ by endoscopic resection. 32 patients with SMTs of the EGJ originating from the MP layer underwent ESD or STER were analyzed between March 2019 and November 2019 in a single academic medical center. The SMTs had been confirmed to be leiomyoma by pathologic evaluation .Size, adverse events, and en bloc resection rate were evaluated. 19 (59.4%) were female;17 (53.1%) were <50 years old; 19 (59.4%) underwent ESD and 13 (40.6%) underwent STER. The average maximum diameter of the lesions was 26.8 mm (range 6–90 mm). The en bloc resection rate was 93.75 % (30/32). No delayed hemorrhage or severe adverse events occurred in any of the patients following ESD. The patient with the largest tumor (90mm) which showed predominantly extraluminal growth required emergency surgery for severe bleeding in STER group. The patients with SMTs larger than or equal to 30mm were younger compared to the ones with SMTs less than 30mm (41 vs.52.6, p<0.05). The patients with leiomyomas originating from the MP layer especially larger than 30mm were young. Our study showed that endoscopic resection (ESD or STER) was safe, effective and minor invasive for the treatment of leiomyomas originating from the MP layer in the EGJ, but it seemed the large tumors with predominantly extraluminal growth should be considered prudently.

Direct endoscopic full-thickness resection for submucosal tumors with an intraluminal growth pattern originating from the muscularis propria layer in the gastric fundus

Background and aimsEndoscopic full-thickness resection (EFTR) is difficult to perform in a retroflexed fashion in the gastric fundus. The present study aims at exploring whether direct EFTR can be a simple, effective and safe procedure to treat intraluminal-growth submucosal tumors originating from the muscularis propria.MethodsThe patients with intraluminal-growth submucosal tumors originating from the muscularis propria in gastric fundus treated by direct EFTR between 01 January 2017 and 01 September 2018 were retrospectively reviewed. In addition, we analyzed the patients with intraluminal-growth submucosal tumors originating from the muscularis propria in gastric fundus treated by traditional EFTR. The differences in tumor resection time, cost-effectiveness, and complication rate were evaluated.ResultsForty patients were enrolled in the present study, 20 patients of which were in the direct EFTR group and 20 patients of which were in the traditional EFTR group. En-bloc resections of gastric tumors were successfully performed in all 40 cases. There was no significant difference in the average tumor size of the two groups (24.3 ± 2.9 mm in direct EFTR group verus 24.0 ± 2.6 mm in the traditional group, p = 0.731), but significant difference existed in the operative time between two groups (35.0 ± 8.2 min in direct EFTR group verus 130.6 ± 51.9 min in the traditional group, p<0.05). No complications, such as postoperative bleeding and perforation, occurred in any groups.ConclusionsDirect EFTR is a safe, simple and cost-effective procedure for SMTs with an intraluminal growth pattern originating from the muscularis propria layer in the gastric fundus.

Endoscopic Full Thickness Resection for Gastrointestinal Tumors - Challenges and Solutions.

Standard polypectomy, endoscopic mucosal resection, and endoscopic submucosal dissection (ESD) are established techniques for the treatment of gastrointestinal tumors. However, resection of submucosal tumors via ESD often results in low rates of microscopically margin-negative (R0) resection and high rates of perforation. Endoscopic full thickness resection (EFTR) overcomes this adverse event and aids in the therapeutic management of complex tumors.Multiple techniques for EFTR have been developed, each with its own advantages and disadvantages. Submucosal tunneling and non-exposed techniques are generally preferable, because the layer of overlying intact mucosa reduces the incidence of intraperitoneal contamination by the gastric fluid and dissemination of the tumor cells. However, adoption of EFTR by endoscopists in clinical practice remains low. The major challenge seems to be the technical difficulty in performing laparoscopic and/or endoscopic suturing using the currently available instruments.We developed a novel robotic endoscopic platform with suturing capabilities to overcome the technical challenges of suturing. This platform allows easy maneuvering and triangulation of the instruments, thus facilitating endoscopic suturing using robotic arms. Our studies have demonstrated that this robotic endoscopic platform with suturing capabilities is an effective and safe method for performing EFTR with endoscopic suturing.

2146 Combined Novel Endoscopic Techniques in Esophageal Carcinoma Management

INTRODUCTION: A variety of techniques are currently being investigated to provide optimal resection of submucosal tumors by endoscopy. Specifically, peroral endoscopic myotomy (POEM) is a form of natural orifice transluminal endoscopic procedure which was originally established as a minimally invasive technique to treat achalasia and esophageal motility disorders. Due to its success in treatment of esophageal motility disorders, certain Centers of Excellence for advanced endoscopy have expanded the use of POEM in combination with other advanced endoscopic techniques for treating esophageal cancers. In this case, we present a 69-year-old male with squamous cell cancer (SCC) in the lower third of the esophagus who was successfully treated using combined endoscopic submucosal dissection (ESD), submucosal tunneling, and POEM techniques. CASE DESCRIPTION/METHODS: A 69-year-old male with a medical history of 50-pack-year tobacco abuse, chronic alcohol use, and chronic pancreatitis was initially evaluated with EGD and EUS for anorexia, weight loss, and pancreatic cysts. Initial EGD required biopsies of nodular esophageal mucosa revealing underlying squamous cell carcinoma in situ. Repeat endoscopy 2 months later revealed a large tumor circumferentially involving 80% of the lumen in the lower esophagus. Subsequently, the patient received therapeutic intervention combining ESD and POEM techniques for tumor resection, prognostication, and symptom relief. Lesion borders were marked, and a circumferential incision was made around the lesion lifting it from the muscularis propria allowing for successfully mass excision. The submucosal dissection combined with circumferential tunneling technique allowed for complete resection of the tumor. The patient reported post-procedure symptomatic relief and was able to resume oral intake. DISCUSSION: POEM is a combination of the pre-existing endoscopic myotomy procedures in conjunction with endoscopic submucosal tunneling techniques. Although POEM is labor intensive, its application gives precision by granting access to the neoplasms without affecting deeper esophageal layers. This promising advance in gastrointestinal procedures compared to esophagectomy has shown in reported studies to offer a lower morbidity rate while providing similar cancer-free survival. Our case demonstrates successful treatment using POEM and adjunct endoscopic therapies in submucosal tunneling and submucosal tunneling endoscopic resection (STER) in the treatment of large circumferential esophageal cancer.

The efficacy of dental floss and a hemoclip as a traction method for the endoscopic full-thickness resection of submucosal tumors in the gastric fundus.

Endoscopic full-thickness resection (EFTR) provides a significant advancement to the treatment of gastrointestinal submucosal tumors (SMTs). However, technological challenges, particularly in the gastric fundus, hinder its wider application. Here, we investigated the efficacy of a simple traction method that used dental floss and a hemoclip (DFC) to facilitate EFTR. Between July 2014 and December 2016, we retrospectively reviewed data from all patients with SMTs in the gastric fundus originating from the muscularis propria layer that were treated by EFTR at Zhongshan Hospital of Fudan University. Baseline characteristics and clinical outcomes, including procedure time and complications rate, were compared between groups of patients receiving DFC-EFTR and conventional EFTR. A total of 192 patients were included in our analysis (64 in the DFC-EFTR group and 128 in the conventional EFTR group). Baseline characteristics for the two groups were similar. The mean time for DFC-EFTR and conventional EFTR was 44.2 ± 24.4 and 54.2 ± 33.2min, respectively (P = 0.034). Although no serious adverse events presented in any of our cases, post-EFTR electrocoagulation syndrome (PEECS), as a minor complication, was less frequent in the DFC-EFTR group (3.1% vs. 12.5%, P = 0.036). Univariate and multivariate analysis identified that DFC, when used in EFTR, played a significant role in reducing procedure time and the rate of PEECS. The mean procedure time was significantly shorter in the DFC-EFTR group for lesions over 1.0cm (P = 0.005), when the lesions were located in the greater curvature of the gastric fundus (P = 0.025) or when the lesions presented with intraluminal growth (P = 0.032). Moreover, when EFTR was carried out by experts, the mean procedure time was 20.4% shorter in the DFC-EFTR group (P = 0.038). This study indicated that DFC-EFTR for SMTs in the gastric fundus resulted in a shorter procedure time and reduced the risk of PEECS, a minor complication.

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

The clinical success of per-oral endoscopic myotomy (POEM) has led to the development of a new field of 'submucosal endoscopy'. This study aimed to evaluate the safety, efficacy, and limitations of per-oral endoscopic tumor resection (POET) in the management of submucosal tumors (SMTs) in the esophagus and the gastric cardia. POET was performed in 47 patients from January 2011 to December 2017. The indication for POET was SMTs≤30mm in minor axis diameter. Patient and tumor characteristics (age, gender, tumor location, size, and histology), operative and clinical results of POET (procedure time and completion rate, en bloc resection rate, length of hospitalization, adverse events and tumor recurrence) were analyzed retrospectively. POET was successfully completed in 43 patients (91.5%) without any major adverse events (Clavien-Dindo IIIb-IV). Four patients required conversion to an open surgical procedure due to suboptimal visualization during POET. Four patients underwent piecemeal resection of their SMTs including GISTs. Median follow-up was 44months (10-96months), during that time, there were no incidences of tumor recurrence. Tumors that had a minor axis diameter>30mm or a tumor mass index (TMI) [major axis diameter (mm)×minor axis diameter (mm)] >1000 had a high likelihood of being converted to surgical resection. POET is a safe and effective treatment for SMTs. However, in patients where the minor axis diameter is>30mm or the TMI>1000, surgical excision should be considered. Furthermore, application of POET for SMTs with malignant potential should be carefully considered to ensure optimal oncologic outcomes.

“An Odyssey of Third Space Endoscopy”—from Entry into the Tunnel to Entry into the Peritoneal Cavity

AbstractThe last decade has seen the growth of a completely new and exciting entity called the third space endoscopy (TSE) that has brought about a paradigm shift in the way we manage various disorders of the gastrointestinal tract. The journey started with per oral endoscopic myotomy (POEM) for achalasia cardia and within a decade the concept has been exploited to its best potential for disorders including submucosal tumor resection, pyloromyotomy for gastroparesis, complete division of septum without the risk of perforation in diverticular diseases of esophagus, restoration of esophageal lumen in long strictures, restoration of bowel movement in Hirschsprung’s disease, and then taking the concept to the next level of pure NOTES (natural orifice transluminal endoscopic surgery) by entering the peritoneal cavity and performing fundoplication. This review will discuss the history of TSE with brief discussion about the various applications and what has been achieved till present.

Laparoscopic endoscopic cooperative surgery (LECS) for the gastrointestinal tract: Updated indications.

Laparoscopic and endoscopic cooperative surgery (LECS) is a procedure combining laparoscopic gastric resection with endoscopic submucosal dissection for local resection of gastric tumors with appropriate, minimal surgical resection margins. The LECS concept was initially developed from the classical LECS procedure for gastric submucosal tumor resection. Many researchers reported that classical LECS was a safe and feasible technique for resection of gastric submucosal tumors, regardless of tumor location, including the esophagogastric junction. Recently, LECS was approved for insurance coverage by Japan's National Health Insurance plan and widely applied for gastric submucosal tumor resection. However, the limitations of classical LECS are the risk of abdominal infection, scattering of tumor cells in the abdominal cavity, and tumor cell seeding in the peritoneum. The development of modified LECS procedures, such as inverted‐LECS, non‐exposed endoscopic wall‐inversion surgery, a combination of laparoscopic and endoscopic approaches to neoplasia with a non‐exposure technique, and closed‐LECS, has almost resolved these drawbacks. This has led to a recent increase in the indication of modified LECS to include patients with gastric epithelial neoplasms. The LECS concept is also beginning to be applied to tumor excision in other organs, such as the duodenum, colon and rectum. Further evolution of LECS procedures is expected in the future. Sentinel lymph node mapping could also be combined with LECS, resulting in a portion of early gastric cancers being treated by LECS with sentinel node mapping.

Role of EUS to Affect Treatment Strategy in Endoscopic Resection of Submucosal Tumors

Role of EUS to Affect Treatment Strategy in Endoscopic Resection of Submucosal Tumors

Clinical Values of Dental Floss Traction Assistance in Endoscopic Full-Thickness Resection for Submucosal Tumors Originating from the Muscularis Propria Layer in the Gastric Fundus.

Endoscopic full-thickness resection (EFTR) derived from endoscopic submucosal dissection has gradually been accepted and even promoted for the treatment of submucosal tumors (SMTs) originating from the muscularis propria (MP) layer. However, there are some difficulties when EFTR is used to treat MP lesions in the gastric fundus. This study intends to explore whether EFTR can be made simpler, safer, and more effective with the traction assistance of dental floss. The clinical data of patients (trial group) with lesions in the MP layer in the gastric fundus undergoing EFTR with traction assistance of dental floss at Zhongshan Hospital, in 2016, were reviewed retrospectively. The control group was matched with the trial group according to tumor size. The differences in tumor resection time, patient hospitalization time, and complication rate were evaluated. There was no significant difference in the average age of the two groups, each of which comprised 24 cases (58.7 ± 11.8 years versus 56.6 ± 7.9 years, t = 0.663, P = .511). However, there was a statistically significant difference in the operative time between the two groups (10.8 ± 2.8 minutes versus 19.0 ± 4.7 minutes, t = 7.298, P < .05). There was no statistically significant difference in the length of the postoperative hospital stay (3.2 ± 0.5 days versus 3.2 ± 0.5 days, t = 0.291, P = .772). In the trial group, there were 19 cases of gastrointestinal stromal tumors (group 1) and 5 cases of leiomyoma. The control group had similar results. Neither group experienced postoperative delayed bleeding, perforation, or other complications. When EFTR is used to treat SMTs originating from the MP in the gastric fundus, dental floss traction assistance can relieve the tumor boundary to simplify the surgical procedure and save the operation time.

Endoscopic Treatment of Subepithelial Lesions of the Gastrointestinal Tract.

Purpose of Review The study aimed to discuss novel endoscopic approaches to resection of submucosal lesions. Recent Findings Endoscopic resection by excavation, full-thickness resection, and submucosal tunneling are by now well-documented techniques for submucosal tumor resection. Combined approaches with laparoscopy such as several variations of laparoscopic endoscopic cooperation surgery (LECS) and non-exposed wall-inversion surgery (NEWS) are also possible now. Reports of these approaches show good results. However, lesion size is the main limitation to these approaches. Summary Endoscopic submucosal tumor resection can be effectively done endoscopically or by endoscopy combined with laparoscopy. These techniques allow localized resection of lesions at difficult locations such as in the gastroesophageal junction with limited influence on the normal anatomy. Variations in techniques are being practiced worldwide striving to achieve complete resection with minimal disturbance of function or contamination. The choice between approaches depends largely on the size and site of the lesion and expertise available.

Submucosal Tunneling Endoscopic Resection vs Thoracoscopic Enucleation for Large Submucosal Tumors in the Esophagus and the Esophagogastric Junction

Submucosal tunneling endoscopic resection (STER) is regarded as a promising method for resection of submucosal tumors (SMTs); however, little is known about a comprehensive comparison of STER and thoracoscopic enucleation (TE). The aim of this study was to compare the clinical outcomes of STER and TE for large symptomatic SMTs in the esophagus and esophagogastric junction, as well as to analyze the factors that affect the feasibility and safety of STER. We enrolled 166 patients with large symptomatic SMTs in the esophagus and esophagogastric junction from September 2011 to March 2016 in this retrospective study. The clinicopathologic features and treatment results were collected and analyzed. En bloc resection was achieved in 84.6% of the patients in the STER group and 86.7% of the patients in the TE group (p= 0.708). Notably, the procedure time and hospital stay in the STER group were considerably shorter than those in the TE group. Tumor transverse diameter is a significant risk factor for piecemeal resection, adverse events, and technical difficulties. No recurrence or metastasis was found during a mean follow-up period of more than 2 years. Submucosal tunneling endoscopic resection is effective and safe for large SMTs in the esophagus and esophagogastric junction. This procedure has the advantage of being more minimally invasive with a shorter procedure time and hospital stay compared with TE. Submucosal tunneling endoscopic resection for tumors with a transverse diameter ≥3.5cm and an irregular shape is associated with relatively high risk for piecemeal resection, adverse events, and technical difficulties.

Effect of submucosal tunneling endoscopic resection for submucosal tumors at esophagogastric junction and risk factors for failure of en bloc resection.

Most submucosal tumors (SMTs) in the esophagogastric junction (EGJ) are irregularly shaped and different from those in the esophagus, where submucosal tunneling endoscopic resection (STER) has been proven effective and safe. However, few reports paid attention to STER for SMTs in the EGJ. The aim of the study was not only to evaluate the effect of STER in patients with SMTs in the EGJ but to analyze the risk factors for failure ofen bloc resection. A consecutive of 47 patients with SMTs originating from the muscularis propria (MP) layer in the EGJ underwent STER were retrospectively included between September 2012 and December 2016. Thirty-five tumors underwent en bloc resection, and the other 12 tumors received piecemeal resection. The tumor size, operation time, en bloc resection rate, complications, residual, and local recurrence were achieved and compared between the two groups. Forty-six of 47 lesions (97.9%) were successfully resected. The mean lesion size was 29.7±16.3mm. Both the en bloc resection rate and complete resection rate were 74.5% (35/47). No severe complications occurred in the 47 patients. Patients in the piecemeal resection group had more irregularly shaped lesions, longer tumor diameter, larger tumor size (≥40mm), longer operation time, and longer hospital stay after procedure (P<0.05), and there were no statistically differences between the two groups in in-operativecomplications, post-operative complications, and residual rate (P>0.05). By univariate analysis and stepwise logistic regression analysis, irregular shape and tumor diameter≥20mm were two risk factors for failure ofen bloc resection. STER is an effective and safe technique for the treatment of SMTs arising from the MP layer in the EGJ. Irregular shape and tumor diameter≥20mm are the reliable risk factors for en bloc resection failure.