A feasibility study on utilizing machine learning technology to reduce the costs of gastric cancer screening in Taizhou, China.

Aim: To optimize gastric cancer screening score and reduce screening costs using machine learning models. Methods: This study included 228,634 patients from the Taizhou Gastric Cancer Screening Program. We used three machine learning models to optimize Li's gastric cancer screening score: Gradient Boosting Machine (GBM), Distributed Random Forest (DRF), and Deep Learning (DL). The performance of the binary classification models was evaluated using the area under the curve (AUC) and area under the precision-recall curve (AUCPR). Results: In the binary classification model used to distinguish low-risk and moderate- to high-risk patients, the AUC in the GBM, DRF, and DL full models were 0.9994, 0.9982, and 0.9974, respectively, and the AUCPR was 0.9982, 0.9949, and 0.9918, respectively. Excluding Helicobacter pylori IgG antibody, pepsinogen I, and pepsinogen II, the AUC in the GBM, DRF, and DL models were 0.9932, 0.9879, and 0.9900, respectively, and the AUCPR was 0.9835, 0.9716, and 0.9752, respectively. Remodel after removing variables IgG, PGI, PGII, and G-17, the AUC in GBM, DRF, and DL was 0.8524, 0.8482, 0.8477, and AUCPR was 0.6068, 0.6008, and 0.5890, respectively. When constructing a tri-classification model, we discovered that none of the three machine learning models could effectively distinguish between patients at intermediate and high risk for gastric cancer (F1 scores in the GBM model for the low, medium and high risk: 0.9750, 0.9193, 0.5334, respectively; F1 scores in the DRF model for low, medium, and high risks: 0.9888, 0.9479, 0.6694, respectively; F1 scores in the DL model for low, medium, and high risks: 0.9812, 0.9216, 0.6394, respectively). Conclusion: We concluded that gastric cancer screening indicators could be optimized when distinguishing low-risk and moderate to high-risk populations, and detecting gastrin-17 alone can achieve a good discriminative effect, thus saving huge expenditures.

Hybrid argon plasma coagulation for the treatment of Barrett's esophagus: A prospective, multicenter study.

BACKGROUND: The incidence of Barrett's esophagus (BE) in China is lower compared to the Western populations. Hence, studies conducted in the Chinese population has been limited. The current treatment options available for BE treatment includes argon plasma coagulation (APC), radiofrequency ablation and cryoablation, all with varying degrees of success. AIM: To determine the efficacy and safety of HybridAPC in the treatment of BE. METHODS: The study cohort consisted of patients with BE who underwent HybridAPC ablation treatment. These procedures were performed by seven endoscopists from different tertiary hospitals. The duration of the procedure, curative rate, complications and recurrent rate by 1-year follow-up were recorded. RESULTS: Eighty individuals were enrolled for treatment from July 2017 to June 2020, comprising of 39 males and 41 females with a median age of 54 years (range, 30 to 83 years). The technical success rate of HybridAPC was 100% and the overall curative rate was 98.15%. No severe complications occurred during the operation. BE cases were classified as short-segment BE and long-segment BE. Patients with short-segment BE were all considered cured without complications. Thirty-six patients completed the one-year follow-up without recurrence. Twenty-four percent had mild dysplasia which were all resolved with one post-procedural treatment. The mean duration of the procedure was 10.94 ± 6.52 min. CONCLUSION: Treatment of BE with HybridAPC was found to be a simple and quick procedure that is safe and effective during the short-term follow-up, especially in cases of short-segment BE. This technique could be considered as a feasible alternative ablation therapy for BE.

Deep learning assists detection of esophageal cancer and precursor lesions in a prospective, randomized controlled study.

Endoscopy is the primary modality for detecting asymptomatic esophageal squamous cell carcinoma (ESCC) and precancerous lesions. Improving detection rate remains challenging. We developed a system based on deep convolutional neural networks (CNNs) for detecting esophageal cancer and precancerous lesions [high-risk esophageal lesions (HrELs)] and validated its efficacy in improving HrEL detection rate in clinical practice (trial registration ChiCTR2100044126 at www.chictr.org.cn). Between April 2021 and March 2022, 3117 patients ≥50 years old were consecutively recruited from Taizhou Hospital, Zhejiang Province, and randomly assigned 1:1 to an experimental group (CNN-assisted endoscopy) or a control group (unassisted endoscopy) based on block randomization. The primary endpoint was the HrEL detection rate. In the intention-to-treat population, the HrEL detection rate [28 of 1556 (1.8%)] was significantly higher in the experimental group than in the control group [14 of 1561 (0.9%), P = 0.029], and the experimental group detection rate was twice that of the control group. Similar findings were observed between the experimental and control groups [28 of 1524 (1.9%) versus 13 of 1534 (0.9%), respectively; P = 0.021]. The system's sensitivity, specificity, and accuracy for detecting HrELs were 89.7, 98.5, and 98.2%, respectively. No adverse events occurred. The proposed system thus improved HrEL detection rate during endoscopy and was safe. Deep learning assistance may enhance early diagnosis and treatment of esophageal cancer and may become a useful tool for esophageal cancer screening.

Developing a Prognostic Model for Primary Biliary Cholangitis Based on a Random Survival Forest Model.

Background: Primary biliary cholangitis (PBC) is a rare autoimmune liver disease with few effective treatments and a poor prognosis, and its incidence is on the rise. There is an urgent need for more targeted treatment strategies to accurately identify high-risk patients. The use of stochastic survival forest models in machine learning is an innovative approach to constructing a prognostic model for PBC that can improve the prognosis by identifying high-risk patients for targeted treatment. Method: Based on the inclusion and exclusion criteria, the clinical data and follow-up data of patients diagnosed with PBC-associated cirrhosis between January 2011 and December 2021 at Taizhou Hospital of Zhejiang Province were retrospectively collected and analyzed. Data analyses and random survival forest model construction were based on the R language. Result: Through a Cox univariate regression analysis of 90 included samples and 46 variables, 17 variables with p-values <0.1 were selected for initial model construction. The out-of-bag (OOB) performance error was 0.2094, and K-fold cross-validation yielded an internal validation C-index of 0.8182. Through model selection, cholinesterase, bile acid, the white blood cell count, total bilirubin, and albumin were chosen for the final predictive model, with a final OOB performance error of 0.2002 and C-index of 0.7805. Using the final model, patients were stratified into high- and low-risk groups, which showed significant differences with a P value <0.0001. The area under the curve was used to evaluate the predictive ability for patients in the first, third, and fifth years, with respective results of 0.9595, 0.8898, and 0.9088. Conclusion: The present study constructed a prognostic model for PBC-associated cirrhosis patients using a random survival forest model, which accurately stratified patients into low- and high-risk groups. Treatment strategies can thus be more targeted, leading to improved outcomes for high-risk patients.

Development and validation of LightGBM algorithm for optimizing of Helicobacter pylori antibody during the minimum living guarantee crowd based gastric cancer screening program in Taizhou, China.

Gastric cancer continues to be a significant health concern in China, with a high incidence rate. To mitigate its impact, early detection and treatment is key. However, conducting large-scale endoscopic gastric cancer screening is not feasible in China. Instead, a more appropriate approach would be to initially screen high-risk groups and follow up with endoscopic testing as needed. We conducted a study on 25,622 asymptomatic participants aged 45-70 years from a free gastric cancer screening program in the Taizhou city government's Minimum Living Guarantee Crowd (MLGC) initiative. Participants completed questionnaires, blood tests, and underwent gastrin-17 (G-17), pepsinogen I and II (PGI and PGII), and H. pylori IgG antibody (IgG) assessments. Using the light gradient boosting machine (lightGBM) algorithm, we developed a predictive model for gastric cancer risk. In the full model, F1 score was 2.66%, precision was 1.36%, and recall was 58.14%. In the high-risk model, F1 score was 2.51%, precision was 1.27%, and recall was 94.55%. Excluding IgG, the F1 score was 2.73%, precision was 1.40%, and recall was 68.62%. We conclude that H. pylori IgG appears to be able to be excluded from the prediction model without significantly affecting its performance, which is important from a health economic point of view. It suggests that screening indicators can be optimized, and expenditures reduced. These findings can have important implications for policymakers, as we can focus resources on other important aspects of gastric cancer prevention and control.

Role of ferroptosis in colorectal cancer.

Colorectal cancer (CRC) is the second deadliest cancer and the third-most common malignancy in the world. Surgery, chemotherapy, and targeted therapy have been widely used to treat CRC, but some patients still develop resistance to these treatments. Ferroptosis is a novel non-apoptotic form of cell death. It is an iron-dependent non-apoptotic cell death characterized by the accumulation of lipid reactive oxygen species and has been suggested to play a role in reversing resistance to anticancer drugs. This review summarizes recent advances in the prognostic role of ferroptosis in CRC and the mechanism of action in CRC.

Clinical manifestation and treatment of small intestinal lymphangioma: A single center analysis of 15 cases.

Background: Small intestinal lymphangioma is a very rare benign lesion. Thus far, the literature on small intestinal lymphangioma has mainly involved case reports. The present study retrospectively examined the clinical features of patients with a pathological diagnosis of small intestinal lymphangioma. Materials and methods: From January 2010 to January 2021, 15 patients were pathologically diagnosed with small intestinal lymphangioma. The age, gender, clinical manifestation, computed tomography (CT) findings, endoscopic findings, localization of the lesion, treatment method, complications, and follow-up were retrospectively analyzed. Results: Most of the patients had no symptoms, and those with symptoms had melena or abdominal pain. Lymphangioma was located in the duodenum in nine cases (60.0%), jejunum in two (13.3%), jejunal-ileal junction with mesentery involvement in one (6.7%) and ileum in three (20.0%). Three cases (20.0%) had multiple lesions, and the other 12 (80.0%) had single lesions. The median size of the lesions was 0.8 cm. Thirteen cases were found by endoscopy, and nine cases of them had white-colored spots on the surface. Ten cases (66.7%) underwent endoscopic treatment, three (20.0%) underwent surgical treatment, and two (13.3%) were followed up. Postoperative acute pancreatitis developed in one patient after endoscopic resection of duodenal papillary lymphangioma; postoperative abdominal bleeding occurred in one patient with jejunal lymphangioma who underwent partial small bowel resection. Conclusion: Small intestinal lymphangioma is extremely rare, and its clinical manifestations are non-specific. Endoscopy is of great value in the diagnosis of small intestinal lymphangioma. Depending on the clinical manifestations, the size, location and scope of the lesions, follow-up, endoscopic treatment and surgery can be selected.

The Feasibility of Applying Artificial Intelligence to Gastrointestinal Endoscopy to Improve the Detection Rate of Early Gastric Cancer Screening.

Convolutional neural networks in the field of artificial intelligence show great potential in image recognition. It assisted endoscopy to improve the detection rate of early gastric cancer. The 5-year survival rate for advanced gastric cancer is less than 30%, while the 5-year survival rate for early gastric cancer is more than 90%. Therefore, earlier screening for gastric cancer can lead to a better prognosis. However, the detection rate of early gastric cancer in China has been extremely low due to many factors, such as the presence of gastric cancer without obvious symptoms, difficulty identifying lesions by the naked eye, and a lack of experience among endoscopists. The introduction of artificial intelligence can help mitigate these shortcomings and greatly improve the accuracy of screening. According to relevant reports, the sensitivity and accuracy of artificial intelligence trained on deep cirrocumulus neural networks are better than those of endoscopists, and evaluations also take less time, which can greatly reduce the burden on endoscopists. In addition, artificial intelligence can also perform real-time detection and feedback on the inspection process of the endoscopist to standardize the operation of the endoscopist. AI has also shown great potential in training novice endoscopists. With the maturity of AI technology, AI has the ability to improve the detection rate of early gastric cancer in China and reduce the death rate of gastric cancer related diseases in China.

Esophageal Mucosal Autograft for Preventing Stricture After Widespread Endoscopic Submucosal Dissection of Superficial Esophageal Lesions.

BACKGROUND: Although esophageal mucosal autograft prevents esophageal stricture after widespread endoscopic submucosal dissec- tion and has been reported as a new technique, it is relatively unproven in clinical practice. This prospective study was conducted to evaluate our experience using esophageal mucosal autograft to prevent strictures after widespread endoscopic submucosal dissection in patients with widespread superficial esophageal lesions. METHODS: Between October 2017 and June 2018, 15 patients with widespread superficial esophageal lesions were consecutively treated with widespread endoscopic submucosal dissection and then underwent esophageal mucosal autograft. The main outcomes measured included esophageal epithelialization and esophageal stricture. RESULTS: The median longitudinal diameter of the widespread superficial esophageal lesions was 5.2 cm. All 15 patients were success- fully treated with widespread endoscopic submucosal dissection and esophageal mucosal autograft, and the median procedural time was 182 minutes. During follow-up (median, 23 months), esophageal epithelialization was found in 13 patients (86.7%), and 7 patients experienced esophageal stricture (46.7%). In those 7 patients, the esophageal strictures were successfully relieved after endoscopic bal- loon dilation or endoscopic radial incision. No complications related to endoscopic balloon dilation/endoscopic radial incision occurred. Additionally, local recurrence was found in 1 patient with poorly differentiated squamous cell carcinoma, and further surgical resection was performed. CONCLUSIONS: Esophageal mucosal autograft appears to be an efficient approach to reconstructing local esophageal epithelium and might have a potential role in preventing esophageal stricture after widespread endoscopic submucosal dissection. However, as a new technique, it needs more improvement to enhance its role in preventing esophageal stricture after widespread endoscopic submucosal dissection.

Reactive Oxygen Species Induce Fatty Liver and Ischemia-Reperfusion Injury by Promoting Inflammation and Cell Death.

Liver transplantation is the ultimate method for treating end-stage liver disease. With the increasing prevalence of obesity, the number of patients with non-alcoholic fatty liver, a common cause of chronic liver disease, is on the rise and may become the main cause of liver transplantation in the future. With the increasing gap between the number of donor livers and patients waiting for liver transplantation and the increasing prevalence of non-alcoholic fatty liver, the proportion of steatosis livers among non-standard donor organs is also increasing. Ischemia-reperfusion injury has historically been the focus of attention in the liver transplantation process, and severe ischemia-reperfusion injury leads to adverse outcomes of liver transplantation. Studies have shown that the production of reactive oxygen species and subsequent oxidative stress play a key role in the pathogenesis of hepatic ischemia and reperfusion injury and non-alcoholic fatty liver. Furthermore, the sensitivity of fatty liver transplantation to ischemia-reperfusion injury has been suggested to be related to the production of reactive oxygen species (ROS) and oxidative stress. In ischemia-reperfusion injury, Kupffer cell and macrophage activation along with mitochondrial damage and the xanthine/xanthine oxidase system promote marked reactive oxygen species production and the inflammatory response and apoptosis, resulting in liver tissue injury. The increased levels of ROS and lipid peroxidation products, vicious circle of ROS and oxidative stress along with mitochondrial dysfunction promoted the progress of non-alcoholic fatty liver. In contrast to the non-fatty liver, a non-alcoholic fatty liver produces more reactive oxygen species and suffers more serious oxidative stress when subjected to ischemia-reperfusion injury. We herein review the effects of reactive oxygen species on ischemia-reperfusion injury and non-alcoholic fatty liver injury as well as highlight several treatment approaches.

The Influence of Microenvironment on Survival of Intraportal Transplanted Islets.

Clinical islet transplantation has the potential to cure type 1 diabetes. Despite recent therapeutic success, it is still uncommon because transplanted islets are damaged by multiple challenges, including instant blood mediated inflammatory reaction (IBMIR), inflammatory cytokines, hypoxia/reperfusion injury, and immune rejection. The transplantation microenvironment plays a vital role especially in intraportal islet transplantation. The identification and targeting of pathways that function as "master regulators" during deleterious inflammatory events after transplantation, and the induction of immune tolerance, are necessary to improve the survival of transplanted islets. In this article, we attempt to provide an overview of the influence of microenvironment on the survival of transplanted islets, as well as possible therapeutic targets.

Cost-effective low-coverage whole-genome sequencing assay for the risk stratification of gastric cancer.

BACKGROUND: Gastric cancer (GC), a multifactorial disease, is caused by pathogens, such as Helicobacter pylori (H. pylori) and Epstein-Barr virus (EBV), and genetic components. AIM: To investigate microbiomes and host genome instability by cost-effective, low-coverage whole-genome sequencing, as biomarkers for GC subtyping. METHODS: Samples from 40 GC patients were collected from Taizhou Hospital, Zhejiang Province, affiliated with Wenzhou Medical University. DNA from the samples was subjected to low-coverage whole-genome sequencing with a median genome coverage of 1.86 × (range: 1.03 × to 3.17 ×) by Illumina × 10, followed by copy number analyses using a customized bioinformatics workflow ultrasensitive chromosomal aneuploidy detector. RESULTS: Of the 40 GC samples, 20 (50%) were found to be enriched with microbiomes. EBV DNA was detected in 5 GC patients (12.5%). H. pylori DNA was found in 15 (37.5%) patients. The other 20 (50%) patients were found to have relatively higher genomic instability. Copy number amplifications of the oncogenes, ERBB2 and KRAS, were found in 9 (22.5%) and 7 (17.5%) of the GC samples, respectively. EBV enrichment was found to be associated with tumors in the gastric cardia and fundus. H. pylori enrichment was found to be associated with tumors in the pylorus and antrum. Tumors with elevated genomic instability showed no localization and could be observed in any location. Additionally, H. pylori-enriched GC was found to be associated with the Borrmann type II/III and gastritis history. EBV-enriched GC was not associated with gastritis. No statistically significant correlation was observed between genomic instability and gastritis. Furthermore, these three different molecular subtypes showed distinct survival outcomes (P = 0.019). EBV-positive tumors had the best prognosis, whereas patients with high genomic instability (CIN+) showed the worst survival. Patients with H. pylori infection showed intermediate prognosis compared with the other two subtypes. CONCLUSION: Thus, using low-coverage whole-genome sequencing, GC can be classified into three categories based on disease etiology; this classification may prove useful for GC diagnosis and precision medicine.

Feasibility of endoscopic resection without laparoscopic assistance for giant gastric subepithelial tumors originating from the muscularis propria layer (with video).

BACKGROUND AND AIMS: Currently, published data of endoscopic resection (ER) for giant (≥ 6 cm) gastric subepithelial tumors originating from the muscularis propria layer (MP-SETs) are extremely rare and limited to only case reports. The aim of this study was thus to assess the feasibility of using ER for giant (≥ 6 cm) gastric MP-SETs in a case series. METHODS: Between July 2013 and December 2020, a total of 23 patients with giant (≥ 6 cm) gastric MP-SETs were treated with ER in the endoscopic center of Taizhou hospital. The study assessed outcomes of en bloc resection, complete resection, total complications, and local residual/recurrence of tumors. RESULTS: The mean procedure time was 112.2 min. En bloc resection was achieved in 22 tumors (95.7%). En bloc removal from the stomach and complete resection were achieved in 6 patients (26.1%). The rate of complete resection differed significantly depending on the minimum tumor diameter (P < 0.001). During hospitalization, 4 patients had complications, including localized peritonitis (3/23, 13.0%) and pulmonary infection (1/23, 4.3%). These 4 patients recovered successfully after conservative medical treatment. Histopathological examination revealed that 18 tumors were gastrointestinal stromal tumors (GISTs), and 5 tumors were leiomyoma. No patients were observed to have residual or recurrent tumors during the follow-up. CONCLUSIONS: Although ER for giant (≥ 6 cm) gastric MP-SETs was associated with several technical challenges and a relatively low complete resection rate, this technique was found to be a feasible therapeutic method for selected patients with a giant (≥ 6 cm) gastric MP-SETs when performed by an experienced endoscopic team.

Feasibility of transgastric endoscopic gallbladder-preserving surgery for benign gallbladder diseases (with video).

BACKGROUND: With the increasing realization of the importance of gallbladder function, choledochoscopic gallbladder-preserving surgery has been advocated for benign gallbladder diseases. However, limited information is available regarding the use of endoscopic gallbladder-preserving surgery (EGPS) for patients with benign gallbladder diseases. The aim of this study was to evaluate the feasibility of EGPS for benign gallbladder diseases. METHODS: Between June 2020 and January 2021, 22 patients with gallbladder stones and/or gallbladder polyps were treated with EGPS. The main outcome measures included the rate of complications, residual gallbladder stones, and gallbladder stone recurrence. RESULTS: In this study, transgastric EGPS was successfully performed in 22 patients (13 female, 9 male) with benign gallbladder diseases, and included 8 cases of multiple gallstones, 4 cases of gallbladder polyps with gallstones, 6 cases of multiple gallbladder polyps, 2 cases of single gallstone, and 2 case of singe gallbladder polyp. The median time of transgastric EGPS was 118 min. During hospitalization, 4 patients suffered localized peritonitis (4/22, 18.2%), and these patients successfully recovered after conservative medical treatment. None of the patients experienced massive bleeding, delayed bleeding, diffuse peritonitis, or any other serious complications. During the median follow-up of 4 months, 1 patient suffered residual gallstone, while no gallstone recurrence or deaths related to transgastric EGPS occurred in any patients. CONCLUSIONS: Transgastric EGPS appears to be a feasible treatment method in selected patients with benign gallbladder diseases. However, as it is a new technique, further studies are needed to explore the long-term effectiveness of transgastric EGPS.

Transplantation of acellularized dermis matrix (ADM) plus fully covered metal stent to prevent stricture after circumferential endoscopic submucosal dissection of early esophageal cancer (with video).

BACKGROUD AND STUDY AIMS: Esophageal stricture is a serious adverse event occurring after circular endoscopic submucosal dissection (ESD) involving the whole esophagus. However, there is still a lack of effectively preventive methods. The main purpose of this study is to evaluate the efficacy of application of acellularized dermis matrix (ADM) for the prevention of post-ESD esophageal stricture. The main objective of this study was to evaluate the use of decellularized dermal matrix (ADM) in the prevention of post-esophageal ESD strictures. PATIENTS AND METHODS: A pilot, single-center, prospective study was conducted. The study enrolled seven patients who had high-risks with extended resection of developing post-ESD esophageal stricture. After undergoing ESD, we attached different size of ADM patches to the mucosal defects using titanium clips then fixed with a metal mesh stent. The stent covered with metal mesh was removed at the median time of 27 days after the endoscopic procedure. Follow-up and repeated outpatient endoscopic screening were performed at appropriate scheduled times. RESULTS: The average longitudinal diameter of the resected specimens was 58.3 mm (range 38-90 mm). There were three patients developing strictures postoperatively at a mean time of 87 days (range 42-140). The median number of postoperative endoscopic balloon dilatation (EBD) in patients with stenosis was 2 (range 2-9). There were no deaths during a median follow-up period of 6 moths (range 1-12). CONCLUSIONS: This study was performed to assess the efficacy and safe method of relieving the severity of esophageal stricture after ESD through transplantation of ADM.

Role of the Microenvironment in Mesenchymal Stem Cell-Based Strategies for Treating Human Liver Diseases.

Liver disease is a severe health problem that endangers human health worldwide. Mesenchymal stem cell (MSC) therapy is a novel treatment for patients with different liver diseases due to its vast expansion potential and distinctive immunomodulatory properties. Despite several preclinical trials having confirmed the considerable efficacy of MSC therapy in liver diseases, the questionable safety and efficacy still limit its application. As a precursor cell, MSCs can adjust their characteristics in response to the surrounding microenvironment. The microenvironment provides physical and chemical factors essential for stem cell survival, proliferation, and differentiation. However, the mechanisms are still not completely understood. We, therefore, summarized the mechanisms underlying the MSC immune response, especially the interaction between MSCs and the liver microenvironment, discussing how to achieve better therapeutic effects.

Effectiveness and safety of over-the-scope clip in closing perforations after duodenal surgery.

BACKGROUND: Endoscopic resection of duodenal subepithelial lesions (SELs) is a difficult procedure with a high risk of perforation. At present, dealing with perforation after endoscopic resection of duodenal SELs is still considered a great challenge. AIM: To evaluate the effectiveness and safety of an over-the-scope clip (OTSC) in the treatment of perforation post-endoscopic resection of duodenal SELs. METHODS: From May 2015 to November 2019, 18 patients with perforation following endoscopic resection of duodenal SELs were treated with OTSCs. Data comprising the rate of complete resection, closure of intraprocedural perforation, delayed bleeding, delayed perforation, and postoperative infection were extracted. RESULTS: The rate of complete removal of duodenal SELs and successful closure of the perforation was 100%. The median perforation size was 1 cm in diameter. Seventeen patients had minor intraoperative bleeding, while the remaining 1 patient had considerable amount of bleeding during the procedure. Seven patients had postoperative abdominal infections, of which 1 patient developed an abscess in the right iliac fossa and another patient developed septic shock. All 18 patients recovered and were discharged. No delayed bleeding or perforation was reported. The mean time taken to resume normal diet after the procedure was 6.5 d. The mean postoperative hospital stay was 9.5 d. No residual or recurrent lesions were detected during the follow-up period (15-66 mo). CONCLUSION: Closing a perforation after endoscopic resection of duodenal SELs with OTSCs seems to be an effective and reasonably safe therapeutic method.