Feasibility of a novel unassisted single-channel transcolonic endoscopic appendectomy for the treatment of appendiceal lesions (with video).

BACKGROUND: Transcolonic endoscopic appendectomy (TEA) is rapidly evolving and has been reported as a minimally invasive alternative to appendectomy. We aimed to characterize the feasibility and safety of a novel unassisted single-channel TEA. METHOD: We retrospectively investigated 23 patients with appendicitis or appendiceal lesions who underwent TEA from February 2016 to December 2022. We collected clinicopathological characteristics, procedure­related parameters, and follow­up data and analyzed the impact of previous abdominal surgery and traction technique. RESULTS: The mean age was 56.0 years. Of the 23 patients with appendiceal lesions, fourteen patients underwent TEA and nine underwent traction-assisted TEA (T-TEA). Eight patients (34.8%) had previous abdominal surgery. The En bloc resection rate was 95.7%. The mean procedure duration was 91.1 ± 45.5 min, and the mean wound closure time was 29.4 ± 18.6 min. The wounds after endoscopic appendectomy were closed with clips (21.7%) or a combination of clip closure and endoloop reinforcement (78.3%), and the median number of clips was 7 (range, 3-15). Three patients (13.0%) experienced major adverse events, including two delayed perforations (laparoscopic surgery) and one infection (salvage endoscopic suture). During a median follow-up of 23 months, no residual or recurrent lesions were observed, and no recurrence of abdominal pain occurred. There were no significant differences between TEA and T-TEA groups and between patients with and without abdominal surgery groups in each factor. CONCLUSION: Unassisted single-channel TEA for patients with appendiceal lesions has favorable short- and long-term outcomes. TEA can safely and effectively treat appendiceal disease in appropriately selected cases.

An Automated Video Analysis System for Retrospective Assessment and Real-Time Monitoring of Endoscopic Procedures (with Video).

BACKGROUND AND AIMS: Accurate recognition of endoscopic instruments facilitates quantitative evaluation and quality control of endoscopic procedures. However, no relevant research has been reported. In this study, we aimed to develop a computer-assisted system, EndoAdd, for automated endoscopic surgical video analysis based on our dataset of endoscopic instrument images. METHODS: Large training and validation datasets containing 45,143 images of 10 different endoscopic instruments and a test dataset of 18,375 images collected from several medical centers were used in this research. Annotated image frames were used to train the state-of-the-art object detection model, YOLO-v5, to identify the instruments. Based on the frame-level prediction results, we further developed a hidden Markov model to perform video analysis and generate heatmaps to summarize the videos. RESULTS: EndoAdd achieved high accuracy (>97%) on the test dataset for all 10 endoscopic instrument types. The mean average accuracy, precision, recall, and F1-score were 99.1%, 92.0%, 88.8%, and 89.3%, respectively. The area under the curve values exceeded 0.94 for all instrument types. Heatmaps of endoscopic procedures were generated for both retrospective and real-time analyses. CONCLUSIONS: We successfully developed an automated endoscopic video analysis system, EndoAdd, which supports retrospective assessment and real-time monitoring. It can be used for data analysis and quality control of endoscopic procedures in clinical practice.

A scoring system to predict the technical difficulty of endoscopic resection for cardial submucosal tumors.

BACKGROUND AND AIM: Endoscopic resection has been successfully used for the removal of digestive submucosal tumors (SMTs). However, the cardia has been considered a challenging location for endoscopic resection due to its narrow lumen and sharp angle. The objective of this study was to establish a clinical scoring model to grade the technical difficulty of endoscopic resection for cardial SMTs. METHODS: A total of 246 patients who suffered cardial SMTs and received endoscopic resection were included in this retrospective study. All of them were randomized into the training cohort (n = 123) or internal validation cohort (n = 123). Potential predictors were analyzed using univariate analysis. Then, covariates with P < 0.05 were selected for the multivariate logistic regression model. The ß coefficients from the logistic regression model were used to create a scoring system for technical difficulty prediction by rounding the score to the nearest integer of the absolute ß coefficient value. RESULTS: The clinical score consisted of the following factors: male gender (2 points), extraluminal growth (3 points), and maximum diameter ≥3 cm (3 points). The scoring model demonstrated good discriminatory power, with an area under the receiver operating characteristic curve of 0.860 and a 95% confidence interval of 0.763-0.958. The model also showed a good goodness of fit in the Hosmer-Lemeshow test (P = 0.979). In the training cohort, the probability of encountering technical difficulty in the easy (score = 0), intermediate (score = 1-3), difficult (score = 4-6), and very difficult (score >6) categories was 0, 6.8%, 33.3%, and 100.0%, respectively; similarly, in the validation cohort, it was 0, 5.6%, 22.2%, and 50.0%, respectively. CONCLUSIONS: This scoring system could serve as a valuable tool for clinicians in predicting the technical difficulty of endoscopic resection for cardial SMTs.

Long-term outcomes of endoscopic resection for well-differentiated nonampullary duodenal neuroendocrine tumors.

BACKGROUND AND AIMS: Nonampullary duodenal neuroendocrine tumors (NAD-NETs) are rare, with limited evidence regarding endoscopic treatment. This study investigated the efficacy and safety of endoscopic resection of well-differentiated NAD-NETs and evaluated long-term outcomes, including local recurrence and metastasis. METHODS: Seventy-eight patients with NAD-NETs who underwent endoscopic resection between January 2011 and August 2022 were included. Clinicopathologic characteristics and treatment outcomes were collected and analyzed. RESULTS: En-bloc resection was achieved for 74 tumors (94.9%) and R0 resection for 68 tumors (87.2%). Univariate analysis identified tumors in the second part of the duodenum, tumor size ≥10 mm, and muscularis propria invasion as risk factors for noncurative resection. Two patients with R1 resection (vertical margin involvement) and 2 patients with lymphovascular invasion underwent additional surgery. Four patients experienced adverse events (5.1%), including 2 cases of delayed bleeding and 2 cases of perforation, all successfully managed conservatively. During a median follow-up period of 62.6 months, recurrence and lymph node metastasis were only detected in 1 patient with R1 resection 3 months after the original procedure. CONCLUSIONS: Endoscopic resection is safe and effective and provides a favorable long-term outcome for patients with well-differentiated NAD-NETs without regional lymph node or distant metastasis.

Endoscopic resection for calcifying fibrous tumors of the gastrointestinal tract.

BACKGROUND: Calcifying fibrous tumors (CFTs) are rare mesenchymal lesions that can occur in various sites throughout the body, including the tubular gastrointestinal (GI) tract. AIM: To analyze the clinical findings of 36 patients with GI tract CFTs to provide guidance for diagnosis and treatment. METHODS: This retrospective study included 36 patients diagnosed with CFTs of the GI tract. We collected demographic and clinical information and conducted regular follow-ups to assess for local recurrence. RESULTS: The stomach was the most commonly involved site, accounting for 72.2% of the 36 CFTs. Endoscopic mucosal resection (n = 1, 2.8%), endoscopic submucosal dissection (n = 14, 38.9%), endoscopic full-thickness resection (n = 16, 44.4%), and submucosal tunneling endoscopic resection (n = 5, 13.9%) were used to resect calcifying fibrous tumors. Overall, 34 (94.4%) CFTs underwent complete endoscopic resections with a mean procedure time of 39.8 ± 29.8 min. The average maximum diameter of the tumors was 10.6 ± 4.3 cm. No complications, such as bleeding or perforation, occurred during an average hospital stay of 2.9 ± 1.2 d. In addition, two patients developed new growth of CFTs near the primary tumor sites, and none of the patients developed distant metastases during the follow-up period. CONCLUSION: GI tract CFTs are rare and typically benign tumors that can be effectively managed with endoscopic procedures.

Endoscopic features and treatments of gastric cystica profunda.

BACKGROUND: Gastric cystica profunda (GCP) represents a rare condition characterized by cystic dilation of gastric glands within the mucosal and/or submucosal layers. GCP is often linked to, or may progress into, early gastric cancer (EGC). AIM: To provide a comprehensive evaluation of the endoscopic features of GCP while assessing the efficacy of endoscopic treatment, thereby offering guidance for diagnosis and treatment. METHODS: This retrospective study involved 104 patients with GCP who underwent endoscopic resection. Alongside demographic and clinical data, regular patient follow-ups were conducted to assess local recurrence. RESULTS: Among the 104 patients diagnosed with GCP who underwent endoscopic resection, 12.5% had a history of previous gastric procedures. The primary site predominantly affected was the cardia (38.5%, n = 40). GCP commonly exhibited intraluminal growth (99%), regular presentation (74.0%), and ulcerative mucosa (61.5%). The leading endoscopic feature was the mucosal lesion type (59.6%, n = 62). The average maximum diameter was 20.9 ± 15.3 mm, with mucosal involvement in 60.6% (n = 63). Procedures lasted 73.9 ± 57.5 min, achieving complete resection in 91.3% (n = 95). Recurrence (4.8%) was managed via either surgical intervention (n = 1) or through endoscopic resection (n = 4). Final pathology confirmed that 59.6% of GCP cases were associated with EGC. Univariate analysis indicated that elderly males were more susceptible to GCP associated with EGC. Conversely, multivariate analysis identified lesion morphology and endoscopic features as significant risk factors. Survival analysis demonstrated no statistically significant difference in recurrence between GCP with and without EGC (P = 0.72). CONCLUSION: The findings suggested that endoscopic resection might serve as an effective and minimally invasive treatment for GCP with or without EGC.

Endoscopic resection of giant esophageal subepithelial lesions: experience from a large tertiary center.

BACKGROUND AND AIMS: Increased reports on endoscopic resection (ER) of esophageal giant subepithelial lesions (g-SELs) have emerged in recent years. The aim of this study was to evaluate the efficacy, technical difficulty, and safety through our single-center experience. METHODS: Seventy-five patients with g-SELs undergoing endoscopic resection were included in the training set. Clinicopathologic features, procedure-related characteristics, postprocedural outcomes, and follow-up data were analyzed. A predictive nomogram model for procedural difficulty was proposed based on the multivariable logistic regression analysis. Internal and external validations were conducted to verify the model performance. RESULTS: The overall en bloc resection rate was 93.3%. Intraoperative and postoperative adverse events occurred in 7 (9.3%) and 13 (17.3%) patients, respectively. No recurrence or metastasis was observed. Thirty-two (42.7%) patients underwent a difficult procedure. Age (adjusted odds ratio [aOR], .915; P = .004), maximal tumor diameter ≥8 cm (aOR, 9.896; P = .009), irregular shape (aOR, 4.081; P = .053), extraluminal growth pattern (aOR, 5.419; P = .011), and submucosal tunneling endoscopic resection (aOR, .109; P = .042) were found to be statistically or clinically significant factors for predicting endoscopic resection difficulty, based on which a nomogram model was developed. Internal and external validations of the nomogram via receiver-operating characteristic curves and calibration curves achieved favorable results. CONCLUSIONS: Endoscopic resection serves as a promising therapeutic option for esophageal g-SELs. A younger patient age, large tumor size, irregular shape, and extraluminal growth may indicate increased endoscopic resection difficulty, whereas a submucosal tunneling endoscopic resection procedure tends to be of lower difficulty. Our nomogram model performs well for predicting endoscopic resection difficulty for esophageal g-SELs.

Feasibility and safety of endoscopic resection for the jejunoileal lesions.

BACKGROUND: Endoscopic resection (ER) for jejunoileal lesions (JILs) has been technically challenging. We aimed to characterize the clinicopathologic characteristics, feasibility, and safety of ER for JILs. METHOD: We retrospectively investigated 52 patients with JILs who underwent ER from January 2012 to February 2022. We collected and analyzed clinicopathological characteristics, procedure-related parameters, outcomes, and follow-up data. RESULTS: The mean age was 49.4 years. Of the 52 JILs, 33 ileal tumors within 20 cm from the ileocecal valve were resected with colonoscopy, while 19 tumors in the jejunum or the ileum over 20 cm from the ileocecal valve received enteroscopy resection. The mean procedure duration was 49.0 min. The en bloc resection and en bloc with R0 resection rates were 86.5% and 84.6%, respectively. Adverse events (AEs) included one (1.9%) major AE (delayed bleeding) and five (9.6%) minor AEs. During a median follow-up of 36.5 months, two patients had local recurrence (3.8%), while none had metastases. The 5-year recurrence-free survival (RFS) and disease-specific survival (DSS) were 92.9% and 94.1%, respectively. Compared with the enteroscopy group, overall AEs were significantly lower in the colonoscopy group (P < 0.05), but no statistical differences were observed in RFS (P = 0.412) and DSS (P = 0.579). There were no significant differences in AEs, RFS, and DSS between the endoscopic submucosal dissection (ESD) and the endoscopic mucosal resection (EMR) group. CONCLUSIONS: ER of JILs has favorable short-term and long-term outcomes. Both ESD and EMR can safely and effectively resect JILs in appropriately selected cases.

Endoscopic management of duodenal perforation caused by foreign bodies in adults: A retrospective study.

BACKGROUND AND AIMS: Duodenal perforation caused by foreign bodies (FBs) is very rare but is an urgent emergency that traditionally requires surgical intervention. Several case reports have reported the successful endoscopic removal of duodenal perforating FBs. Here we aimed to evaluate the safety and efficacy of endoscopic management of duodenal perforating FBs in adults. METHODS: Between October 2004 and October 2022, 12,851 patients with endoscopically diagnosed gastrointestinal FBs from four tertiary hospitals in China were retrospectively reviewed. Patients were enrolled if they were endoscopically and/or radiographically diagnosed with duodenal perforating FBs. RESULTS: The incidence of duodenal total FBs and perforating FBs was 1.9% and 0.3%, respectively. Thirty-four patients were enrolled. Endoscopic removal was achieved in 25 patients (73.5%), and nine patients (26.5%) received surgery. For the endoscopic group, most perforating FBs were located in the duodenal bulb (36.0%) and descending part (28.0%). The adverse events included 3 mucosal injuries and 1 localized peritonitis. All patients were cured after conventional treatment. In the surgical group, most FBs were lodged in the descending part (55.6%). One patient developed localized peritonitis and one patient died of multiple organ failure. The significant features of FBs requiring surgery included FB over 10 cm, both sides perforation, multiple perforating FBs and massive pus overflow. CONCLUSION: Endoscopic removal of duodenal perforating FBs is safe and effective, and can be the first choice of treatment for experienced endoscopists. Surgical intervention may be required for patients with FBs over 10 cm, both sides perforation, multiple perforating FBs, or severe infections.

Markov modeling and performance analysis of infectious diseases with asymptomatic patients.

After over three years of COVID-19, it has become clear that infectious diseases are difficult to eradicate, and humans remain vulnerable under their influence in a long period. The presence of presymptomatic and asymptomatic patients is a significant obstacle to preventing and eliminating infectious diseases. However, the long-term transmission of infectious diseases involving asymptomatic patients still remains unclear. To address this issue, this paper develops a novel Markov process for infectious diseases with asymptomatic patients by means of a continuous-time level-dependent quasi-birth-and-death (QBD) process. The model accurately captures the transmission of infectious diseases by specifying several key parameters (or factors). To analyze the role of asymptomatic and symptomatic patients in the infectious disease transmission process, a simple sufficient condition for the stability of the Markov process of infectious diseases is derived using the mean drift technique. Then, the stationary probability vector of the QBD process is obtained by using RG-factorizations. A method of using the stationary probability vector is provided to obtain important performance measures of the model. Finally, some numerical experiments are presented to demonstrate the model's feasibility through analyzing COVID-19 as an example. The impact of key parameters on the system performance evaluation and the infectious disease transmission process are analyzed. The methodology and results of this paper can provide theoretical and technical support for the scientific control of the long-term transmission of infectious diseases, and we believe that they can serve as a foundation for developing more general models of infectious disease transmission.

Risk factors for complications and incomplete resection after endoscopic resection for duodenal submucosal tumors.

BACKGROUND AND AIM: Endoscopic resection (ER) has been used to remove submucosal tumors (SMTs) in recent years; however, duodenal ER is associated with high rates of immediate or delayed bleeding and perforation. Whether ER can be recommended for the treatment of duodenal SMTs remains controversial. Therefore, we aimed to investigate the clinical outcomes associated with the ER of duodenal SMTs and to assess possible predictive factors for complications and incomplete resection. METHODS: This retrospective study included 141 patients with duodenal SMTs. The therapeutic outcomes from ER and procedure-related complications were analyzed. RESULTS: Of the 141 patients, 78.7% achieved complete resection and nine (6.4%) developed complications. The multivariate analysis suggested that location near the duodenal papilla (P = 0.010) and diameter exceeding 15 mm (P = 0.091) of duodenal SMTs were independent risk factors for complications in ER. Besides, submucosal fibrosis (P = 0.042), location near the duodenal papilla (P = 0.049), and irregular morphology (P = 0.067) were independent risk factors for incomplete resection. CONCLUSIONS: ER can be recommended as an effective and minimally invasive treatment for duodenal SMTs.

Management of delayed bleeding of upper gastrointestinal endoscopic submucosal tunneling procedures: a retrospective single-center analysis and brief meta-analysis.

OBJECTIVES: Delayed bleeding is a rare but important major adverse event (mAE) after endoscopic submucosal tunneling procedures (ESTP), which is scarcely reported. We aimed to characterize the clinical characteristics of delayed bleeding and provide better management of this mAE. METHOD: From August 2010 to October 2022, we reviewed 3852 patients with achalasia receiving peroral endoscopic myotomy (POEM) and 1937 patients with upper gastrointestinal tumors receiving submucosal tunneling endoscopic resection (STER). Among these, records of 22 patients (15 POEM, 7 STER) with delayed bleeding were collected. Clinical characteristics, treatment, and outcomes of delayed bleeding were analyzed. RESULTS: The mean age was 43.6 years. Ten patients (45.5%) were intratunnel bleeding, seven (31.8%) were intratunnel bleeding accompanied by mucosal bleeding, and five (22.7%) were mucosal bleeding. The most common accompanied symptoms were hematemesis, fever, and melena. The most common accompanied mAEs were fistula, pulmonary inflammation, and pleural effusion with atelectasis. The mean duration from ESTP to endoscopic intervention was 5.3 ± 4.9 days. Active bleeding was identified in 21 patients (95.5%). The bleeding was successfully controlled by electrocoagulation (19 cases), endoscopic clipping (six cases), and Sengstaken-Blakemore tube insertion (three cases), and no patient required surgical intervention. The mean hemostatic procedure duration was 61.8 ± 45.8 min. The mean post-bleeding hospital stay was 10.0 ± 6.2 days. A brief meta-analysis of previous studies showed the pooled estimate delayed bleeding rate after POEM, STER, and G-POEM was 0.4%. CONCLUSIONS: Delayed bleeding is uncommon and could be effectively managed by timely emergency endoscopic procedures without requiring subsequent surgical interventions.

The role of type II esophageal microbiota in achalasia: Activation of macrophages and degeneration of myenteric neurons.

OBJECTIVE: The gut microbiota plays a critical role in the appropriate development and maintenance of the enteric nervous system (ENS). Esophageal achalasia (EA) is a rare motility disorder characterized by the selective degeneration of inhibitory neurons in the esophageal myenteric plexus. This study aimed to evaluate the composition of the esophageal microbiota in achalasia and explore the potential microbial mechanisms involved in its pathogenesis. DESIGN: The lower esophageal mucosal microbiota was analyzed in patients with achalasia and control participants using 16 S rRNA sequencing. The association between the esophageal microbiota and achalasia was validated by inducing esophageal dysbiosis in C57BL/10 J and C57BL/10ScNJ (TLR4KO) mice via chronic exposure to ampicillin sodium in their drinking water. RESULTS: The esophageal microbiota in EA patients had lower diversity and a predominance of Gram-negative bacteria (Type II microbiota) compared to that in the healthy controls. Additionally, the relative abundance of Rhodobacter decreased significantly in patients with achalasia, which correlated with an enrichment of lipopolysaccharide (LPS) biosynthesis based on the COG database. Antibiotic-treated mice showed an esophageal microbiota characterized by increased abundance of Gram-negative bacteria (Type II microbiome), decreased abundance of Rhodobacter, and enriched LPS biosynthesis. Compared to the control and TLR4KO mice, the antibiotic-treated wild-type mice had higher LES resting pressure, increased LES contraction rate after carbachol stimulation, and decreased relaxation response to L-arginine. Moreover, the number of myenteric neurons decreased, while the number of lamina propria macrophages (LpMs) increased after antibiotic exposure. Furthermore, the TLR4-MYD88-NF-κB pathway was up-regulated, and the production of TNF-α, IL-1ß, and IL-6 increased in the antibiotic-treated mice. CONCLUSIONS: Patients with achalasia exhibit esophageal dysbiosis, which may induce aberrant esophageal motility.

A single-cell transcriptional landscape of immune cells shows disease-specific changes of T cell and macrophage populations in human achalasia.

Achalasia is a rare motility disorder of the esophagus caused by the gradual degeneration of myenteric neurons. Immune-mediated ganglionitis has been proposed to underlie the loss of myenteric neurons. Here, we measure the immune cell transcriptional profile of paired lower esophageal sphincter (LES) tissue and blood samples in achalasia and controls using single-cell RNA sequencing (scRNA-seq). In achalasia, we identify a pattern of expanded immune cells and a specific transcriptional phenotype, especially in LES tissue. We show C1QC+ macrophages and tissue-resident memory T cells (TRM), especially ZNF683+ CD8+ TRM and XCL1+ CD4+ TRM, are significantly expanded and localized surrounding the myenteric plexus in the LES tissue of achalasia. C1QC+ macrophages are transcriptionally similar to microglia of the central nervous system and have a neurodegenerative dysfunctional phenotype in achalasia. TRM also expresses transcripts of dysregulated immune responses in achalasia. Moreover, inflammation increases with disease progression since immune cells are more activated in type I compared with type II achalasia. Thus, we profile the immune cell transcriptional landscape and identify C1QC+ macrophages and TRM as disease-associated immune cell subsets in achalasia.

Landscape of Psychological Profiles in Patients With Esophageal Achalasia.

INTRODUCTION: Esophageal achalasia (EA) is a chronic esophageal dysmotility disease, of which psychological distress was poorly understood. This study aims to assess the status of psychosocial characteristics in EA and to determine the relationship between psychological distress and EA. METHODS: Seventy pairs of age and gender-matched patients with EA and healthy control individuals were prospectively enrolled from December 2019 to April 2020 at our hospital. Demographic, psychosocial, and clinical data were obtained. Psychosocial assessments contained psychological distress (Symptom Checklist-90 Revised), perceived stress (Perceived Stress Scale-14), and stressful life events (Life Events Scale). Comparison for psychological parameters was made between patients with EA and controls as well as for EA before/after per oral endoscopic myotomy (POEM). Spearman rank correlation coefficients were used to testify the association between psychological distress and achalasia symptoms. RESULTS: The mean course and Eckardt score of patients with EA were 4.26 ± 5.11 years and 6.63 ± 2.21, respectively. There was a significant difference between patients with EA and healthy individuals in Global Severity Index ( P = 0.039) and Positive Symptoms Total ( P = 0.041) for Symptom Checklist-90 Revised as well as positive intensity ( P = 0.011) for the Life Events Scale. Somatization ( P < 0.001), anxiety ( P = 0.021), anger-hostility ( P = 0.009), and others (appetite and sleep, P = 0.010) accounted for the most difference. Somatization was positively associated with chest pain ( P = 0.045). Two patients with EA developed recurrence and showed no relationship with psychological status. Psychological status was significantly improved after POEM. DISCUSSION: Psychological distress, especially somatization, was more prevalent in patients with EA than healthy controls. POEM seemed able to improve psychological distress.

Endoscopic resection and suturing methods for non-ampullary duodenal submucosal tumors: "mini-invasive" treatments that should never be underestimated.

OBJECTIVE: To evaluate the effectiveness and safety of endoscopic resection and various suturing methods to treat non-ampullary duodenal submucosal tumors (NAD-SMTs). DESIGN: We performed a retrospective observational study of patients with NAD-SMTs who underwent endoscopic resection at Zhongshan Hospital, Fudan University, China, between June 2017 and December 2020. Data on patient characteristics, treatments and follow-up results were collected. The association between clinicopathologic characteristics and different suturing methods or adverse events were analyzed. RESULTS: Of 128 patients analyzed, 26 underwent endoscopic mucosal resection (EMR), 64 underwent endoscopic submucosal excavation (ESE), and 38 underwent endoscopic full-thickness resection (EFTR). EMR and ESR are both appropriate for non-full-thickness lesions, whereas ESE is more appropriate for tumors located in the bulb or descending duodenum. Gastric tube drainage is more strongly recommended after ESE. Satisfactory suturing is also vital endoscopic resection of NAD-SMTs. Metallic clips are often used in EMR or ESE of non-full-thickness lesions. The pathological findings revealed that the full-thickness lesions were predominantly gastrointestinal stromal tumors (GIST), Brunner's tumor or lipoma, and the surgeons usually used purse-string sutures to close the wounds. The operation time was longer for purse-string suture closure than metallic clip closure. Eleven patients had complications. Risk factors for adverse events included large-diameter tumor (≥ 2 cm), location in the descending part of the duodenum, involvement of the fourth layer of the duodenal wall, EFTR, and GIST. CONCLUSIONS: Endoscopic resection of NAD-SMTs is effective but is associated with a high incidence of complications due to their anatomical peculiarities. Preoperative diagnosis is quite important. Careful selection of treatment and suturing methods are necessary to reduce the risk of adverse effects. Given the increased frequency of severe complications during or following duodenal endoscopic resection, this procedure should be performed by experienced endoscopists.

Salvage peroral endoscopic myotomy is a promising treatment for achalasia after myotomy failure.

BACKGROUND AND AIMS: Reintervention modalities after myotomy failure in achalasia patients have yet to be established. The efficacy and safety of salvage peroral endoscopic myotomy (POEM) for treatment of achalasia after myotomy failure were evaluated in the study. METHODS: Between August 2011 and August 2021 at the Endoscopy Center of Zhongshan Hospital, 219 achalasia patients who had previously undergone a myotomy underwent a salvage POEM and were thus retrospectively enrolled in this study. After propensity score matching (PSM), operation-related parameters were compared between the salvage POEM group and the naïve POEM group. Subgroup analysis was performed between patients with previous Heller myotomy (HM) and patients with previous POEM. RESULTS: With similar baseline characteristics between both groups after PSM, the salvage POEM group presented with shorter tunnel length (11.8 ± 2.2 cm vs 12.8 ± .9 cm, P < .0001) and myotomy length (9.8 ± 2.0 cm vs 10.4 ± 1.0 cm, P < .0001) than the naïve POEM group. No significant differences were found in procedure-related adverse events between patients of salvage POEM and naïve POEM. The primary outcome of treatment success occurred in 175 of 193 patients (90.7%) in the salvage POEM group versus 362 of 374 patients (96.8%) in the naïve POEM group (P = .0046). At a 2- and 5-year follow-up, significantly higher rates of clinical failures were observed in the previous HM subgroup than in the previous POEM subgroup (P = .0433 and P = .0230, respectively). CONCLUSIONS: Salvage POEM after a previous myotomy failure, especially after a POEM failure, is a promising treatment option because it has a durable clinical relief rate.