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.

Deep learning analysis for differential diagnosis and risk classification of gastrointestinal tumors.

OBJECTIVES: Recently, artificial intelligence (AI) has been applied to clinical diagnosis. Although AI has already been developed for gastrointestinal (GI) tract endoscopy, few studies have applied AI to endoscopic ultrasound (EUS) images. In this study, we used a computer-assisted diagnosis (CAD) system with deep learning analysis of EUS images (EUS-CAD) and assessed its ability to differentiate GI stromal tumors (GISTs) from other mesenchymal tumors and their risk classification performance. MATERIALS AND METHODS: A total of 101 pathologically confirmed cases of subepithelial lesions (SELs) arising from the muscularis propria layer, including 69 GISTs, 17 leiomyomas and 15 schwannomas, were examined. A total of 3283 EUS images were used for training and five-fold-cross-validation, and 827 images were independently tested for diagnosing GISTs. For the risk classification of 69 GISTs, including very-low-, low-, intermediate- and high-risk GISTs, 2,784 EUS images were used for training and three-fold-cross-validation. RESULTS: For the differential diagnostic performance of GIST among all SELs, the accuracy, sensitivity, specificity and area under the receiver operating characteristic (ROC) curve were 80.4%, 82.9%, 75.3% and 0.865, respectively, whereas those for intermediate- and high-risk GISTs were 71.8%, 70.2%, 72.0% and 0.771, respectively. CONCLUSIONS: The EUS-CAD system showed a good diagnostic yield in differentiating GISTs from other mesenchymal tumors and successfully demonstrated the GIST risk classification feasibility. This system can determine whether treatment is necessary based on EUS imaging alone without the need for additional invasive examinations.

Endoscopic resection for non-ampullary duodenal subepithelial lesions: a retrospective cohort study.

PURPOSE: This study aimed to assess the safety and efficacy of endoscopic submucosal dissection (ESD) and pre-cutting endoscopic mucosal resection (pEMR) in treating non-ampullary duodenal subepithelial lesions (NADSELs) and to evaluate the clinical utility of endoscopic ultrasound (EUS) before endoscopic resection (ER). METHODS: In this retrospective single-centre cohort study, we compared the clinical outcomes of patients with NADSELs who underwent ESD or pEMR between January 2014 and June 2023. The accuracies of EUS in determining the pathological type and origin of the lesions were evaluated using postoperative histopathology as the gold standard. RESULTS: Overall, 56 patients with NADSELs underwent ER in this study, including 16 and 40 treated with pEMR and ESD, respectively. There were no significant differences between the two groups in terms of en bloc resection rate, complete (R0) resection rate, perioperative complication rate, and postoperative hospital length of stay (P > 0.05). However, the pEMR group had significantly shorter median operational (13.0 min vs. 30.5 min, P < 0.001) and mean fasting (1.9 days vs. 2.8 days, P = 0.006) time and lower median hospital costs (¥12,388 vs. ¥19,579, P = 0.002). The accuracies of EUS in determining the pathological type and origin of the lesions were 76.8% and 94.6%, respectively, compared with histopathological evaluation. CONCLUSIONS: EUS can accurately predict the origin of NADSELs. Suitable lesions determined to originate from the submucosa or more superficial layers using EUS can be treated using pEMR as it shortens the operational and recovery time, reduces hospitalisation costs, and achieves an R0 resection rate similar to ESD.

Endoscopic submucosal resection (ESD) and endoscopic full-thickness resection (EFTR) via balloon-assisted enteroscopy (BAE) in small bowel subepithelial lesions: experience in treating fifteen cases.

AIM: The study objective was to evaluate the primary feasibility of endoscopic submucosal resection (ESD) and endoscopic full-thickness resection (EFTR) via balloon-assisted enteroscopy (BAE) to treat small bowel subepithelial lesions (SELs). METHOD: A retrospective case series study was performed. The first fifteen consecutive patients who underwent ESD (n = 10) and EFTR (n = 5) via BAE to remove small bowel SELs from November 2016 to December 2023 were included. The main outcome measures were the technique success rate, operative time and complication rate. RESULTS: This research focused on 15 cases of jejunoileal SELs, four cases of lipomyoma, three cases of ectopic pancreas, two cases of NETs, three cases of benign fibrous tumours and three cases of angioma. The overall technique success rate was 86.7%, with 100% (10/10) and 60% (3/5) for BAE-ESD and BAE-EFTR, respectively, in removing small bowel SELs. Two cases of EFTR failed, as the BAE operation was unsuitable for tumour resection and suture repair of a perforated wound. No serious bleeding or any postoperative complications occurred. The median time of endoscopic resection via BAE for SELs was 44 min (range 22-68 min). CONCLUSION: ESD and EFTR via BAE might be alternative choices for treating small SELs in the small bowel, with the advantages of clear and accurate positioning and minimal invasiveness. However, its superiority over surgery still needs to be further investigated.

Gastric lymphangioma: a case report and review of literature.

BACKGROUND: Gastric lymphangioma is one of the highly rare benign tumors characterized by multilocular or unilocular lymphatic spaces. Herein, we report a case of lymphangioma in the gastric antrum. CASE PRESENTATION: A 77-year-old male patient who had been experiencing epigastric discomfort for a year was presented to our hospital. A gastric subepithelial lesion was diagnosed by upper endoscopy and was entirely excised via diatal subtotal gastrectomy. Endoscopic ultrasonography revealed an echoless homogenous echo pattern in the third wall layer. A lymphangioma was diagnosed by pathologic investigation of the resected specimen. The PubMed, Embase and Web of Science databases were reviewed for literature in English while using the keywords of "gastric lymphangioma" or "lymphangioma of stomach" or "gastric lymphatic cyst" or "lymphatic cyst of stomach" and the results were discussed. CONCLUSION: Gastric lymphangioma is a rarely occurring submucosal tumor that should be considered when diagnosing subepithelial lesions in the stomach.

Endoscopic submucosal dissection for proximal duodenal subepithelial lesions: a retrospective cohort study.

BACKGROUND AND AIM: Endoscopic submucosal dissection (ESD) has been used to remove subepithelial lesions (SELs) in recent years; however, duodenal ESD is associated with high rates of immediate or delayed bleeding and perforation. Whether ESD can be recommended for the treatment of duodenal SELs remains controversial. Therefore, we evaluated the efficacy and safety of ESD for duodenal SELs. METHODS: We conducted a retrospective cohort study in 62 patients (62 lesions) who underwent ESD for duodenal SELs between January 2012 and December 2020. The therapeutic outcomes from ESD for duodenal SELs and procedure-related complications were analyzed. RESULTS: En bloc resection and complete resection rates associated with duodenal ESD were 90.3% and 100%, respectively; four patients had a positive microscopic margin on pathologic examination. The median procedure time was 45 min (range 20-106 min). During the procedure, two patients received emergency surgery for uncontrolled bleeding and perforation, respectively. After the procedure, delayed bleeding occurred in three patients (4.8%), which was successfully managed by clipping, and delayed perforation occurred in two patients (3.2%) and needed emergency surgery. Risk factors related to complications were analyzed. Lesion size was found to be significantly associated with the complications (P = 0.028). No recurrences were detected, and no distant metastasis was observed in any patient during a median follow-up period of 45.5 months (range, 6-103 months). CONCLUSION: Duodenal ESD is relatively safe and feasible for duodenal SELs, especially for lesions no more than 2 cm in size.

Novel endoscopic ultrasonography imaging technique for visualizing microcirculation without contrast enhancement in subepithelial lesions: Prospective study.

OBJECTIVES: Detective flow imaging for endoscopic ultrasonography (DFI?EUS) is a new imaging modality developed for detecting fine vessels without using ultrasound contrast agents. This study aimed to evaluate its utility by comparing it with a type of directional power Doppler (eFLOW) for subepithelial lesions (SELs). METHODS: Between January 2019 and January 2020, 28 patients with SELs undergoing DFI?EUS and eFLOW?EUS were enrolled. DFI?EUS and eFLOW?EUS assessing the vascularity in SELs were compared in terms of the rates of identification of intratumoral vessels. We also investigated how large vessels were depicted in both modalities based on surgical specimens as well as the detection rates of intratumoral vessels in gastrointestinal stromal tumors (GISTs) and non?GISTs using either DFI?EUS or eFLOW?EUS. RESULTS: Among 28 patients, 23 with pathological confirmation by EUS?guided fine?needle aspiration biopsy (EUS?FNAB) specimens were included. Of those 23 patients, the 10 who underwent surgical resection were selected for analysis. The rate of detection of intratumoral vessels in SELs was significantly higher on DFI?EUS (80%) than on eFLOW?EUS (30%) (P\xA0=\xA00.03). Comparison with surgical specimens revealed that detection rate for vessels with maximum size of less 1000\xA0µm was higher in DFI?EUS (66%) than that in eFLOW?EUS (0%). GIST patients had significantly higher positive rates (90%) of intratumoral vessels than non?GIST patients (31%) on DFI in 23 cases including EUS?FNAB specimens (P\xA0=\xA00.045). CONCLUSIONS: Detective flow imaging?EUS is more sensitive for depicting intratumoral vessels than eFLOW?EUS. Evaluation of intratumoral vessels on DFI?EUS is useful for identifying GISTs without contrast agents.

Risk factors for complications of therapeutic endoscopy for upper gastrointestinal subepithelial lesions. / ä¸Šæ¶ˆåŒ–é“ä¸Šçš®ä¸‹ç— å˜è¡Œå† é•œæ²»ç–—åŽå¹¶å‘ç—‡çš„å±é™©å› ç´ .

OBJECTIVES: To study the risk factors for complications after endoscopic therapy for upper gastrointestinal subepithelial lesions (SELs). METHODS: Retrospective analysis was performed on 184 patients in the Department of Gastroenterology in the Third Xiangya Hospital, Central South University after therapeutic endoscopy [endoscopic submucosal dissection (ESD), endoscopic full-thickness resection (EFR), endoscopic submucosal excavation (ESE), and submucosal tunneling endoscopic resection (STER)] for the upper gastrointestinal SELs from 2014-09-01 to 2019-09-30. The clinic data were collected and risk factors for postoperative complications were analyzed. RESULTS: Among the 184 patients, 22 patients were in the complication group (including 3 cases of delayed bleeding, 2 cases of delayed perforation, and 17 cases of electrocoagulation syndrome) and 162 patients were in the non-complication group. There was no significant difference between the complication group and the non-complication group in gender, age over 70 year, basic diseases, lesion location, lesion invasion layers, pathological results, endoscopic therapy, and preventive closure of wounds (all P>0.05). The differences between the two groups in lesion diameter over 40 mm, operative time over 120 minutes, and rate of intraoperative perforation were significant (all P<0.05). Logistic regression analysis showed that lesion diameter over 40 mm and operative time over 120 minutes were independent risk factors for postoperative complications. CONCLUSIONS: For the patients with upper gastrointestinal SELs after endoscopic minimally invasive therapy with the lesion diameter over 40 mm and the operative time over 120 minutes, it needs to highly alert to the occurrence of postoperative complications.

In vivo real-time diagnosis of endoscopic ultrasound-guided needle-based confocal laser endomicroscopy in gastric subepithelial lesions.

BACKGROUND AND AIM: The effect of real-time analysis of needle-based confocal laser endomicroscopy (nCLE) for gastric subepithelial lesions (SELs) on the diagnostic value is unclear. The study aimed to investigate the diagnostic efficacy of real-time nCLE for gastric SELs and to assess the technical aspects and safety of real-time nCLE. METHODS: Consecutive patients with gastric SELs ≥ 1 cm were prospectively investigated by endoscopic ultrasound (EUS), followed by nCLE. During EUS-nCLE, real-time nCLE diagnosis was made by an expert endoscopist. The procedure-relative adverse events were assessed and recorded. One-month washout period later, nCLE videos were reviewed off-line by the same endoscopist. The nCLE diagnoses were compared with corresponding pathological results. Additionally, image quality and interobserver agreements for the criteria were evaluated by three experienced endomicroscopists. RESULTS: Except for one failing to be punctured, 60 patients completed EUS-nCLE procedures successfully. Real-time nCLE had high diagnostic accuracies of ≥ 88.3% for gastric SELs. There were no significant differences between real-time and off-line nCLE diagnoses for gastric SELs (P > 0.05). The overall accuracy of real-time nCLE for diagnosis of gastric SELs was 86.7%. There were no procedure-relative adverse events occurred. In addition, the mean image quality score was 3.6 (1 = poor and 5 = excellent). The interobserver agreement was "almost perfect" for ectopic pancreas and "substantial" for gastrointestinal stromal tumor, leiomyoma, and carcinoma. CONCLUSIONS: Endoscopic ultrasound-nCLE could provide in vivo real-time diagnostic imaging with a high diagnostic accuracy. Meanwhile, real-time nCLE was feasible and had a satisfactory safety profile.

Endoscopic Full Thickness Resection.

Recent advances in minimally invasive endoscopic approaches have pushed the boundaries of well-established resection techniques for therapeutic and diagnostic applications. Endoscopic full thickness resection techniques are a key development in the management of challenging epithelial and subepithelial lesions that are not amenable to conventional endoscopic resection methods and previously required a surgical approach. Endoscopic full thickness biopsy represents a paradigm shift in tissue acquisition and will enhance our understanding of the pathophysiology, and guide therapy, of gastrointestinal neuromuscular diseases, as well as other inflammatory and neoplastic conditions. This review highlights current tools and techniques available for endoscopic full thickness resection and biopsy, as well as outcomes from such interventions.

Rectal Endoscopic Ultrasound in Clinical Practice.

PURPOSE OF REVIEW: Endoscopic ultrasound (EUS) is routinely utilized for evaluation of disorders of the lower gastrointestinal tract. In this review, we summarize the current status of rectal EUS in clinical practice and describe recent developments in diagnostic and therapeutic rectal EUS. RECENT FINDINGS: Recent guidelines recommend rectal EUS for rectal cancer staging as a second line modality in cases where MRI is contraindicated. Forward-viewing echoendoscopes and through the scope EUS miniprobes allow for EUS imaging of lesions through the entire colon and for evaluation beyond stenoses or luminal narrowings. EUS can be used to assess perianal disease and drain pelvic abscess associated with IBD, along with newer applications currently under investigation. For rectal varices, EUS can confirm the diagnosis, assess the optimal site for banding, guide therapy placement with sclerotherapy and/or coils, and assess response to treatment by confirming absence of flow. Therapeutic rectal EUS is emerging as a promising modality for drainage of pelvic fluid collection drainage and fiducial placement for rectal or prostatic cancer. Drug delivery mechanisms and substances that may increase the scope of therapy with rectal EUS are in varying stages of development. Rectal EUS continues to be an important modality for evaluation of benign and malignant disorders of the lower gastrointestinal tract, although its use as a cancer staging modality has declined due to improvements in MRI technology. Various technologies to enhance ultrasound imaging and for therapeutics have been developed that have or may contribute to expanded indications for rectal EUS.

A case of gastric carcinoma with lymphoid stroma diagnosed by an endoscopic ultrasound-guided fine-needle biopsy.

Endoscopic ultrasound-guided sampling is indicated to achieve an accurate diagnosis of subepithelial lesions of the stomach when a standard biopsy fails. Gastric carcinoma with lymphoid stroma (GCLS) is located under the epithelial layer with dense lymphocytic infiltration, making a pathological diagnosis by a biopsy difficult. We herein report a case of the pathological diagnosis of GCLS using an endoscopic ultrasound-guided fine-needle biopsy. The patient underwent distal gastrectomy and was diagnosed with Epstein-Barr virus-negative cancer.

Clinical course of asymptomatic duodenal subepithelial lesions.

BACKGROUND/AIMS: There is limited knowledge regarding the management of duodenal subepithelial lesions (SELs) owing to a lack of understanding of their natural course. This study aimed to assess the natural course of asymptomatic duodenal SELs and provide management recommendations. METHODS: Patients diagnosed with duodenal SELs and followed up for a minimum of 6 months were retrospectively investigated. RESULTS: Among the 443,533 patients who underwent esophagogastroduodenoscopy between 2008 and 2020, duodenal SELs were identified in 0.39% (1,713 patients). Among them, 396 duodenal SELs were monitored for a median period of 72.5 months (interquartile range, 37.7-111.3 mo). Of them, 16 SELs (4.0%) showed substantial changes in size or morphology at a median follow-up of 35.1 months (interquartile range, 21.7-51.4 mo). Of these SELs with substantial changes, tissues of two SELs were acquired using endoscopic ultrasound-guided fine needle aspiration biopsy: one was a lipoma and the other was non-diagnostic. Three SELs were surgically or endoscopically removed; two were diagnosed as gastrointestinal stromal tumors, and one was a lipoma. An initial size of 20 mm or larger was associated with substantial changes during follow-up (p = 0.016). CONCLUSION: While the majority of duodenal SELs may not exhibit substantial interval changes, regular follow-up with endoscopy may be necessary for cases with an initial size of 20 mm or larger, considering a possibility of malignancy.

Combining Endoscopic Submucosa Dissection and Endoscopic Full-Thickness Resection for Resection of a Gastric Schwannoma Mimicking Gastrointestinal Stroma Tumor.

Subepithelial gastric tumors are a diagnostic challenge. Endoscopic ultrasound allows differentiation. Lesions originating from the submucosal layer can be resected using endoscopic submucosal dissection (ESD). Surgery or endoscopic full-thickness resection (EFTR) techniques are alternatives. We present a patient with an 11 × 8 mm submucosal tumor in the gastric antrum suggestive of a gastrointestinal stromal tumor, originating from the muscularis propria. Eventually endoscopic resection was performed, combining ESD and EFTR (hybrid ESD-EFTR). Contrary to expectations, histology revealed a gastric schwannoma. This case illustrates an efficient and safe endoscopic hybrid technique for the removal of submucosal gastric lesions.

Ligation-assisted endoscopic submucosal resection following unroofing technique for small esophageal subepithelial lesions originating from the muscularis propria.

BACKGROUND: The majority of esophageal subepithelial lesions originating from the muscularis propria (SEL-MPs) are benign in nature, although a subset may exhibit malignant characteristics. Conventional endoscopic resection techniques are time-consuming and lack efficacy for small SEL-MPs. AIM: To evaluate the efficacy and safety of ligation-assisted endoscopic submucosal resection (ESMR-L) following unroofing technique for small esophageal SEL-MPs. METHODS: From January 2021 to September 2023, 17 patients diagnosed with esophageal SEL-MPs underwent ESMR-L following unroofing technique at the endoscopy center of Shenzhen People's Hospital. Details of clinicopathological characteristics and clinical outcomes were collected and analyzed. RESULTS: The mean age of the patients was 50.12 ± 12.65 years. The mean size of the tumors was 7.47 ± 2.83 mm and all cases achieved en bloc resection successfully. The average operation time was 12.2 minutes without any complications. Histopathology identified 2 Lesions (11.8%) as gastrointestinal stromal tumors at very low risk, 12 Lesions (70.6%) as leiomyoma and 3 Lesions (17.6%) as smooth muscle proliferation. No recurrence was found during the mean follow-up duration of 14.18 ± 9.62 months. CONCLUSION: ESMR-L following roofing technique is an effective and safe technique for management of esophageal SEL-MPs smaller than 20 mm, but it cannot ensure en bloc resection and may require further treatment.

Efficacy of real-time artificial intelligence-aid endoscopic ultrasonography diagnostic system in discriminating gastrointestinal stromal tumors and leiomyomas: a multicenter diagnostic study.

Background: Gastrointestinal stromal tumors (GISTs) represent the most prevalent type of subepithelial lesions (SELs) with malignant potential. Current imaging tools struggle to differentiate GISTs from leiomyomas. This study aimed to create and assess a real-time artificial intelligence (AI) system using endoscopic ultrasonography (EUS) images to differentiate between GISTs and leiomyomas. Methods: The AI system underwent development and evaluation using EUS images from 5 endoscopic centers in China between January 2020 and August 2023. EUS images of 1101 participants with SELs were retrospectively collected for AI system development. A cohort of 241 participants with SELs was recruited for external AI system evaluation. Another cohort of 59 participants with SELs was prospectively enrolled to assess the real-time clinical application of the AI system. The AI system's performance was compared to that of endoscopists. This study is registered with Chictr.org.cn, Number ChiCT2000035787. Findings: The AI system displayed an area under the curve (AUC) of 0.948 (95% CI: 0.921-0.969) for discriminating GISTs and leiomyomas. The AI system's accuracy (ACC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) reached 91.7% (95% CI 87.5%-94.6%), 90.3% (95% CI 83.4%-94.5%), 93.0% (95% CI 87.2%-96.3%), 91.9% (95% CI 85.3%-95.7%), and 91.5% (95% CI 85.5%-95.2%), respectively. Moreover, the AI system exhibited excellent performance in diagnosing ≤20 mm SELs (ACC 93.5%, 95% CI 0.900-0.969). In a prospective real-time clinical application trial, the AI system achieved an AUC of 0.865 (95% CI 0.764-0.966) and 0.864 (95% CI 0.762-0.966) for GISTs and leiomyomas diagnosis, respectively, markedly surpassing endoscopists [AUC 0.698 (95% CI 0.562-0.834) for GISTs and AUC 0.695 (95% CI 0.546-0.825) for leiomyomas]. Interpretation: We successfully developed a real-time AI-assisted EUS diagnostic system. The incorporation of the real-time AI system during EUS examinations can assist endoscopists in rapidly and accurately differentiating various types of SELs in clinical practice, facilitating improved diagnostic and therapeutic decision-making. Funding: Science and Technology Commission Foundation of Shanghai Municipality, Science and Technology Commission Foundation of the Xuhui District, the Interdisciplinary Program of Shanghai Jiao Tong University and the Research Funds of Shanghai Sixth people's Hospital.

Traction-Assisted Endoscopic Submucosal Dissection of a Gastric Subepithelial Tumor: A Case Report.

Endoscopic submucosal dissection (ESD) is considered curative for patients with early gastrointestinal cancers. However, it is a technically challenging procedure that can be time-consuming and associated with complications such as bleeding and perforation. Traction devices and techniques have been developed to mitigate these risks and reduce procedure times. Most traction devices are unavailable in New Zealand, and traction techniques have not been widely utilized due to the precision required for successful outcomes. We report the first case of traction-assisted ESD performed in New Zealand for a gastric submucosal tumor. The procedure was successfully performed using the clip with rubber band traction technique. The lesion was resected en bloc, and histology confirmed an R0, curative resection. There were no complications, and the total procedure time was 54 minutes. In conclusion, traction techniques can be effectively employed for ESD in lesions with difficult submucosal access. They contribute to safer dissections and reduced procedure times.

Endoscopic resection in subepithelial lesions of the upper gastrointestinal tract: Experience at a tertiary referral hospital in The Netherlands.

Background and study aims Histological confirmation of subepithelial lesions (SELs) in the upper gastrointestinal tract remains challenging. Endoscopic resection of SELs is increasingly used for its excellent diagnostic yield and opportunity to do away with continued surveillance. In this study, we aimed to evaluate the indications, success rates and complications of different endoscopic resection techniques for SELs at a large, tertiary referral hospital in Rotterdam, The Netherlands. Patients and methods Data between October 2013 and December 2021 were retrospectively collected and analyzed. Main outcomes were R0-resection rate, en bloc resection rate, recurrence rate, and procedure-related adverse events (AEs) (Clavien-Dindo). Secondary outcomes were procedure time, need for surgical intervention, and clinical impact on patient management. Results A total of 58 patients were referred for endoscopic resection of upper gastrointestinal SELs. The median diameter of lesions was 20 mm (range 7-100 mm). Median follow-up time was 5 months (range 0.4-75.7). Forty-eight procedures (83%) were completed successfully leading to en bloc resection in 85% and R0-resection in 63%. Procedure-related AEs occurred in six patients (13%). Severe complications (CD grade 3a) were seen in three patients. The local recurrence rate for (pre)malignant diagnosis was 2%. Additional surgical intervention was needed in seven patients (15%). A total of 32 patients (67%) could be discharged from further surveillance after endoscopic resection. Conclusions Endoscopic resection is a safe and effective treatment for SELs and offers valuable information about undetermined SELs for which repeated sampling attempts have failed to provide adequate tissue for diagnosis.

Endoscopic ultrasound artificial intelligence-assisted for prediction of gastrointestinal stromal tumors diagnosis: A systematic review and meta-analysis.

BACKGROUND: Subepithelial lesions (SELs) are gastrointestinal tumors with heterogeneous malignant potential. Endoscopic ultrasonography (EUS) is the leading method for evaluation, but without histopathological analysis, precise differentiation of SEL risk is limited. Artificial intelligence (AI) is a promising aid for the diagnosis of gastrointestinal lesions in the absence of histopathology. AIM: To determine the diagnostic accuracy of AI-assisted EUS in diagnosing SELs, especially lesions originating from the muscularis propria layer. METHODS: Electronic databases including PubMed, EMBASE, and Cochrane Library were searched. Patients of any sex and > 18 years, with SELs assessed by EUS AI-assisted, with previous histopathological diagnosis, and presented sufficient data values which were extracted to construct a 2 × 2 table. The reference standard was histopathology. The primary outcome was the accuracy of AI for gastrointestinal stromal tumor (GIST). Secondary outcomes were AI-assisted EUS diagnosis for GIST vs gastrointestinal leiomyoma (GIL), the diagnostic performance of experienced endoscopists for GIST, and GIST vs GIL. Pooled sensitivity, specificity, positive, and negative predictive values were calculated. The corresponding summary receiver operating characteristic curve and post-test probability were also analyzed. RESULTS: Eight retrospective studies with a total of 2355 patients and 44154 images were included in this meta-analysis. The AI-assisted EUS for GIST diagnosis showed a sensitivity of 92% [95% confidence interval (CI): 0.89-0.95; P < 0.01), specificity of 80% (95%CI: 0.75-0.85; P < 0.01), and area under the curve (AUC) of 0.949. For diagnosis of GIST vs GIL by AI-assisted EUS, specificity was 90% (95%CI: 0.88-0.95; P = 0.02) and AUC of 0.966. The experienced endoscopists' values were sensitivity of 72% (95%CI: 0.67-0.76; P < 0.01), specificity of 70% (95%CI: 0.64-0.76; P < 0.01), and AUC of 0.777 for GIST. Evaluating GIST vs GIL, the experts achieved a sensitivity of 73% (95%CI: 0.65-0.80; P < 0.01) and an AUC of 0.819. CONCLUSION: AI-assisted EUS has high diagnostic accuracy for fourth-layer SELs, especially for GIST, demonstrating superiority compared to experienced endoscopists' and improving their diagnostic performance in the absence of invasive procedures.