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.

Endoscopic Treatment of Complex Walled-Off Necrosis in Necrotizing Pancreatitis With Two Simultaneous Lumen-Apposing Metal Stents: A Case Report.

Organized pancreatic and peripancreatic collections are complications of pancreatitis and should be treated when symptomatic or complicated. When feasible, the endoscopic ultrasound approach presents high efficacy and low morbidity and mortality, making it the first likely option. Among the available accessories for endoscopic drainage, the lumen-apposing metal stent can be a better option, with a low migration rate; furthermore, it allows endoscopic necrosectomy. Here, we present the case of complex walled-off necrosis treated with two lumen-apposing metal stents in the same procedure. A 41-year-old male patient with walled-off necrosis presented with delayed gastric emptying and obstruction of the main biliary duct. Magnetic resonance imaging and endoscopic ultrasound revealed two non-communicating collections. We opted for endoscopic ultrasound-guided drainage with the deployment of two simultaneous lumen-apposing metal stents: one transduodenal and the other transgastric, with clinical improvement. After three weeks, endoscopic retrograde cholangiopancreatography showed a biliary fistula communicating with the periduodenal collection, which was treated with a biliary plastic stent. An endoscopic necrosectomy was performed, and the metal stents were removed. Control magnetic resonance imaging demonstrated improvement. The patient was asymptomatic at the six-month follow-up. The treatment of symptomatic complex walled-off necrosis remains a challenge and may require multiple endoscopic approaches; moreover, surgical treatment may be necessary in case of failure. In the present report, we demonstrate that the deployment of two lumen-apposing metal stents in the same procedure is feasible when necessary as it was associated with technical success and short-term clinical success.