Main recommendationsESGE recommends that the evaluation of superficial gastrointestinal (GI) lesions should be made by an experienced endoscopist, using high definition white-light and chromoendoscopy (virtual or dye-based).ESGE does not recommend routine performance of endoscopic ultrasonography (EUS), computed tomography (CT), magnetic resonance imaging (MRI), or positron emission tomography (PET)-CT prior to endoscopic resection.ESGE recommends endoscopic submucosal dissection (ESD) as the treatment of choice for most superficial esophageal squamous cell and superficial gastric lesions.For Barrett’s esophagus (BE)-associated lesions, ESGE suggests the use of ESD for lesions suspicious of submucosal invasion (Paris type 0-Is, 0-IIc), for malignant lesions > 20 mm, and for lesions in scarred/fibrotic areas.ESGE does not recommend routine use of ESD for duodenal or small-bowel lesions.ESGE suggests that ESD should be considered for en bloc resection of colorectal (but particularly rectal) lesions with suspicion of limited submucosal invasion (demarcated depressed area with irregular surface pattern or a large protruding or bulky component, particularly if the lesions are larger than 20 mm) or for lesions that otherwise cannot be completely removed by snare-based techniques.ESGE recommends that an en bloc R0 resection of a superficial GI lesion with histology no more advanced than intramucosal cancer (no more than m2 in esophageal squamous cell carcinoma), well to moderately differentiated, with no lymphovascular invasion or ulceration, should be considered a very low risk (curative) resection, and no further staging procedure or treatment is generally recommended.ESGE recommends that the following should be considered to be a low risk (curative) resection and no further treatment is generally recommended: an en bloc R0 resection of a superficial GI lesion with superficial submucosal invasion (sm1), that is well to moderately differentiated, with no lymphovascular invasion, of size ≤ 20 mm for an esophageal squamous cell carcinoma or ≤ 30 mm for a stomach lesion or of any size for a BE-related or colorectal lesion, and with no lymphovascular invasion, and no budding grade 2 or 3 for colorectal lesions.ESGE recommends that, after an endoscopically complete resection, if there is a positive horizontal margin or if resection is piecemeal, but there is no submucosal invasion and no other high risk criteria are met, this should be considered a local-risk resection and endoscopic surveillance or re-treatment is recommended rather than surgery or other additional treatment.ESGE recommends that when there is a diagnosis of lymphovascular invasion, or deeper infiltration than sm1, or positive vertical margins, or undifferentiated tumor, or, for colorectal lesions, budding grade 2 or 3, this should be considered a high risk (noncurative) resection, and complete staging and strong consideration for additional treatments should be considered on an individual basis in a multidisciplinary discussion.ESGE recommends scheduled endoscopic surveillance with high definition white-light and chromoendoscopy (virtual or dye-based) with biopsies of only the suspicious areas after a curative ESD.

Background and aim: Optical diagnosis (OD) of colonic polyps is poorly reproducible outside high-volume referral centres. Present study aimed to assess whether real-time AI-assisted OD is accurate enough to implement the leave-in-situ strategy for diminutive (5mm) rectosigmoid (DRSPs) polyps. Methods: Consecutive colonoscopy outpatients with 5mm) rectosigmoid (DRSPs) polyps. Methods: Consecutive colonoscopy outpatients with >1 DRSP were included. DRSPs were categorized as adenomas or non-adenomas by the endoscopist, with different expertise in OD, with the assistance of real-time AI system (CADEYE, Fujifilm Co., Tokyo-Japan). Primary study endpoint was >90% negative predictive value (NPV) for adenomatous histology in high-confidence AI-assisted OD of DRSPs (Preservation and Incorporation of Valuable endoscopic Innovations (PIVI-1) threshold), with histopathology as reference standard. The agreement between optical- and histology-based post-polypectomy surveillance intervals (>90%, PIVI-2 threshold) was also calculated according to European Society of Gastrointestinal Endoscopy (ESGE) and United States Multi-Society Task Force (USMSTF) guidelines. Results: Overall 596 DRSPs were retrieved for histology in 389 patients; AI-assisted high-confidence OD was made in 92.3%. The NPV of AI-assisted OD for DRSPs (PIVI-1) was 91.0% (95%CI [87.1-93.9]%). PIVI-2 threshold was met in 97.4% (95%CI [95.7-98.9]%) and 92.6% (95%CI [90.0-95.2]%) of patients according to ESGE and USMSTF, respectively. The AI-assisted OD accuracy was significantly lower for non-experts (82.3%; 95% CI [76.4-87.3]%) than for experts (91.9%; 95%CI [88.5-94.5]%), however non-experts in OD quickly approached experts’ performances over time. Conclusion: AI-assisted OD matches the required PIVI thresholds. However, this does not offset the need for a high-level confidence and expertise by the endoscopist. The AI system seems to be useful especially for non-experts.

Peroral endoscopic myotomy (POEM) is an innovative, minimally invasive, endoscopic treatment for esophageal achalasia and other esophageal motility disorders, emerged from the natural orifice transluminal endoscopic surgery procedures, and since the first human case performed by Inoue in 2008, showed exciting results in international level, with more than 4000 cases globally up to now. POEM showed superior characteristics than the standard 100-year-old surgical or laparoscopic Heller myotomy (LHM), not only for all types of esophageal achalasia [classical (I), vigorous (II), spastic (III), Chicago Classification], but also for advanced sigmoid type achalasia (S1 and S2), failed LHM, or other esophageal motility disorders (diffuse esophageal spasm, nutcracker esophagus or Jackhammer esophagus). POEM starts with a mucosal incision, followed by submucosal tunnel creation crossing the esophagogastric junction (EGJ) and myotomy. Finally the mucosal entry is closed with endoscopic clip placement. POEM permitted relatively free choice of myotomy length and localization. Although it is technically demanding procedure, POEM can be performed safely and achieves very good control of dysphagia and chest pain. Gastroesophageal reflux is the most common troublesome side effect, and is well controllable with proton pump inhibitors. Furthermore, POEM opened the era of submucosal tunnel endoscopy, with many other applications. Based on the same principles with POEM, in combination with new technological developments, such as endoscopic suturing, peroral endoscopic tumor resection (POET), is safely and effectively applied for challenging submucosal esophageal, EGJ and gastric cardia tumors (submucosal tumors), emerged from muscularis propria. POET showed up to know promising results, however, it is restricted to specialized centers. The present article reviews the recent data of POEM and POET and discussed controversial issues that need further study and future perspectives.