Establishment of Standards for the Referral of Large Non-Pedunculated Colorectal Polyps: An International Expert Consensus Using a Modified Delphi Process.

BACKGROUND AND AIMS: Resection of colorectal polyps has been shown to decrease the incidence and mortality of colorectal cancer. Large non-pedunculated colorectal polyps are often referred to expert centres for endoscopic resection, which requires relevant information to be conveyed to the therapeutic endoscopist to allow for triage and planning of resection technique. The primary objective of our study was to establish minimum expected standards for the referral of LNPCP for potential ER. METHODS: A Delphi methodology was employed to establish consensus on minimum expected standards for the referral of large colorectal polyps among a panel of international endoscopy experts. The expert panel was recruited through purposive sampling, and three rounds of surveys were conducted to achieve consensus, with quantitative and qualitative data analysed for each round. RESULTS: A total of 24 international experts from diverse continents participated in the Delphi study, resulting in consensus on 19 statements related to the referral of large colorectal polyps. The identified factors, including patient demographics, relevant medications, lesion factors, photodocumentation and the presence of a tattoo, were deemed important for conveying the necessary information to therapeutic endoscopists. The mean scores for the statements ranged from 7.04 to 9.29 out of 10, with high percentages of experts considering most statements as a very high priority. Subgroup analysis by continent revealed some variations in consensus rates among experts from different regions. CONCLUSION: The identified consensus statements can aid in improving the triage and planning of resection techniques for large colorectal polyps, ultimately contributing to the reduction of colorectal cancer incidence and mortality.

Clinical outcomes of anti-reflux mucosal ablation for gastroesophageal reflux disease: An international bi-institutional study.

BACKGROUND AND AIM: Anti-reflux mucosal ablation (ARMA) is an emerging endoscopic treatment aimed at enhancing the gastroesophageal junction flap valve. This study aimed to evaluate its feasibility, effectiveness, and safety. METHODS: Between May 2018 and December 2022, patients with gastroesophageal reflux disease (GERD) symptoms refractory to acid suppression medications or those dependent on such medications were enrolled for ARMA. This retrospective analysis utilized prospectively collected data from an international bi-center study. GERD questionnaire, upper endoscopy, and 24-h pH monitoring were conducted at 2-6 months and 12 months post-ARMA. Clinical success was defined as a > 50% reduction in a validated GERD questionnaire. RESULTS: A total of 68 patients underwent ARMA. Definitive GERD was diagnosed in 44 (64.7%) patients, while 24 (35.3%) exhibited reflux hypersensitivity. Clinical success rates at 2-6 months and 1 year post-ARMA were 60% (39/65) and 70% (21/30), respectively. The median GERD-health-related quality of life score significantly improved from 26 to 11 at 2-6 months (P < 0.001). Among the 51 patients (71.8%) who underwent 24-h pH monitoring, the median acid exposure time decreased from 5.3% to 0.7% (P = 0.003), accompanied by a significant reduction in esophagitis rates (P < 0.001). Multivariate analysis did not identify predictors of short-term success. Nine (13.2%) patients experienced transient stenosis requiring balloon dilation. CONCLUSIONS: ARMA demonstrates both technical feasibility and reproducibility as a safe procedure that effectively ameliorates GERD symptoms in approximately two-thirds of patients during short-term follow up. Both reflux hypersensitivity and confirmed GERD patients, regardless of their response to acid suppression medication, may be suitable candidates.

Radiation proctitis after iodine-125 low-dose-rate prostate brachytherapy utilizing SpaceOAR hydrogel.

OBJECTIVE: We retrospectively evaluated the efficacy of combining the SpaceOAR (SOAR) hydrogel with prostate brachytherapy, using colonoscopy findings to assess for radiation proctitis. METHODS: Among 731 patients undergoing iodine-125 low-dose-rate prostate brachytherapy (LDR-BT), SOAR was utilized in 394 patients (53.9%). Colonoscopy was performed for 97 patients (13.3%) to assess the presence, location, condition, and treatment of radiation proctitis. We also investigated treatment factors associated with the occurrence of radiation proctitis. RESULTS: Radiation proctitis was observed in 57 patients (7.8%) and 17 (2.3%) were treated with argon plasma coagulation (APC). The incidence of radiation proctitis was 12.2% in the non-SOAR and 4.1% in the SOAR group (p < 0.001). In the non-SOAR group, the incidence of radiation proctitis was 6.6% for LDR-BT monotherapy and increased to 22.0% when combined with external beam radiation therapy (EBRT) (p = 0.001). However, in the SOAR group, these rates significantly decreased to 3.3% and 5.7% for monotherapy and combination therapy, respectively (p = 0.035, p < 0.001). With SOAR, inflammation was observed directly above the DL in most patients (87.5%), and only one patient (6.3%) required APC. The absence of SOAR (p < 0.001, HR = 0.29) and the concurrent use of EBRT (p = 0.018, HR = 2.87) were identified as significant risk factors for the occurrence of radiation proctitis. CONCLUSION: The use of SOAR significantly reduced the incidence of radiation proctitis in patients undergoing LDR-BT monotherapy and combined EBRT. Inflammation primarily occurred directly above the DL; further examination is necessary to clarify its cause.

Long-term efficacy of antireflux mucosectomy in patients with refractory gastroesophageal reflux disease.

OBJECTIVES: Minimally invasive treatments have been applied for gastroesophageal reflux disease (GERD), but the long-term results are controversial. Antireflux mucosectomy (ARMS) is a simple endoscopic procedure that does not require the insertion of a foreign body. We provide the first report on the long-term results of ARMS. METHODS: This was a single-center, single-arm trial, prospective study of 88 patients with proton pump inhibitor (PPI)-refractory GERD who underwent ARMS between June 2012 and June 2017. Primary outcomes were the rates of long-term effectiveness and PPI discontinuation. Secondary outcomes were to compare patients' preoperative background characteristics, questionnaire, and multichannel intraluminal impedance and pH monitoring data to examine the predictive factors of ARMS. The clinical course was reviewed, including the need for additional treatment after ARMS. RESULTS: Antireflux mucosectomy produced a long-term effect in 68.3% of the patients, and PPI could be discontinued in 42% of patients. There were significant differences in age, intensity of preoperative symptoms, and acid-related indicators. Forty-five percent (27/60) had reflux hypersensitivity and ARMS provided long-term effectiveness in 81% of these patients. There was no significant difference in subjective symptom assessment between those with short-term and long-term efficacy. Additional treatment was administered in 23% (14/60) and scheduled at 1-2 years' follow-up. CONCLUSIONS: Antireflux mucosectomy showed long-term efficacy, and many of the cases with short-term effects were able to maintain them. In addition, ARMS is also effective in patients with reflux hypersensitivity, and provides a treatment option that bridges the gap between surgical and medical treatment.

Feasibility and safety of per-oral endoscopic septotomy for Killian-Jamieson diverticulum: Case series with video.

BACKGROUND AND AIMS: Killian-Jamieson diverticulum (KJD) is a relatively uncommon variant of pharyngoesophageal diverticula, distinct from the more prevalent Zenker diverticulum. However, literature on endoscopic management of KJD remains limited. This study aimed to elucidate the efficacy and safety of peroral endoscopic septotomy (POES) as a treatment approach for symptomatic KJD. METHODS: In this retrospective observational study, we investigated the outcomes of nine consecutive patients who underwent POES for KJD between January 2019 and May 2023. Follow-up data of at least 2 months post-treatment were analyzed. The primary outcome measure was the technical success rate of POES. Secondary outcomes encompassed the clinical success rate, defined as symptomatic improvement 2 months after POES, and the incidence of adverse events. RESULTS: All patients presented with dysphagia, with a median symptom duration of 6 months (interquartile range [IQR]: 3-12 months). The median diverticulum size was 32 mm (IQR: 24-42 mm). The median duration of the operation time was 66 min (IQR: 60-109). A 100% technical success rate was achieved, with complete closure of the defect in all cases. There were no adverse events related to this treatment. The median hospitalization duration was 5 days (IQR: 4-6), and the clinical success rate was 88.9%. Follow-up barium esophagograms exhibited significant improvement in the flow of the barium for all patients. CONCLUSIONS: Despite the relatively limited case volume, our findings underscore that POES is a safe and efficacious approach for managing symptomatic KJD.

Learning curve for peroral endoscopic myotomy in therapeutic endoscopy experts and nonexperts: Large single-center experience.

OBJECTIVES: Reports on learning curve for peroral endoscopic myotomy (POEM) in therapeutic endoscopy nonexperts are limited. We aimed to assess the number of cases required to achieve POEM proficiency for endoscopic submucosal dissection (ESD) experts and nonexperts. METHODS: This is a retrospective study at the largest POEM referral center in Japan. POEM between April 2014 and December 2020 were included. Nonexperts and ESD experts were divided by training phases: A, 1-20; B, 21-40; C, 41-60; D, 61-80; and E, 81-100 cases. Primary outcome was operation time, and the phase to reach target time (83 min) was investigated. Secondary outcomes were clinical success rate, adverse events, and post-POEM gastroesophageal reflux disease (GERD). RESULTS: Five hundred and sixty-six cases were performed by 14 nonexperts, and 555 cases by 15 ESD experts. As the primary outcome, operation time in nonexperts was: A, 95 (79-115.8); B, 86.5 (71-105); C, 80 (70-100); D, 73 (64.5-100.5); and E, 73.5 (57.8-88.8) min, while in ESD experts: A, 90 (74-128); B, 77 (70-92); and C, 77 (70-93.5) min (median [interquartile range]). Operation time decreased significantly as experience increased in both groups (P < 0.001), and nonexperts required 41-60 cases to achieve proficiency, while experts required 21-40 cases. As secondary outcomes, in nonexperts, clinical success was 96.9-100%, adverse events were 5.0-9.2%, symptomatic GERD was 11.8-26.5%, and proton pump inhibitor (PPI) intake was 11.5-18.7% in each phase. While in experts, clinical success was 96.2-100%, adverse events were 3.0-5.8%, symptomatic GERD was 14.6-22.0%, and PPI intake was 12.6-17.9%. There were no significant differences among training phases. CONCLUSIONS: Non-ESD experts require more cases to achieve proficiency in POEM. These results are useful for establishing POEM training programs and institutional implementation of the procedure.

Pilot study on anti-reflux mucoplasty: Advancing endoscopic anti-reflux therapy for gastroesophageal reflux disease.

OBJECTIVES: Anti-reflux mucosectomy (ARMS) and anti-reflux mucosal ablation (ARMA) were developed as interventions for proton pump inhibitor (PPI)-refractory/-dependent gastroesophageal reflux disease (GERD). Although ARMS and ARMA are established treatments for PPI-refractory GERD, reliance on natural healing for ulcer scar formation introduces uncertainty and bleeding risk. To address these issues, we introduced a novel approach called anti-reflux mucoplasty (ARM-P), which involves immediate closure of mucosal defects following mucosectomy. This pilot study aims to evaluate the safety, feasibility, and efficacy of ARM-P. METHODS: A retrospective single-center study was conducted using prospectively collected data from October 2022 to July 2023. Patients with PPI-refractory/-dependent GERD who underwent ARM-P were included. The study evaluated technical success of ARM-P, before and after ARM-P GERD-Health Related Quality of Life Questionnaire, GerdQ, and Frequency Scale for the Symptoms of GERD scores, along with PPI discontinuation and endoscopic esophagogastric junction morphology. RESULTS: A total of 20 patients with a median age of 61.5 years underwent the ARM-P procedure. The procedure achieved 100% technical success without adverse events. After ARM-P, 55.0% discontinued PPI usage and 15.0% reduced PPI dose by half. Median GERD-Health Related Quality of Life Questionnaire score improved from 21 to 6 (P = 0.0026), median GerdQ score improved from 9 to 7 (P = 0.0022), and median Frequency Scale for the Symptoms of GERD score decreased from 16 to 7 (P = 0.0003). Median Hill's Classification significantly improved from grade III to grade I (P = 0.0001). CONCLUSIONS: This study presents the first pilot report of ARM-P, demonstrating its procedural safety, technical feasibility, and short-term efficacy.

Endoscopic pressure study integrated system for the diagnosis of achalasia.

OBJECTIVES: The endoscopic pressure study integrated system (EPSIS) is a novel diagnostic tool used to evaluate lower esophageal sphincter (LES) function. EPSIS allows the measurement of intragastric pressure (IGP) during gastric insufflation through esophagogastroduodenoscopy (EGD) and records its pressure waveform. This study aimed to assess the usefulness and applicability of EPSIS as an adjunct diagnostic modality for achalasia. METHODS: This case-control study was conducted using a database of patients who underwent EGD, barium swallow (BS), high-resolution manometry (HRM), and EPSIS between January 2022 and December 2022. The achalasia (experimental) group (n = 35) consisted of patients with a definitive diagnosis of achalasia. The control group (n = 34) consisted of patients with no abnormalities in EGD, BS, or HRM and no abnormal acid reflux confirmed with 24-h pH-impedance monitoring. EPSIS findings were compared between the two groups and characterized by the waveform pattern (uphill or flat), maximum IGP (IGP-Max), pressure difference, and the gradient of the waveform. RESULTS: All patients in the achalasia group showed an uphill pattern, in contrast to 21 patients (61.8%) in the control group. IGP-Max demonstrated the best diagnostic accuracy for achalasia, with a cut-off value of 15.8 mmHg (100% sensitivity, 58.8% specificity, and area under the curve [AUC] 0.78). The pressure gradient also demonstrated good diagnostic accuracy, with a cut-off value of 0.40 mmHg/s (80% sensitivity, 61.8% specificity, and AUC 0.76). CONCLUSION: This study demonstrated that EPSIS can be applied as a diagnostic modality in patients with achalasia.

A novel endoscopic purse-string suture technique, "loop 9", for gastrointestinal defect closure: a pilot study.

BACKGROUND : This study aimed to assess the feasibility and efficacy of the novel loop 9 method of gastrointestinal (GI) defect closure. METHODS : 20 patients underwent a GI procedure that required defect closure. Loop 9 can be delivered through a single instrument channel (3.2 mm) and released at the defect site. After it has been anchored by two clips positioned on opposite sides of the defect edge, the loop 9 is tightened by pulling the end of the suture intraluminally using biopsy forceps. Additional clips are placed to achieve complete closure. The primary outcome was complete closure rate. The secondary outcomes were closure time, sustained closure rate, and adverse events. RESULTS : Complete closure was achieved in 100 % of cases. The mean size of the mucosal defects was 17.5 mm (range 10-55 mm). The median closure time was 14 minutes. The sustained closure rate was 90 %. No adverse events were noted. CONCLUSIONS : The loop 9 technique is feasible and effective in achieving complete and sustained closure of therapeutic endoscopy-related GI defects.

Novel modified side-by-side balloon dilatation method for esophagogastric junction strictures: Single-/double-barrel techniques.

Endoscopic balloon dilatation is an established treatment for benign gastrointestinal strictures. In order to dilatate safely, it is necessary to dilatate gradually and preferably under direct endoscopic visualization. However, it is currently difficult to achieve dilatation widths of 20-30 mm with commercial products and of over 30-mm with endoscopic visualization. Therefore, a safe and innovative application technique is needed for patients who need these 20-mm or greater dilatation widths. We have developed two methods that enable more than 20-mm dilatation under direct visualization. (i) Single-barrel method: an endoscopic balloon dilatation catheter was fixed with grasping forceps at the tip of the endoscope and carried into the stomach. The balloon catheter was released from the endoscope to create a retroflexed view. The endoscope and balloon were positioned adjacent to each other at the gastric cardia. The balloon was inflated gradually and the esophagogastric junction was dilatated under direct visualization. (ii) Double-barrel method: the same procedure was repeated with two balloons. Theoretically, we achieved a dilatation of >30-mm in diameter. These modified methods may be helpful for esophagogastric junction strictures, such as esophageal achalasia (serving as an initial endoscopic balloon dilatation prior to using a 30-mm achalasia balloon), or for functional strictures after Nissen fundoplication. In conclusion, our simple, modified method enables safe and gradual dilatation under direct endoscopic visualization. Additionally, combination of the sizes of one or two balloons can achieve various widths of dilatation.

Simplified endoscopic pressure study integrated system for the diagnosis of gastroesophageal reflux disease.

Endoscopic pressure study integrated system (EPSIS) is a novel tool for the diagnosis of gastroesophageal reflux disease. It enables the evaluation of the function of the lower esophageal sphincter by monitoring intragastric pressure (IGP) while insufflating the stomach during esophagogastroduodenoscopy. EPSIS can predict abnormal acid reflux with high accuracy based on previous studies. IGP was measured by inserting through the working channel of the scope an intragastric catheter connected to a pressure measuring device. Herein, we assess the feasibility of an updated EPSIS system, which can be performed just by connecting a flush tube to the working channel. This method does not require inserting foreign objects in the stomach and spares catheter insertion in order to simplify the procedure and reduce costs. A single-center pilot study was conducted to evaluate the association between catheter-based EPSIS and the updated EPSIS. The results of EPSIS in 20 patients who underwent both methods were assessed. In all cases, the waveform pattern of IGP measured by catheter-based EPSIS and updated EPSIS was consistent with 15 uphill pattern and five flat pattern. Intraobserver agreement of waveform pattern was perfect between two examiners with kappa value = 1. Intraclass correlation coefficient (ICC) for intraobserver reliability for maximum IGP was excellent with 0.91 (95% confidence interval [CI] of 0.77 < ICC < 0.96) and for pressure gradient was also good with 0.89 (95% CI of 0.71 < ICC < 0.95). In conclusion, our study suggests that the updated EPSIS can be performed without the use of a catheter.

Diagnostic yield of fourth-generation endocytoscopy for esophageal squamous lesions using a modified endocytoscopic classification.

OBJECTIVES: Endocytoscopy (EC) is an ultra-high magnification endoscopy designed to provide in vivo histologic assessment. This study aimed to evaluate the diagnostic yield of the newly developed fourth-generation EC for esophageal squamous lesions by using a modified EC classification. METHODS: A total of 2548 EC images of 57 esophageal targeted areas between June 2015 and October 2017 were retrospectively collected. Two lesions with low-quality images were excluded. Only EC images were independently reviewed by two expert and two non-expert endoscopists. The lesions were classified according to a three-tier modified EC classification. We used a multilevel logistic regression to analyze the data. RESULTS: The sensitivity and specificity of diagnosing non-squamous cell cancer (SCC) vs SCC were 82.5% and 83.0% by the experts; 90.1% and 75.0% by non-experts. The interobserver agreement among the four raters was good (kappa statistic 0.59). The diagnostic accuracy of experts and non-experts was similar (P = 0.16 for specificity and P = 0.20 for sensitivity). The sensitivity and specificity of EC for non-neoplasia vs neoplasia were 88.7% and 74.6% by experts; 90.3 and 52.1% by non-experts. The interobserver agreement among the four raters was moderate (kappa statistic 0.44). The specificity of experts was higher compared to non-experts, although the difference did not reach statistical significance (P = 0.08 for specificity and P = 0.93 for sensitivity). CONCLUSIONS: Fourth-generation EC offers acceptable diagnostic accuracy and reliability in both experts and non-experts, especially when diagnosing SCC lesions.

Importance of second-look endoscopy after per-oral endoscopic myotomy for safe postoperative management.

OBJECTIVES: Per-oral endoscopic myotomy (POEM) is a safe and effective treatment for achalasia and esophageal motility disorders. The role of second-look endoscopy (SE) on postoperative day 1 has not been examined. This study aimed to evaluate the findings and need of SE after POEM. METHODS: This is a single-center, retrospective study. All consecutive patients who underwent POEM and SE on postoperative day 1 between December 2017 and September 2019 were included. The primary endpoint was the rate of newly-detected adverse events (nAE) during SE that required endoscopic intervention or deviation from the normal postoperative course. Multivariate logistic regression was used to identify predictors of nAE. RESULTS: Four-hundred-ninety-seven patients (mean age, 50.3 years; female, 49.9%) were included. SE identified abnormal findings in a total of 71 patients (14.3%). nAE which required endoscopic intervention or deviation from the normal postoperative course were identified in 12 patients (2.4%): eight (1.6%) entry site dehiscence; two (0.4%) submucosal hemorrhage or hematoma; and two (0.4%) dehiscence of an intraoperative perforation site after endoclip closure. Other findings such as mucosal thermal damage without perforation and small submucosal hematoma were found in 54 patients (10.9%) and five patients (1.0%), respectively. Multivariate analysis showed that longer operation time and intraoperative adverse events (AE) were associated with clinically significant nAE during SE. CONCLUSIONS: Second-look endoscopy can detect and treat nAE that may lead to severe AE. Thus, SE should be highly considered before starting oral ingestion in all cases, and especially in those who present an intraoperative AE and longer operation time.

Characterization of intragastric pressure waveform in endoscopic pressure study integrated system: Novel diagnostic device for gastroesophageal reflux disease.

OBJECTIVES: Endoscopic pressure study integrated system (EPSIS) is a novel diagnostic tool for gastroesophageal reflux disease (GERD). EPSIS has been developed to evaluate lower esophageal sphincter function by monitoring the intragastric pressure (IGP) while insufflating the stomach during gastroscopy. Based on previous data, EPSIS could diagnose GERD with good accuracy by assessing IGP waveform pattern. This study aimed to further characterize the waveform to improve the diagnostic yield of EPSIS. METHODS: We conducted a retrospective analysis of patients with typical GERD symptoms who underwent both EPSIS and 24-h impedance-pH monitoring (MII-pH) at a single tertiary referral center from October 2018 to May 2020. EPSIS was performed by using a through-the-scope catheter connected to the pressure measuring system (TR-W550, TR-TeH08, AP-C35; Keyence, Osaka, Japan) to monitor IGP. Abnormal acid reflux was defined as acid exposure time (AET) over 6.0%. Pressure waveform was characterized as follows: (i) Basal IGP, (ii) Maximum IGP, (iii) Pressure difference, (iv) Gradient of the waveform. RESULTS: A total of 57 patients with GERD symptoms were analyzed. Twenty-one patients presented abnormal AET on MII-pH. Among EPSIS parameters, pressure difference during insufflation correlated with AET (ρ = -0.66, P < 0.01) and showed the best diagnostic accuracy for AET with the cutoff value of 4.7 mmHg (area under the curve [AUC], 0.87). The gradient of EPSIS waveform also revealed good diagnostic accuracy for abnormal AET with the cutoff value of 0.07 mmHg/s (AUC, 0.81). CONCLUSIONS: Endoscopic pressure study integrated system waveform parameters, especially pressure difference, presented high diagnostic accuracy for the presence of abnormal acid reflux.

Endoscopic pressure study integrated system reflects gastroesophageal junction competence in patients with erosive esophagitis and Barrett´s esophagus.

OBJECTIVES: The endoscopic pressure study integrated system (EPSIS) is a novel diagnostic tool for gastroesophageal reflux disease (GERD) by monitoring intragastric pressure (IGP). Evaluation of the lower esophageal sphincter (LES) function may be achieved endoscopically by utilizing this newly developed diagnostic tool. This study aimed to evaluate the association between EPSIS results and gastroesophageal reflux-related diseases, e.g., erosive esophagitis (EE) and Barrett's esophagus (BE). METHODS: This was a retrospective, single-center study. All patients who underwent EPSIS between November 2016 and July 2018 were included. EPSIS was performed during esophagogastroduodenoscopy with a dedicated electronic device and a through-the-scope catheter. The maximum IGP (IGP-max) and IGP waveform pattern (flat or uphill) were recorded with this system. Evaluation of an EE and BE was based on the Los Angeles classification and Prague classification, respectively. RESULTS: A total of 104 patients were enrolled; 29 (28%) had EE and 42 (40%) had BE. Patients with EE had lower IGP-max values (16.0 vs 18.8 mmHg, P = 0.01) and an EPSIS flat pattern was seen more frequently (82.8% vs 37.3%, P < 0.001). Similarly, patients with BE displayed a lower IGP-max (15.7 vs 19.6 mmHg, P < 0.001) and presented with an EPSIS flat pattern in a higher proportion (69% vs 37.1%, P < 0.001). These differences remained significant on multivariate analysis. CONCLUSIONS: The EPSIS, as a novel diagnostic tool, was shown to exhibit a relation with EE and BE, implying that EPSIS is a promising modality to evaluate gastroesophageal reflux-related diseases and LES function endoscopically.

Clinical outcomes of per-oral endoscopic tumor resection for submucosal tumors in the esophagus and gastric cardia.

OBJECTIVES: The clinical success of per-oral endoscopic myotomy (POEM) has led to the development of a new field of 'submucosal endoscopy'. This study aimed to evaluate the safety, efficacy, and limitations of per-oral endoscopic tumor resection (POET) in the management of submucosal tumors (SMTs) in the esophagus and the gastric cardia. METHODS: POET was performed in 47 patients from January 2011 to December 2017. The indication for POET was SMTs ≤ 30 mm in minor axis diameter. Patient and tumor characteristics (age, gender, tumor location, size, and histology), operative and clinical results of POET (procedure time and completion rate, en bloc resection rate, length of hospitalization, adverse events and tumor recurrence) were analyzed retrospectively. RESULTS: POET was successfully completed in 43 patients (91.5%) without any major adverse events (Clavien-Dindo IIIb-IV). Four patients required conversion to an open surgical procedure due to suboptimal visualization during POET. Four patients underwent piecemeal resection of their SMTs including GISTs. Median follow-up was 44 months (10-96 months), during that time, there were no incidences of tumor recurrence. Tumors that had a minor axis diameter > 30 mm or a tumor mass index (TMI) [major axis diameter (mm) × minor axis diameter (mm)] >1000 had a high likelihood of being converted to surgical resection. CONCLUSIONS: POET is a safe and effective treatment for SMTs. However, in patients where the minor axis diameter is > 30 mm or the TMI > 1000, surgical excision should be considered. Furthermore, application of POET for SMTs with malignant potential should be carefully considered to ensure optimal oncologic outcomes.

Unified Magnifying Endoscopic Classification (UMEC) of Gastrointestinal Lesions: A North American Validation Study.

Background and study aim: Magnifying endoscopy enables the diagnosis of advanced neoplasia throughout the gastrointestinal tract. The unified magnifying endoscopic classification (UMEC) framework unifies optical diagnosis criteria in the esophagus, stomach, and colon, dividing lesions into three categories: non-neoplastic, intramucosal neoplasia, and deep submucosal invasive cancer. This study aims to ascertain the performance of North American endoscopists when using the UMEC. Methods: In this retrospective cohort study, five North American endoscopists without prior training in magnifying endoscopy independently diagnosed images of gastrointestinal tract lesions using UMEC. All endoscopists were blinded to endoscopic findings and histopathological diagnosis. Using histopathology as the gold standard, the endoscopists' diagnostic performances using UMEC were evaluated. Results: A total of 299 lesions (77 esophagus, 92 stomach, and 130 colon) were assessed. For esophageal squamous cell carcinoma, the sensitivity, specificity, and accuracy ranged from 65.2% (95%CI: 50.9-77.9) to 87.0% (95%CI: 75.3-94.6), 77.4% (95%CI: 60.9-89.6) to 96.8% (95%CI: 86.8-99.8), and 75.3% to 87.0%, respectively. For gastric adenocarcinoma, the sensitivity, specificity, and accuracy ranged from 94.9% (95%CI: 85.0-99.1) to 100%, 52.9% (95%CI: 39.4-66.2) to 92.2% (95%CI: 82.7-97.5), and 73.3% to 93.3%. For colorectal adenocarcinoma, the sensitivity, specificity, and accuracy ranged from 76.2% (95%CI: 62.0-87.3) to 83.3% (95%CI: 70.3-92.5), 89.7% (95%CI: 82.1-94.9) to 97.7% (95%CI: 93.1-99.6), and 86.8% to 90.7%. Intraclass correlation coefficients indicated good to excellent reliability. Conclusion: UMEC is a simple classification that may be used to introduce endoscopists to magnifying narrow-band imaging and optical diagnosis, yielding satisfactory diagnostic accuracy.

The Journey from Endoscopic Submucosal Dissection to Third Space Endoscopy.

With the advent of endoscopic submucosal dissection, a variety of endoscopic devices including knives and high-frequency electrosurgical unit have become available. In addition, the concept of natural orifice transluminal endoscopic surgery pushed flexible endoscopic surgery ahead. In this review, the birth of peroral endoscopic myotomy and its expansion into the field of submucosal endoscopy are reviewed.

"Loop-10" line-assisted clip closure method: closure of perforation in re-do peroral endoscopic myotomy.

Video 1Demonstration of the Loop-10 closure technique for unintentional mucosal perforation during re-do esophageal peroral endoscopic myotomy.

Antireflux mucoplasty, an evolution of endoscopic antireflux therapy for refractory GERD.

Video 1We present a new therapeutic approach called antireflux mucoplasty for proton pump inhibitor-refractory GERD.