Validation and update of a clinical score model to predict technical difficulty of colorectal endoscopic submucosal dissection: a multicenter prospective cohort study.

BACKGROUND AND AIMS: The Zhongshan colorectal endoscopic submucosal dissection (CR-ESD) score model was proposed to grade the technical difficulty of CR-ESD. The objective of this study was to prospectively validate and update the score model. METHODS: A multicenter prospective cohort analysis of CR-ESD was conducted. Individual data on patients, lesions, and outcomes of CR-ESD were used to validate the original model and further refine the difficulty of the prediction model. Data were randomly divided into discovery and internal validation cohorts. A multivariate Cox regression analysis was conducted on the discovery cohort to develop an updated risk-scoring system, which was then validated. RESULTS: Five hundred forty-eight patients with 565 colorectal lesions treated by ESD from 4 hospitals were included. In the prospective validation cohort, the area under the receiver-operating characteristic (ROC) curve for the original model was .707. Six risk factors were identified and assigned point values: tumor size (2 points for 30-50 mm, 3 points for ≥50 mm), at least two-thirds circumference of the lesion (3 points), tumor location in the cecum (2 points) or flexure (2 points), laterally spreading tumor-nongranular lesions (1 point), preceding biopsy sampling (1 point), and NBI International Colorectal Endoscopic type 3 (3 points). The updated model had an area under the ROC curve of .738 in the discovery cohort and of .782 in the validation cohort. Cases were categorized into easy (score = 0-1), intermediate (score = 2-3), difficult (score = 4-6), and very difficult (score ≥7) groups. Satisfactory discrimination and calibration were observed. CONCLUSIONS: The original model achieved an acceptable level of prediction in the prospective cohort. The updated model exhibited superior performance and can be used in place of the previous version. (Clinical trial registration number: ChiCTR2100047087.).

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.

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.

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.

Endoscopic resection of upper GI extraluminal tumors (with videos).

BACKGROUND AND AIMS: Endoscopic resection is a feasible treatment for GI extraluminal tumors but remains a challenging procedure with limited data. In this study, we assessed the safety and efficacy of endoscopic resection for extraluminal tumors in the upper GI tract. METHODS: From May 2016 to December 2021, 109 patients undergoing endoscopic resection for extraluminal tumors in the upper GI tract were retrospectively included. Clinicopathologic characteristics, procedure-related parameters, adverse events (AEs), and follow-up outcomes were analyzed. RESULTS: The en-bloc tumor resection rate was 94.5% and en-bloc retrieval rate 86.2%. Statistical analysis revealed tumor size ≥3.0 cm and irregular shape as significant risk factors for piecemeal extraction. Resection time and suture time were 46.8 ± 33.6 minutes and 20.6 ± 20.1 minutes, respectively. Large tumor size was significantly associated with a longer procedure duration. Five patients (4.6%) experienced major AEs, including recurrent laryngeal nerve injury, hydrothorax, major bleeding, local peritonitis, duodenal leakage, and repeat endoscopic surgery for tumor extraction. Minor AEs occurred in 13 patients (11.9%). Irregular tumor shape and tumor location (duodenum) were significantly associated with AE occurrence. Mean postoperative hospital stay was 4.7 ± 3.3 days. No recurrence or metastasis was observed during the mean follow-up period of 31.8 ± 15.2 months. CONCLUSIONS: Endoscopic resection is a safe and feasible therapeutic approach for upper GI extraluminal tumors. Tumor size, shape, and location impact the difficulty and safety of the procedure. Endoscopic resection of duodenal tumors is also feasible but associated with an increased risk of AEs compared with tumors in other locations.

Repeat endoscopic submucosal dissection as salvage treatment for local recurrence of esophageal squamous cell carcinoma after initial endoscopic submucosal dissection.

BACKGROUND AND AIMS: Local recurrence of esophageal squamous cell carcinoma (ESCC) after endoscopic resection does not have an established treatment. The efficacy and safety of repeat endoscopic submucosal dissection (ESD) for recurrent ESCC were determined in the study. METHODS: Forty-three consecutive patients with 45 locally recurrent superficial ESCC lesions undergoing repeat ESD and 909 first ESD lesions for propensity score matching (PSM) at Zhongshan Hospital between January 2011 and January 2020 were retrospectively enrolled. After PSM (1:2), operation-related parameters were compared between repeat ESD and first ESD. In the repeat ESD group, the Kaplan-Meier method and log-rank tests were used for identification of risk factors for local recurrence after repeat ESD. RESULTS: As compared with propensity score-matched first ESD, rates of complete resection (86.7% vs 97.8%, P = .02) and curative resection (86.7% vs 96.7%, P = .06) were lower and procedure duration (54.8 ± 21.7 minutes vs 46.2 ± 20.6 minutes, P = .67) and hospital stay (4.3 ± 1.8 days vs 2.9 ± 1.4 days, P = .25) were longer in the repeat ESD group. The en-bloc resection rate (93.3% vs 98.8%, P > .11) remained comparable. Adverse events including bleeding (4.4% vs 0%, P = .11), perforation (.0% vs .0%, P > .99), and stricture (6.7% vs 2.2%, P = .33) presented with no difference. The 5-year overall survival rate and recurrence-free survival rate for repeat ESD was 100% and 86.0%, respectively. Multiplicity was significantly associated with recurrence after repeat ESD (P = .01). CONCLUSIONS: Repeat esophageal ESD showed favorable short- and long-term outcomes and thus provides an alternative choice for recurrent superficial ESCC.

Endoscopic radial incision versus endoscopic balloon dilation as initial treatments of benign esophageal anastomotic stricture.

BACKGROUND AND AIM: We aim to evaluate the efficacy and safety of endoscopic radial incision (ERI) versus endoscopic balloon dilation (EBD) treatment of naïve, recurrent, and refractory benign esophageal anastomotic strictures. METHODS: One hundred and one ERI, 145 EBD, and 42 ERI combined with EBD sessions were performed in 136 consecutive patients with benign esophageal anastomotic stricture after esophagectomy at Zhongshan Hospital from January 2016 to August 2021. Baseline characteristics, operational procedures, and clinical outcomes data were retrospectively evaluated. Parameters and recurrence-free survival (RFS) were compared between ERI and EBD in patients with naïve or recurrent or refractory strictures. Risk factors for re-stricture after ERI were identified using univariate and multivariate analyses. RESULTS: Twenty-nine ERI versus 68 EBD sessions were performed for naïve stricture, 26 ERI versus 60 EBD for recurrent strictures, and 46 ERI versus 17 EBD for refractory stricture. With comparable baseline characteristics, RFS was greater in the ERI than the EBD group for naïve strictures (P = 0.0449). The ERI group had a lower 12-month re-stricture rate than the EBD group (37.9% vs 61.8%, P = 0.0309) and a more prolonged patency time (181.5 ± 263.1 vs 74.5 ± 82.0, P = 0.0233). Between the two interventions, recurrent and refractory strictures had similar RFS (P = 0.0598; P = 0.7668). Multivariate analysis revealed initial ERI treatment was an independent predictive factor for lower re-stricture risk after ERI intervention (odds ratio = 0.047, P = 0.001). Few adverse events were observed after ERI or EBD (3.0% vs 2.1%, P = 0.6918). CONCLUSIONS: ERI is associated with lower re-stricture rates with better patency and RFS compared with EBD for naive strictures.

Landscape of esophageal submucosal tunneling endoscopic resection-related adverse events in a standardized lexicon: a large volume of 1701 cases.

BACKGROUND: Submucosal tunneling endoscopic resection (STER) has been widely applied for esophageal submucosal tumors. This large volume study aims to provide a standard landscape of STER-related AEs for reference. METHODS: 1701 patients with esophageal SMTs undergoing STER were included at Zhongshan Hospital, Fudan University. Data of clinical characteristics and adverse events were collected and analyzed in depth. Adverse events were recorded by ASGE lexicon and graded by ASGE grading/Clavien-Dindo system. Risk factors for major AEs were analyzed by univariate and multivariate logistic regression. RESULTS: Three hundred and twenty (18.8%) patients with 962 cases of adverse events were observed. Accordingly, 84 (5.0%) were classified as major AEs (moderate and severe) by ASGE grading and 37 (2.2%) were classified as major AEs (grades III-V) by Clavien-Dindo grading. First 1 year operation, distance > 6 cm from incision to tumor, piecemeal resection, partially extraluminal location, mucosal injury, and operation time > 60 min were included in the risk score model for major AEs of STER, with 57.1% sensitivity and 87.5% specificity. CONCLUSIONS: STER was a safe procedure for diagnosis and treatment of esophageal SMTs with a total 18.8% incidence of AEs, among which only 5.0% were major AEs requiring therapeutic measurements.

Prediction of technically difficult endoscopic submucosal dissection for large superficial colorectal tumors: a novel clinical score model.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) is a promising technique for removing superficial GI tumors, but ESD is technically difficult. The aim of this study was to establish a clinical score model for grading technically difficult colorectal ESD. METHODS: Data on patients, lesions, and outcomes of colorectal ESD at 2 centers were analyzed. The objective parameter of successful ESD within 60 minutes was set as an endpoint to evaluate the difficulty. Independent predictors of difficulty in the derivation cohort were identified by multiple logistic regression analysis and used to develop a clinical score. We validated the score model in the validation cohort. RESULTS: The clinical score comprised tumor size of 30 to 50 mm (1 point) or ≥50 mm (2 points), at least two-thirds circumference of the lesion (2 points), location in the cecum (1 point), flexure (2 points) or dentate line (1 point), and laterally spreading tumor nongranular lesions (1 point). Areas under the receiver operator characteristic curves for the score model were comparable (derivation [.70] vs internal validation [.69] vs external validation [.69]). The probability of successful ESD within 60 minutes in easy (score = 0), intermediate (score = 1), difficult (score = 2-3), and very difficult (score ≥4) categories were 75.0%, 51.3%, 35.6%, and 3.4% in the derivation cohort; 73.3%, 47.9%, 31.8%, and 16.7% in the internal validation cohort; and 79.5%, 66.7%, 43.3%, and 20.0% in the external validation cohort, respectively. CONCLUSIONS: This clinical score model accurately predicts the probability of successful ESD within 60 minutes and can be applied to grade the technical difficulty before the procedure.

Controlled hypertension under hemostasis prevents post-gastric endoscopic submucosal dissection bleeding: a prospective randomized controlled trial.

BACKGROUND: Endoscopic submucosal dissection (ESD) is a prominent minimally invasive operative technique for treating early gastrointestinal tumors but can result in postoperative bleeding. We conducted a randomized controlled trial to determine whether increasing blood pressure under hemostasis during gastric ESD to identify potential bleeding spots reduces the risk of post-ESD bleeding. METHODS: In this randomized, controlled, single-blinded clinical trial, 309 patients with early gastric cancer who were admitted to a hospital to undergo ESD were recruited from March 2017 to February 2018 and were randomized into intervention and control groups. In the control group, patients underwent normal ESD. In the intervention group, we increased patients' blood pressure to 150 mmHg for 5 min using a norepinephrine pump (0.05 µg/kg/min initial dose) after the specimen was extracted during the ESD operation to identify and coagulate potential bleeding spots with hot biopsy forceps. Our primary outcome was the incidence of postoperative bleeding over 60-day follow-up. RESULTS: The incidence of post-ESD bleeding was lower in the intervention group (1.3%, 2/151) than in the control group (10.1%, 16/158, p = 0.01). Deeper tumor invasion was associated with a higher risk of post-ESD bleeding (5.3% in mucosal/submucosal layer 1 group vs. 12.5% in submucosal layer 2/muscularis propria group, p < 0.001). Multi-factor but not univariate analysis showed that proton pump inhibitor administration three times per day may be a better choice than twice per day. CONCLUSION: Increasing blood pressure under hemostasis during ESD to identify and coagulate potential bleeding spots could reduce the risk of delayed bleeding after gastric ESD.

Short- and long-term outcomes of endoscopic submucosal dissection for superficial esophageal squamous cell cancer in patients with prior gastrectomy.

BACKGROUND: The surgery for esophageal cancer arising after prior gastrectomy is technically difficult with high morbidity and mortality. Endoscopic submucosal dissection (ESD) is a minimally invasive endoscopic treatment for superficial SCC with high curative resection rate. But few studies are concerned about ESD under these circumstances. The aim of this study was to elucidate the short- and long-term outcomes of ESD for superficial esophageal squamous cell cancer (SCC) in patients with prior gastrectomy. METHODS: From January 2009 to January 2019, 37 patients with prior gastrectomy who underwent ESD for superficial esophageal SCC were retrospectively enrolled at the Zhongshan Hospital, Fudan University in Shanghai, China. Rates of en bloc resection, complete resection, curative resection, incidence of postoperative bleeding, perforation and postoperative stricture were evaluated as short-term outcomes. Overall survival, and local recurrence-free survival were evaluated as long-term outcomes. RESULTS: The rate of en bloc resection, complete resection and curative resection were 94.6%, 86.5% and 78.4%, respectively. No perforation was observed. 1 (2.7%) patient experienced postoperative bleeding. During the median observation of 43 months, 3 (8.6%) patients experienced esophageal stricture, successfully managed by balloon dilation. 3(8.6%) patients had local recurrence after ESD with 5-year local recurrence-free survival rate of 91.4%. During the observation period, 4 patients died of other reasons. The 1, 3, 5-year overall survival rates were 97.1%, 97.1% and 91.4%. CONCLUSIONS: The short-term outcomes indicate ESD is technically difficult with lower resection completeness in patients after gastrectomy, while the long-term outcomes are rather favorable.

A risk-scoring system to predict clinical failure for patients with achalasia after peroral endoscopic myotomy.

BACKGROUND AND AIMS: We aimed to establish a predictive model and develop a simple risk-scoring system (Zhongshan POEM Score) to help clinicians to characterize high-risk patients for clinical failure after peroral endoscopic myotomy (POEM). METHODS: A total of 1538 patients with achalasia treated with POEM with available follow-up data were included in this study and were randomly classified to the training cohort (n = 769) or internal validation cohort (n = 769). A risk-scoring system was developed using multivariate Cox regression analysis in the training cohort. The system was then internally validated by survival analysis in the validation cohort. RESULTS: During a median follow-up time of 42 months, 109 patients had clinical failure. In the training stage, 3 risk factors for clinical failure were weighted with point values: previous treatment (2 points), intraprocedural mucosal injury (2 points for type I and 6 points for type II), and clinical reflux (3 points). The patients were categorized into low-risk and high-risk groups. In the validation stage, Kaplan-Meier curves differed significantly between the 2 groups. Patients in the high-risk group had a significantly higher risk of clinical failure than those in the low-risk group (hazard ratio, 3.99; 95% confidence interval, 2.31-6.91; P < .001). Satisfactory discrimination and calibration were shown. CONCLUSIONS: This risk-scoring system demonstrated good performance in predicting clinical failure in patients who underwent POEM.

Microscopic positive tumor margin does not increase the rate of recurrence in endoscopic resected gastric mesenchymal tumors compared to negative tumor margin.

BACKGROUND: The endoscopic resection of gastrointestinal mesenchymal tumors (GIMTs) is widely accepted because of its minimal invasiveness. However, one major concern is the high rate of positive microscopic margins remaining following endoscopic resection, which was thought to be related to a higher risk of recurrence. This study aimed to determine whether positive margins affect the recurrence rate of gastric GIMTs and the factors associated with positive margins. METHODS: Patients with gastric GIMTs were recruited retrospectively from January 2008 to December 2013. Clinical and pathological features, endoscopic procedure information, and follow-up data were collected and analyzed. RESULTS: The study included 777 patients. All tumors were removed along with the pseudocapsule without macroscopic residual (ER0), and the median tumor size was 15.2 mm (range 3-100 mm). Pathological evaluation revealed 371(47.7%) GISTs. The rate of microscopic R1 resection rate was 47.0% (443/777). In a stepwise multivariate analysis, a significantly increased incidence of R1 resection was recorded for the GISTs (OR 11.13, 95% CI 3.00-41.37). In a subgroup analysis of GISTs, a univariate analysis revealed that EFTR achieved a higher rate of R0 resection (OR 0.56, 95% CI 0.31-1.00), but it was proven insignificant in a stepwise multivariate analysis. Local recurrence occurred in two patients (0.3%) during a mean follow-up time of 34.2 months. Differences in the recurrence rates between the R0 and R1 groups were statistically insignificant (P = 0.841). CONCLUSIONS: R1 resection for gastric GIMTs is not related to a higher recurrence rate than R0 resection, and ER0 resection is sufficient for gastric GIMTs.

Effect of peroral endoscopic myotomy in geriatric patients: a propensity score matching study.

BACKGROUND: Peroral endoscopic myotomy (POEM) is a safe and effective approach for achalasia. However, the safety, feasibility, perioperative and long-term efficacy in treating geriatric patients has not been well evaluated. METHODS: Data of 2367 patients diagnosed with achalasia and treated with POEM in the Endoscopy Center, Zhongshan Hospital, Fudan University from August 2010 to December 2017 were retrospectively reviewed. Last follow-up was in December 2018. Propensity score matching based on baseline characteristics was used to adjust for confounding. With a caliper of 0.01 in propensity scoring, 139 patients aged ≥ 65 years were matched at a 1:2 ratio with 275 patients aged < 65 years. Perioperative complications and long-term outcomes were compared between the two groups. RESULTS: After propensity score matching, the two groups had similar baseline clinical characteristics and distribution of propensity scores. The mean age was 70.22 years in geriatric patients and 42.02 in younger patients. Technical failure occurred in one geriatric and one non-geriatric patients (p = 0.485). The procedural time in geriatric patients was similar to younger patients [50 (interquartile range (IQR) 36-76) vs. 50 (IQR 36-70) min, p = 0.398]. There were also no significant differences in major perioperative adverse events (2.88% vs. 2.18%, p = 0.663) and hospitalization length (median 3 vs. 3 days, p = 0.488). During a median follow-up period of 41 months (IQR 26-60), mean decrease in Eckardt score and pressure of the LES were 6.63 and 11.9 mmHg in geriatric patients, which were similar to the change in non-geriatric patients (6.49 and 11.6 mmHg, p = 0.652 and 0.872, respectively). Clinical reflux occurred in 23.53% geriatric patients and 21.59% non-geriatric patients (p = 0.724). 5-year success rate of 92.94% was achieved in geriatric patients and 92.61% in younger patients (log-rank p = 0.737). CONCLUSIONS: POEM is a safe and reliable treatment in geriatric achalasia patients with confirmed short-term and long-term efficacy compared with those in non-geriatric patients.

Self-expandable metallic stenting as a bridge to elective surgery versus emergency surgery for acute malignant right-sided colorectal obstruction.

BACKGROUND: The use of a self-expandable metallic stent (SEMS) as a bridge to surgery has increased for patients with obstructing colorectal cancer. However, relatively few reports have compared SEMS as a bridge to elective surgery for acute malignant obstruction of the right-sided colon (MORC) vs. emergency surgery (ES). This study aimed to evaluate the benefits of elective surgery after SEMS placement vs. ES for patients (including stage IV cases) with acute MORC. METHODS: Patients with acute MORC who underwent radical resection for a primary tumour from July 2008 to November 2016 at Zhongshan Hospital of Fudan University were retrospectively enrolled. Postoperative short-term outcomes, progression-free survival (PFS), and overall survival (OS) were compared between the SEMS and ES groups. RESULTS: In total, 107 patients with acute MORC (35 in the SEMS group and 72 in the ES group) were included for analysis. The Intensive Care Unit admission rate was lower (11.4% vs. 34.7%, P = 0.011), the incidence of complications was reduced (11.4% vs. 29.2%, P = 0.042), and the postoperative length of hospitalisation was significantly shorter (8.23 ± 6.50 vs. 11.18 ± 6.71 days, P = 0.033) for the SEMS group. Survival curves showed no significant difference in PFS (P = 0.506) or OS (P = 0.989) between groups. Also, there was no significant difference in PFS and OS rates between patients with stage II and III colon cancer. After colectomy for synchronous liver metastases among stage IV patients, the hepatectomy rates for the SEMS and ES groups were 85.7% and 14.3%, respectively (P = 0.029). The hazard ratio for colectomy alone vs. combined resection was 3.258 (95% CI 0.858-12.370; P = 0.041). CONCLUSION: Stent placement offers significant advantages in terms of short-term outcomes and comparable prognoses for acute MORC patients. For synchronous liver metastases, SEMS placement better prepares the patient for resection of the primary tumour and liver metastasis, which contribute to improved survival.

Application of convolutional neural network in the diagnosis of the invasion depth of gastric cancer based on conventional endoscopy.

BACKGROUND AND AIMS: According to guidelines, endoscopic resection should only be performed for patients whose early gastric cancer invasion depth is within the mucosa or submucosa of the stomach regardless of lymph node involvement. The accurate prediction of invasion depth based on endoscopic images is crucial for screening patients for endoscopic resection. We constructed a convolutional neural network computer-aided detection (CNN-CAD) system based on endoscopic images to determine invasion depth and screen patients for endoscopic resection. METHODS: Endoscopic images of gastric cancer tumors were obtained from the Endoscopy Center of Zhongshan Hospital. An artificial intelligence-based CNN-CAD system was developed through transfer learning leveraging a state-of-the-art pretrained CNN architecture, ResNet50. A total of 790 images served as a development dataset and another 203 images as a test dataset. We used the CNN-CAD system to determine the invasion depth of gastric cancer and evaluated the system's classification accuracy by calculating its sensitivity, specificity, and area under the receiver operating characteristic curve. RESULTS: The area under the receiver operating characteristic curve for the CNN-CAD system was .94 (95% confidence interval [CI], .90-.97). At a threshold value of .5, sensitivity was 76.47%, and specificity 95.56%. Overall accuracy was 89.16%. Positive and negative predictive values were 89.66% and 88.97%, respectively. The CNN-CAD system achieved significantly higher accuracy (by 17.25%; 95% CI, 11.63-22.59) and specificity (by 32.21%; 95% CI, 26.78-37.44) than human endoscopists. CONCLUSIONS: We constructed a CNN-CAD system to determine the invasion depth of gastric cancer with high accuracy and specificity. This system distinguished early gastric cancer from deeper submucosal invasion and minimized overestimation of invasion depth, which could reduce unnecessary gastrectomy.

Using a deep learning system in endoscopy for screening of early esophageal squamous cell carcinoma (with video).

BACKGROUND AND AIMS: Few artificial intelligence-based technologies have been developed to improve the efficiency of screening for esophageal squamous cell carcinoma (ESCC). Here, we developed and validated a novel system of computer-aided detection (CAD) using a deep neural network (DNN) to localize and identify early ESCC under conventional endoscopic white-light imaging. METHODS: We collected 2428 (1332 abnormal, 1096 normal) esophagoscopic images from 746 patients to set up a novel DNN-CAD system in 2 centers and prepared a validation dataset containing 187 images from 52 patients. Sixteen endoscopists (senior, mid-level, and junior) were asked to review the images of the validation set. The diagnostic results, including accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), were compared between the DNN-CAD system and endoscopists. RESULTS: The receiver operating characteristic curve for DNN-CAD showed that the area under the curve was >96%. For the validation dataset, DNN-CAD had a sensitivity, specificity, accuracy, PPV, and NPV of 97.8%, 85.4%, 91.4%, 86.4%, and 97.6%, respectively. The senior group achieved an average diagnostic accuracy of 88.8%, whereas the junior group had a lower value of 77.2%. After referring to the results of DNN-CAD, the average diagnostic ability of the endoscopists improved, especially in terms of sensitivity (74.2% vs 89.2%), accuracy (81.7% vs 91.1%), and NPV (79.3% vs 90.4%). CONCLUSIONS: The novel DNN-CAD system used for screening of early ESCC has high accuracy and sensitivity, and can help endoscopists to detect lesions previously ignored under white-light imaging.

Clinical and endoscopic predictors for intraprocedural mucosal injury during per-oral endoscopic myotomy.

BACKGROUND AND AIMS: Mucosal injury (MI) is one of the most common perioperative adverse events of per-oral endoscopic myotomy (POEM). Severe undertreated MI may lead to contamination of the tunnel and even mediastinitis. This study explored the characteristics, predictors, and management approaches of intraoperative MI. METHODS: A retrospective review of the prospectively collected database at a large tertiary referral endoscopy unit was conducted for all patients undergoing POEM between August 2010 and March 2016. MI was graded according to the difficulty of repair (I, easy to repair; II, difficult to repair). The primary outcomes were the incidence and predictors of intraoperative MI. Secondary outcomes were MI details and the corresponding treatment. RESULTS: POEM was successfully performed in 1912 patients. A total of 338 patients experienced 387 MIs, for an overall frequency of 17.7% (338/1912). Type II MI was rare, with a frequency of 1.7% (39/1912). Major adverse events were more common in patients with MI than in those without MI (6.2% vs 2.5%, P < .001). On multivariable analysis, MI was independently associated with previous Heller myotomy (odds ratio [OR], 2.094; P = .026), previous POEM (OR, 2.441; P = .033), submucosal fibrosis (OR, 4.530; P < .001), mucosal edema (OR, 1.834; P = .001), and tunnel length ≥13 cm (OR, 2.699; P < .001). Previous POEM (OR, 5.005; P = .030) and submucosal fibrosis (OR, 12.074; P < .001) were significant predictors of type II MI. POEM experience >1 year was a protective factor for MI (OR, .614; P = .042) and type II MI (OR, .297; P = .042). CONCLUSIONS: MI during POEM is common, but type II injury is rare. Previous POEM and submucosal fibrosis were significant predictors of type II mucosal injury. POEM experience after the learning curve reduces the risk of MI.

The effect of prior treatment on clinical outcomes in patients with achalasia undergoing peroral endoscopic myotomy.

BACKGROUND: Peroral endoscopic myotomy (POEM) is a treatment option for patients with previous surgical or endoscopic treatment. We aimed to evaluate the influence of prior treatment on perioperative and follow-up outcomes in patients undergoing POEM. METHODS: From August 2010 to December 2014, a total of 1384 patients with achalasia underwent POEM at our center. We retrospectively reviewed 849 patients who completed follow-up. Patients with an Eckardt score ≥ 4 after POEM were considered to have a clinical failure. We compared variables between patients with and without prior treatment. We analyzed risk factors for perioperative major adverse events, and clinical reflux and failure during follow-up.  RESULTS: 245 patients (28.9 %) had undergone prior treatment, and 34 patients (4.0 %) experienced a major adverse event associated with the POEM procedure. During a median follow-up of 23 months (range 1 - 71), clinical reflux occurred in 203 patients (23.9 %) and clinical failure was recorded for 94 patients (11.1 %). Patients with prior treatment had a longer procedure duration (P = 0.001) and longer hospital stay after POEM (P = 0.001). Prior treatment was not an independent risk factor for major adverse events or clinical reflux (odds ratio [OR] 1.19, P = 0.65; OR 1.26, P = 0.19; logistic regression), but it did increase the rate of clinical failure during follow-up (hazard ratio 1.90, P = 0.002; Cox regression). CONCLUSIONS: POEM was performed safely with a low rate of major adverse events in patients with achalasia who had undergone prior surgical or endoscopic treatment. However, prior treatment increased the risk of clinical failure after POEM.

Endoscopic full-thickness resection (EFTR) without laparoscopic assistance for nonampullary duodenal subepithelial lesions: our clinical experience of 32 cases.

BACKGROUND: Standard treatment for nonampullary duodenal tumors has not yet been established. In case of tumors originated from the muscularis propria (MP) layer and adherent to the serosa layer, the lesions can not be completely removed by ESD. However, with the development of the endoscopic suture technique, endoscopic full-thickness resection (EFTR) of duodenal subepithelial lesions has become possible. METHODS: We retrospectively analyzed 32 patients with nonampullary duodenal subepithelial lesions who underwent EFTR between February 2012 and January 2017. The suturing method, complications that occurred during and after the operations, perioperative management, tumor characteristics, and pathological findings were analyzed in all patients. RESULTS: The complete resection rate was 100%; all patients successfully received EFTR except for one patient who required conversion to open surgery. Severe abdominal pain was observed after the operation in one patient who then received laparoscopic exploration, and the possibility of delayed perforation was considered. Another patient showed a decline in blood oxygen saturation (SO2) and was transferred to the intensive care unit (ICU) for further management. Delayed bleeding and fistula were not observed. All patients achieved complete remission. CONCLUSION: EFTR is a safe, minimally invasive treatment modality that ensures complete eradication of the duodenal subepithelial lesions.