Clinical and endoscopic features of metachronous gastric cancer with possible lymph node metastasis after endoscopic submucosal dissection and Helicobacter pylori eradication.

BACKGROUND: Several studies have reported the metachronous gastric cancers (MGCs) with possible lymph node metastasis (LNM) after endoscopic submucosal dissection (ESD) and Helicobacter pylori (H. pylori) eradication in which a curative ESD had not been achieved. There have been no published reports of evaluations of the features of patients with MGC with possible LNM after ESD and H. pylori eradication. METHODS: We identified 264 patients with 369 MGCs after H. pylori eradication among the 4354 patients with 5059 early gastric cancers (EGCs) who underwent ESD between 1999 and 2017 and divided them into two groups: patients with MGCs with possible LNM (Group I) and patients with MGCs undergone curative ESD (Group II). We retrospectively compared the features of patients with MGCs and patients with EGCs at index ESD in the two groups. RESULT: Group I consisted of 20 patients with 21 MGCs, and Group II consisted of 244 patients with 348 MGCs. Group I lesions were significantly more common in the posterior wall than in the lesser curvature (odds ratio [OR] = 3.97; 95% confidence intervals [CI] 1.20-13.10). Development of Group I was significantly more common in patients with a body mass index (BMI) < 19.0 kg/m2 than in patients with a BMI ≥ 19.0 kg/m2 at index ESD (OR = 4.44; 95% CI 1.30-15.20). CONCLUSIONS: During surveillance endoscopy after gastric ESD and H. pylori eradication, the posterior wall should be carefully examined to detect MGCs early. Lower BMI may be associated with the development of MGCs with possible LNM.

Risk of Pancreatitis Following Biliary Stenting With/Without Endoscopic Sphincterotomy: A Randomized Controlled Trial.

BACKGROUND & AIMS: The efficacy of endoscopic sphincterotomy (ES) before endoscopic transpapillary biliary drainage in preventing post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) has not been established. The aim of this study was to evaluate the effect of performing ES before biliary stent/tube placement on the occurrence of PEP. METHODS: Three hundred seventy patients with biliary stricture requiring endoscopic biliary stenting were enrolled and randomly allocated to the ES group (n = 185) or non-ES group (n = 185). All participants were followed up for 30 days after the procedure. The data and occurrence of adverse events were prospectively collected. The primary outcome measure of this study was the incidence of PEP within 2 days of initial transpapillary biliary drainage. Secondary outcome measures were the incidence of other adverse events related to biliary stent/tube placement. RESULTS: PEP occurred in 36 patients (20.6%) in the non-ES group and in 7 patients (3.9%) in the ES group (P < .001). The difference in the incidence of PEP between the 2 groups in the per-protocol population was 16.7% (95% confidence interval, 10.1%-23.3%), which was not within the noninferiority margin of 6%. Except for bleeding, the incidences of other adverse events were not significantly different between the groups. CONCLUSION: ES before endoscopic biliary stenting could have the preventive effect on the occurrence of PEP in patients with biliary stricture. University Hospital Medical Information Network Number, UMIN000025727.University Hospital Medical Information Network Clinical Trial Registry URL: https://www.umin.ac.jp/ctr/index.htm.

The effect of antithrombotic drug use on delayed bleeding with esophageal endoscopic resection.

BACKGROUND AND AIM: Whether antithrombotic drugs increase the risk of post-esophageal endoscopic resection bleeding is unknown. This study examined the effect of antithrombotic drugs, aspirin, thienopyridine, direct oral anticoagulants (DOAC), and warfarin, on post-esophageal endoscopic resection bleeding. METHODS: We enrolled 957 patients (1202 esophageal tumors) treated with endoscopic resection and classified them based on antithrombotic drug use as no use, aspirin, thienopyridine, DOAC, and warfarin. Patients using antiplatelet drugs (i.e. aspirin and thienopyridine) were further sub-classified based on their continued or discontinued use before endoscopic resection. The bleeding rates were compared between these groups to assess the effects of antithrombotic drug use and interruption of antiplatelet therapy on post-esophageal endoscopic resection bleeding. RESULTS: The post-endoscopic resection bleeding rate was 0.3% (95% CI, 0.1-1) in the group without antithrombotic drug use, 4.5% (95% CI, 0.1-23) in the aspirin-continued group, 2.9% (95% CI, 0.1-15) in the aspirin-discontinued group, 0% (95% CI, 0-78) in the replaced thienopyridine with aspirin group, 0% (95% CI, 0-26) in the thienopyridine-discontinued group, 13% (95% CI, 1.6-38) in the DOAC group, and 0% (95% CI, 0-45) in the warfarin group. The post-endoscopic resection bleeding rate in the DOAC group was significantly higher than that in the group without antithrombotic drugs (P = 0.003). The post-endoscopic resection bleeding rates did not differ between the other groups. CONCLUSIONS: Our results suggest that discontinuing aspirin is not necessary for esophageal endoscopic resection while we must be careful regarding DOAC.

Long-term outcomes of standardized colonic stenting using WallFlex as a bridge to surgery: Multicenter prospective cohort study.

OBJECTIVES: The oncological outcomes, especially high recurrence rate, of bridge-to-surgery (BTS) self-expandable metallic stent (SEMS) placement remain concerning, emphasizing the necessity of standardized SEMS placement. However, its impact on long-term BTS outcomes is unknown. We investigated the long-term outcomes of BTS colonic stenting using standardized SEMS placement. METHODS: This prospective, multicenter cohort study conducted at 46 hospitals in Japan (March 2012 to October 2013) included consecutive patients with stage II and III obstructive colorectal cancer managed with BTS SEMS placement. The SEMS placement technique was standardized by information dissemination among the participating hospitals. The primary outcome was overall survival (OS) after SEMS placement, and the secondary outcomes were relapse-free survival (RFS), recurrence, and short-term outcomes of SEMS placement and surgery. RESULTS: The 1-, 3-, and 5-year OS rates were 94.1%, 77.4%, and 67.4% (Kaplan-Meier), respectively, with high technical success (99.0%, 206/208) and low perforation (1.9%, 4/208) rates. The 1-, 3-, and 5-year RFS rates were 81.6%, 65.6%, and 57.9% (Kaplan-Meier), respectively, and the overall recurrence rate was 31.0% (62/200). The RFS rate was significantly poorer in patients with perforation (n = 4) than in those without perforation (n = 196) (log-rank P = 0.017); moreover, perforation was identified as an independent factor affecting RFS (hazard ratio 3.31; 95% confidence interval 1.03-10.71, multivariate Cox regression). CONCLUSION: This large, prospective, multicenter study revealed satisfactory long-term outcomes of BTS colonic stenting using a standardized SEMS insertion method, which might be specifically due to the reduced perforation rate. (UMIN000007953).

[Idiopathic esophageal submucosal hematoma during antithrombotic therapy for essential thrombocythemia].

A 73-year-old woman was hospitalized with sudden chest pain and hematemesis. Chest computed tomography and upper gastrointestinal endoscopy revealed an idiopathic submucosal hematoma from the cervical esophagus to the esophagogastric mucosal junction. Idiopathic esophageal submucosal hematoma is often prone to a bleeding tendency of an underlying disorder. The patient had a history of essential thrombocythemia (ET) and was taking aspirin. She successfully recovered after aspirin discontinuation and conservative treatment; however, died of cardiopulmonary arrest in the ward on day 9 of hospitalization. The autopsy revealed that the cause of death was pulmonary thromboembolism. This is the first report of ET with submucosal hematoma of the esophagus. The possibility of an esophageal submucosal hematoma should be considered when patients with ET complain of chest pain since ET and treatment with aspirin are considered risk factors for bleeding. Additionally, close attention should be focused on the risk of developing thrombosis if a patient with myeloproliferative neoplasm is required to discontinue antithrombotic therapy due to a bleeding event.

A prospective multicenter study of endoscopic ultrasound-guided fine needle biopsy using a 22-gauge Franseen needle for pancreatic solid lesions.

BACKGROUND AND AIM: While encouraging data of endoscopic ultrasound (EUS)-guided fine-needle biopsy (EUS-FNB) using a 22-gauge Franseen needle have been reported, large-scale data of per pass and quantitative analyses are still lacking. METHODS: This was a multicenter prospective study of EUS-FNB using the 22-gauge Franseen needle for a pancreatic solid lesion. Cytological and histological analyses per pass were evaluated and semi-quantitative analyses were performed on core tissue and blood contamination. Primary end-point was diagnostic accuracy per session. Prognostic factors were analyzed for diagnostic accuracy, sensitivity, core tissue, and blood contamination. RESULTS: A total of 629 passes were performed in 244 cases at 14 centers between 2018 and 2019. The median tumor size was 29 mm, and the puncture was transduodenal in 43%. The median pass number was 2. Diagnostic accuracy per session, at a first pass, and per pass were 93%, 90%, and 88%. In 198 cases with pancreatic cancer, diagnostic sensitivity per session, at a first pass, and per pass were 94%, 89%, and 89%. The rates of core tissue score of 4 and blood contamination score of 3 were 50% and 47%. The adverse event rate was 1.6%. In the multivariate analysis, tumor size ≤20 mm (odds ratio [OR] of 0.46, P = 0.03), transduodenal puncture (OR of 0.53, P = 0.04), and suction (OR of 0.16, P = 0.01) were associated with lower diagnostic accuracy. CONCLUSIONS: The EUS-FNB using the 22-gauge Franseen needle for pancreatic solid lesions showed high per pass and overall diagnostic accuracy.

Diagnostic outcomes of esophageal cancer by artificial intelligence using convolutional neural networks.

BACKGROUND AND AIMS: The prognosis of esophageal cancer is relatively poor. Patients are usually diagnosed at an advanced stage when it is often too late for effective treatment. Recently, artificial intelligence (AI) using deep learning has made remarkable progress in medicine. However, there are no reports on its application for diagnosing esophageal cancer. Here, we demonstrate the diagnostic ability of AI to detect esophageal cancer including squamous cell carcinoma and adenocarcinoma. METHODS: We retrospectively collected 8428 training images of esophageal cancer from 384 patients at the Cancer Institute Hospital, Japan. Using these, we developed deep learning through convolutional neural networks (CNNs). We also prepared 1118 test images for 47 patients with 49 esophageal cancers and 50 patients without esophageal cancer to evaluate the diagnostic accuracy. RESULTS: The CNN took 27 seconds to analyze 1118 test images and correctly detected esophageal cancer cases with a sensitivity of 98%. CNN could detect all 7 small cancer lesions less than 10 mm in size. Although the positive predictive value for each image was 40%, misdiagnosing shadows and normal structures led to a negative predictive value of 95%. The CNN could distinguish superficial esophageal cancer from advanced cancer with an accuracy of 98%. CONCLUSIONS: The constructed CNN system for detecting esophageal cancer can analyze stored endoscopic images in a short time with high sensitivity. However, more training would lead to higher diagnostic accuracy. This system can facilitate early detection in practice, leading to a better prognosis in the near future.

Factors related to difficult self-expandable metallic stent placement for malignant colonic obstruction: A post-hoc analysis of a multicenter study across Japan.

BACKGROUND AND AIM: Colorectal cancer patients often present with large bowel obstruction. Elective placement of a self-expandable metallic stent (SEMS) can relieve obstruction, but can be challenging. Previous studies have compared cases by outcomes only, but the present study investigated successful cases only to identify factors related to prolonged and difficult SEMS placement in patients with malignant colonic obstruction. METHODS: A post-hoc analysis of a multicenter clinical trial conducted between March 2012 and October 2013 at 46 facilities across Japan (UMIN000007953) was carried out; 511 patients who required SEMS placement for acute colorectal obstruction or symptomatic stricture secondary to malignant neoplasm were enrolled. Technical success rates and procedure times were recorded. Clinical and interventional parameters were investigated for their potential effect on procedure time by univariate and multivariate analyses. RESULTS: Technical success rate of SEMS placement was 98%. Median procedure time was 30 (range, 4-170) min. In 27% of patients, procedure time exceeded 45 min, indicating technically difficult placement. Multivariate analyses showed significant associations between technically difficult placement and a ColoRectal Obstruction Scoring System (CROSS) score of 0 before SEMS placement (odds ratio [OR], 1.6; P < 0.05), tumor site in the right colon (OR, 2.5; P < 0.0001), stricture length ≥5 cm (OR, 2.2; P < 0.001), peritoneal carcinomatosis (OR, 1.7; P < 0.05), and multiple SEMS placement (OR, 8.0; P < 0.01). CONCLUSION: Clinicians must anticipate technical challenges in cases with peritoneal carcinomatosis, a CROSS score of 0, or expansive strictures; such cases require experienced clinicians to carry out SEMS placement.

Clinicopathological and prognostic significance of MUC13 and AGR2 expression in intraductal papillary mucinous neoplasms of the pancreas.

BACKGROUND: Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a primary pancreatic ductal epithelial neoplasm with the potential to develop into an invasive adenocarcinoma. This study aimed to investigate the clinicopathologic and prognostic significance of four potential biomarkers for the preoperative evaluation of patients with IPMN. MATERIALS AND METHODS: Clinicopathologic materials from 104 patients with IPMN who underwent surgical resection at Jichi Medical University Hospital were analyzed. IPMNs (110 lesions in total) were histologically classified into low-grade IPMN (Group 1; n = 68), high-grade IPMN (Group 2; n = 16), or IPMN with an associated invasive carcinoma (Group 3; n = 26). We evaluated the immunohistochemical expression of MUC13, AGR2, FUT8, and FXYD3, which were previously reported to be overexpressed in pancreatic ductal adenocarcinoma. RESULTS: The expression of MUC13 was more common in Group 3 compared with groups 1 and 2 (p < 0.001) and was associated with poor prognosis (p = 0.004). The expression of MUC13 was not associated with age, sex, tumor location, histological subtype, lymphatic or vascular invasion, or neural invasion. In most cases of IPMN, the loss of expression of AGR2 appeared to show an association with tumor recurrence and poorly differentiated histology of invasive carcinoma; however, this association was not statistically significant. The expressions of FUT8 and FXYD3were not associated with the clinicopathological features of IPMNs. CONCLUSIONS: The results suggest that MUC13 overexpression and loss of expression of AGR2 may predict the progression of IPMN and an unfavorable prognosis in patients with IPMN.

Delayed Bleeding Following Cold Snare Polypectomy for Small Colorectal Polyps in Patients Taking Antithrombotic Agents.

BACKGROUND: This study compared the incidence of delayed bleeding following 2 methods of cold snare polypectomy for colorectal polyps in patients taking antithrombotic agents. METHODS: Patients undergoing cold snare polypectomy for colorectal polyps ≤10 mm without discontinuation of antithrombotic agents were enrolled. This was a retrospective study of a prospectively collected cohort based on a historical comparison of 2 time periods. A traditional cold snare was used between January 2012 and December 2013 and a dedicated cold snare was used between January 2014 and December 2015. Patients' and polyps' characteristics, antithrombotic agents used, the snare used, the number of clips used, and adverse events were documented from a hospital online database. Delayed bleeding was defined as bleeding that required endoscopic treatment within 2 weeks after polypectomy. The submucosal layer of the resected polyps (6 to 10 mm) was histologically examined for the presence of injured arteries. RESULTS: A total of 172 patients having 370 eligible polyps were enrolled; traditional cold snare group, N=100 (212 polyps) and dedicated cold snare group, N=72 (158 polyps). The patients' and polyps' characteristics were similar between the 2 groups. Hemostatic clips were used more often with the traditional than dedicated cold snares [33/100 (33%) vs. 13/72 (18%), P=0.044]. Delayed bleeding following cold snare polypectomy occurred in 1.2% (2/172); 0% (0/72) with dedicated snare versus 2% (2/100) with the traditional snare (P=0.63). The presence of histologically demonstrated injured submucosal arteries with the dedicated cold snare was significantly less than with the traditional cold snare [4.1% (4/98) vs. 16% (17/105), P=0.009]. CONCLUSIONS: Colorectal polyps ≤10 mm can be removed without an increase in delayed bleeding using dedicated cold snare polypectomy in patients taking antithrombotic agents.

International study of endoscopic management of distal malignant biliary obstruction combined with duodenal obstruction.

OBJECTIVE: Endoscopic transpapillary or endoscopic ultrasound (EUS)-guided stent placement is used for nonresectable distal malignant biliary obstruction. We conducted a retrospective study to evaluate endoscopic biliary drainage in patients with duodenal obstruction. METHODS: We included consecutive patients who underwent endoscopic biliary drainage combined with a duodenal stent at 16 referral centers in four Asian countries. The primary outcome was time to recurrent biliary obstruction (TRBO). We assessed TRBO according to the sequence of biliary and duodenal obstruction (group 1/2/3, biliary obstruction first/concurrent/duodenal obstruction first, respectively) or the location of duodenal obstruction (type I/II/III, proximal to/affecting/distal to the ampulla, respectively). We also evaluated functional success and adverse events. RESULTS: We included 110 patients (group1/2/3, 67/29/14 patients; type I/II/III, 45/46/19 patients; endoscopic retrograde cholangiopancreatography [ERCP]/EUS-guided choledocoduodenostomy/EUS-guided hepaticogastrostomy, 90/10/10 patients, respectively). The median TRBO of all cases was 450 days (interquartile range, 212-666 days) and functional success was achieved in 105 cases (95%). The TRBO did not differ significantly by the timing or location of duodenal obstruction (p = .30 and .79, respectively). The TRBO of metal stents (n = 96) tended to be longer compared with plastic stents (n = 14, p = .083). Compared with ERCP, EUS-guided biliary drainage was associated with a higher rate of adverse events. CONCLUSION: Transpapillary or transmural endoscopic biliary drainage with a duodenal stent was effective, irrespective of the timing or location of duodenal obstruction. A prospective study is required considering the tradeoff of technical success rate, stent patency, and adverse events (ClinicalTrials.gov number, NCT02376907).

Multicenter study of endoscopic preoperative biliary drainage for malignant hilar biliary obstruction: E-POD hilar study.

BACKGROUND AND AIM: Endoscopic nasobiliary drainage (ENBD) is often recommended in preoperative biliary drainage (PBD) for hilar malignant biliary obstruction (MBO), but endoscopic biliary stent (EBS) is also used in the clinical practice. We conducted this large-scale multicenter study to compare ENBD and EBS in this setting. METHODS: A total of 374 cases undergoing PBD including 281 ENBD and 76 EBS for hilar MBO in 29 centers were retrospectively studied. RESULTS: Extrahepatic cholangiocarcinoma (ECC) accounted for 69.8% and Bismuth-Corlette classification was III or more in 58.8% of the study population. Endoscopic PBD was technically successful in 94.6%, and adverse event rate was 21.9%. The rate of post-endoscopic retrograde cholangiopancreatography pancreatitis was 16.0%, and non-endoscopic sphincterotomy was the only risk factor (odds ratio [OR] 2.51). Preoperative re-intervention was performed in 61.5%: planned re-interventions in 48.4% and unplanned re-interventions in 31.0%. Percutaneous transhepatic biliary drainage was placed in 6.4% at the time of surgery. The risk factors for unplanned procedures were ECC (OR 2.64) and total bilirubin ≥ 10 mg/dL (OR 2.18). In surgically resected cases, prognostic factors were ECC (hazard ratio [HR] 0.57), predraiange magnetic resonance cholangiopancreatography (HR 1.62) and unplanned re-interventions (HR 1.81). EBS was not associated with increased adverse events, unplanned re-interventions, or a poor prognosis. CONCLUSIONS: Our retrospective analysis did not demonstrate the advantage of ENBD over EBS as the initial PBD for resectable hilar MBO. Although the technical success rate of endoscopic PBD was high, its re-intervention rate was not negligible, and unplanned re-intervention was associated with a poor prognosis in resected hilar MBO.

A Prospective Multicenter Study of a Fully Covered Metal Stent in Patients with Distal Malignant Biliary Obstruction: WATCH-2 Study.

BACKGROUND: Both fully covered (FC) and partially covered (PC) self-expandable metal stents (SEMSs) are now commercially available for distal malignant biliary obstruction (MBO). While FCSEMS can be easily removed at the time of re-interventions, it is theoretically prone to migration. However, few comparative data between FC and PC SEMSs have been reported. AIMS: The aim of this study was to compare clinical outcomes of FCSEMS with those of PCSEMS. METHODS: This was a multicenter, prospective study of FCSEMS for unresectable distal MBO with a historical control of PCSEMS, which was previously reported as the WATCH study. The primary outcome was recurrent biliary obstruction (RBO), and secondary outcomes were stent migration, stent removal, stent-related adverse events, and survival. RESULTS: A total of 151 cases with unresectable distal MBO undergoing FCSEMS placement were enrolled and compared with a historical cohort of 141 cases undergoing PCSEMS placement. No significant differences were found in the rate of RBO (29 vs. 33%; P = 0.451), time to RBO (318 vs. 373 days; P = 0.382), and survival (229 vs. 196 days; P = 0.177) between FCSEMS and PCSEMS. The rate of stent migration also did not differ significantly between the two groups (14 vs. 8%; P = 0.113). The removal of FCSEMSs was successful in all 24 attempted cases (100%). CONCLUSIONS: FCSEMSs appeared comparable to PCSEMSs in terms of RBO without a significant increase in stent migration rate in patients with unresectable distal MBO. CLINICAL TRIAL REGISTRATION NUMBER: UMIN000007131.

A prospective randomized study of the use of an ultrathin colonoscope versus a pediatric colonoscope in sedation-optional colonoscopy.

BACKGROUND: Ultrathin colonoscopes (UTC) reportedly produce less pain during colonoscopy than standard colonoscopes. The aim of this study was to assess the tolerability of an UTC compared with that of a pediatric colonoscope. METHODS: A total of 270 adult patients scheduled to undergo colonoscopy were randomized, with 134 allocated to the UTC group and 136 to the pediatric colonoscope group. Pain was assessed using a visual analog scale. For all procedures, sedation was administered only if requested. Overall pain, rate and time of cecal and terminal ileum intubation, number of patients requesting sedation, adenoma detection rates (ADR), and rate of complications were measured and analyzed. RESULTS: Among all patients, the medians of maximum pain and overall pain were significantly lower in the UTC group than in the pediatric colonoscope group (23 vs. 38, P < 0.001; 12 vs. 22, P = 0.0003, respectively). Significantly fewer patients requested sedation in the UTC group than in the pediatric colonoscope group (1.4 vs. 6.6%; P = 0.0269). No significant differences were seen in either the rate and time of successful cecal and terminal ileum intubation, or in other procedure-related outcomes, including ADR. CONCLUSIONS: Compared with a pediatric colonoscope, the UTC was associated with reduced overall and maximum pain during colonoscopy, with no difference in ADR.

Asian consensus statements on endoscopic management of walled-off necrosis. Part 2: Endoscopic management.

Walled-off necrosis (WON) is a new term for encapsulated necrotic tissue after severe acute pancreatitis. Various terminologies such as pseudocyst, necroma, pancreatic abscess, and infected necrosis were previously used in the literature, resulting in confusion. The current and past terminologies must be reconciled to meaningfully interpret past data. Recently, endoscopic necrosectomy was introduced as a treatment option and is now preferred over surgical necrosectomy when the expertise is available. However, high-quality evidence is still lacking, and there is no standard management strategy for WON. The consensus meeting aimed to clarify the diagnostic criteria for WON and the role of endoscopic interventions in its management. In the Consensus Conference, 27 experts from eight Asian countries took an active role and examined key clinical aspects of WON diagnosis and endoscopic management. Statements were crafted based on literature review and expert opinion, employing the modified Delphi method. All statements were substantiated by the level of evidence and the strength of the recommendation. We created 27 consensus statements for WON diagnosis and management, including details of endoscopic procedures. When there was not enough solid evidence to support the statements, this was clearly acknowledged to facilitate future research. Proposed management strategies were formulated and are illustrated using flow charts. These recommendations, which are based on the best current scientific evidence and expert opinion, will be useful for guiding endoscopic management of WON. Part 2 of this statement focused on the endoscopic management of WON.

Asian consensus statements on endoscopic management of walled-off necrosis Part 1: Epidemiology, diagnosis, and treatment.

Walled-off necrosis (WON) is a relatively new term for encapsulated necrotic tissue after severe acute pancreatitis. Various terminologies such as pseudocyst, necroma, pancreatic abscess, and infected necrosis were previously used in the literature, resulting in confusion. The current and past terminologies must be reconciled to meaningfully interpret past data. Recently, endoscopic necrosectomy was introduced as a treatment option and is now preferred over surgical necrosectomy when the expertise is available. However, high-quality evidence is still lacking, and there is no standard management strategy for WON. The consensus meeting aimed to clarify the diagnostic criteria for WON and the role of endoscopic interventions in its management. In the Consensus Conference, 27 experts from eight Asian countries took an active role and examined key clinical aspects of WON diagnosis and endoscopic management. Statements were crafted based on literature review and expert opinion, employing the modified Delphi method. All statements were substantiated by the level of evidence and the strength of the recommendation. We created 27 consensus statements for WON diagnosis and management, including details of endoscopic procedures. When there was not enough solid evidence to support the statements, this was clearly acknowledged to facilitate future research. Proposed management strategies were formulated and are illustrated using flow charts. These recommendations, which are based on the best current scientific evidence and expert opinion, will be useful for guiding endoscopic management of WON. Part 1 of this statement focused on the epidemiology, diagnosis, and timing of intervention.

A prospective multicenter study on self-expandable metallic stents as a bridge to surgery for malignant colorectal obstruction in Japan: efficacy and safety in 312 patients.

BACKGROUND: Endoscopic stenting with a self-expandable metallic stent (SEMS) is a widely accepted procedure for malignant colonic obstruction. The Colonic Stent Safe Procedure Research Group conducted the present prospective feasibility study. METHODS: Our objectives were to estimate the safety and feasibility of SEMS placement as a bridge to surgery (BTS) for malignant colorectal obstruction. We conducted a prospective, observational, single-arm, multicenter clinical trial from March 2012 to October 2013. Each patient was treated with an uncovered WallFlex enteral colonic stent. Patients were followed up until discharge after surgery. RESULTS: A total of 518 consecutive patients were enrolled in this study. The cohort intended for BTS consisted of 312 patients (61 %), and the stent could be released in 305 patients. Technical and clinical success rates were 98 and 92 %, respectively. Elective surgery was performed in 297 patients, and emergency surgery was performed in eight patients for the treatment of complications. The overall preoperative complication rate was 7.2 %. Major complications, including perforation, occurred in 1.6 %, persistent colonic obstruction occurred in 1.0 %, and stent migration occurred in 1.3 % patients. The median time from SEMS to surgery was 16 days. Silent perforations were observed in 1.3 %. Open and laparoscopic surgery was performed in 121 and 184 patients, respectively. The tumor could be resected in 297 patients. The primary anastomosis rate was 92 %. The rate of anastomotic leakage was 4 %, and the overall stoma creation rate was 10 %. The median duration of hospitalization following surgery was 12 days. Overall postoperative morbidity and mortality rates were 16 and 0.7 %, respectively. CONCLUSIONS: This largest, multicenter, prospective study demonstrates the feasibility of SEMS placement as a BTS for malignant colorectal obstruction. SEMS serves as a safe and effective BTS with acceptable stoma creation and complication rates in patients with acute malignant colonic obstruction.

A Japanese prospective multicenter study of self-expandable metal stent placement for malignant colorectal obstruction: short-term safety and efficacy within 7 days of stent procedure in 513 cases.

BACKGROUND: Endoscopic self-expandable metal stent placement has been used as an alternative to surgery for malignant colorectal obstruction; however, factors affecting its clinical outcome are unclear. OBJECTIVE: To clarify the short-term safety and efficacy of endoscopic self-expandable metal stent placement for malignant colorectal obstruction and to identify factors associated with its clinical and technical failure. DESIGN: Prospective clinical cohort study. SETTING: Fourteen academic centers and 32 community hospitals. PATIENTS: A total of 513 consecutive patients with malignant colorectal obstruction. INTERVENTION: Endoscopic self-expandable metal stent placement, sharing of stent placement methods among participating facilities. MAIN OUTCOME MEASUREMENTS: The primary endpoint was clinical success, defined as symptom and radiological finding resolution within 24 hours. Secondary endpoints were technical success and adverse events. The follow-up period was 7 days. RESULTS: The clinical and technical success rates were 95.5% and 97.9%, respectively. Major adverse events included perforation (2.1%), stent migration (1.0%), and stent occlusion (0.8%). The main causes of perforation were the procedure itself (0.8%) and comorbidities (obstructive colitis and impending perforation) not apparent before stent placement (0.6%). Extrinsic tumor origin was independently associated with the clinical failure after stent placement (odds ratio 4.23; 95% confidence interval, 1.21-14.79; P = .02). Stricture marking trended toward a negative association with technical failure (P = .09). LIMITATIONS: Noncomparative study. CONCLUSION: Strict inclusion criteria and stricture marking may improve the technical and clinical success of stent placement.

Clinical outcome of endoscopic resection for nonampullary duodenal tumors.

BACKGROUND AND STUDY AIMS: Compared with any other location in the gastrointestinal tract, the duodenum presents the most challenging site for endoscopic resection. The aim of this study was to analyze the clinical outcomes of duodenal endoscopic resection and to assess the feasibility of the technique as a therapeutic procedure. PATIENTS AND METHODS: A total of 113 consecutive patients with 121 nonampullary duodenal tumors underwent endoscopic resection by endoscopic submucosal dissection (ESD), endoscopic mucosal resection (EMR), or polypectomy between January 2000 and September 2013. Long-term outcomes were investigated in patients with more than 1 year follow-up. RESULTS: The median tumor size was 12 mm (range 3 - 50 mm). Lesions consisted of 63 adenocarcinomas/high-grade intraepithelial neoplasias (53 %) and 57 adenomas/low-grade intraepithelial neoplasias (48 %). Endoscopic resection included 106 EMRs (87 %), 8 ESDs (7 %), and 7 polypectomies (6 %). En bloc resection was achieved in 77 lesions (64 %), and 43 lesions (35 %) underwent piecemeal resection; one procedure was discontinued due to perforation. There were 14 cases of delayed bleeding after EMR (12 %), 1 perforation (1 %) during ESD, and 1 delayed perforation (1 %) after ESD, which required emergency surgery. Of the 76 patients who were followed for more than 1 year, none of the patients died from a primary duodenal neoplasm, and there were no local recurrences during the 51-month median follow-up period (range 12 - 163 months). CONCLUSIONS: Duodenal endoscopic resection was feasible as a therapeutic procedure, but it should only be performed by highly skilled endoscopists because of its technical difficulty. Piecemeal resection by EMR is acceptable for small lesions, based on these excellent long-term outcomes.

Effectiveness of the J-Tip Guidewire for Selective Biliary Cannulation Compared to Conventional Guidewires (The JANGLE Study).

BACKGROUND: Wire-guided cannulation has become a common biliary cannulation technique worldwide. Different guidewires with various tip shapes and materials have been reportedly used for wire-guided cannulation. However, there are apparently no studies reporting changes in the biliary cannulation rate according to the type of guidewire used. AIMS: We evaluated the effectiveness of the J-tip guidewire for biliary cannulation. METHODS: We conducted a prospective, multicenter, controlled study involving patients with a native papilla who required biliary cannulation. We allocated the patients to the J-tip guidewire or angled-tip guidewire groups (groups J and A, respectively). If biliary cannulation was not achieved within 10 min, the GW was changed and cannulation was continued. RESULTS: Groups J and A consisted of 66 and 65 enrolled patients, respectively. The biliary cannulation rate with a single guidewire for the first 10 min was 84.8 % (56/66) for group J and 80.0 % (52/65) for group A. The final success rate for biliary cannulation was 100 % in both groups. The mean times necessary for biliary cannulation were 285.8 and 267.6 s in group J and group A, respectively. The incidence rates of complications (i.e., all mild pancreatitis) were 3.0 % (2/66) and 6.2 % (4/65) in group J and group A, respectively. The mean amylase concentrations were 168.0 and 297.7 IU/L in group J and group A, respectively. There were no significant differences in any results between both groups. CONCLUSION: The biliary cannulation rate of the J-tip guidewire was not significantly different from those of standard guidewires.