Guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer (second edition).

In response to the rapid and wide acceptance and use of endoscopic treatments for early gastric cancer, the Japan Gastroenterological Endoscopy Society, in collaboration with the Japanese Gastric Cancer Association, produced "Guidelines for Endoscopic Submucosal Dissection and Endoscopic Mucosal Resection for Early Gastric Cancer" in 2014, as a set of basic guidelines in accordance with the principles of evidence-based medicine. At the time, a number of statements had to be established by consensus (the lowest evidence level), as evidence levels remained low for many specific areas in this field. However, in recent years, the number of well-designed clinical studies has been increasing. Based on new findings, we have issued the revised second edition of the above guidelines that cover the present state of knowledge. These guidelines are divided into the following seven categories: indications, preoperative diagnosis, techniques, evaluation of curability, complications, long-term postoperative surveillance, and histology.

Guidelines for endoscopic diagnosis of early gastric cancer.

The Japan Gastroenterological Endoscopy Society developed the Guideline for Endoscopic Diagnosis of Early Gastric Cancer based on scientific methods. Endoscopy for the diagnosis of early gastric cancer has been acknowledged as a useful and highly precise examination, and its use has become increasingly more common in recent years. However, the level of evidence in this field is low, and it is often necessary to determine recommendations based on expert consensus only. This clinical practice guideline consists of the following sections to provide the current guideline: [I] Risk stratification of gastric cancer before endoscopic examination, [II] Detection of early gastric cancer, [III] Qualitative diagnosis of early gastric cancer, [IV] Diagnosis to choose the therapeutic strategy for gastric cancer, [V] Risk stratification after endoscopic examination, and [VI] Surveillance of early gastric cancer.

Characteristics of gastric cancer in negative test of serum anti-Helicobacter pylori antibody and pepsinogen test: a multicenter study.

BACKGROUND AND AIM: The serological risk prediction system combines the pepsinogen test and anti-Helicobacter pylori (H. pylori) antibody determination. In this system, chronic atrophic gastritis (CAG) is diagnosed using the pepsinogen test. Patients who are H. pylori negative and pepsinogen negative are classified into group A, are assumed to be H. pylori uninfected, and are at an extremely low risk for gastric cancer. However, gastric cancers are detected in this group. The aim of this study is to clarify the clinicopathological status of group A patients with gastric cancer. METHODS: A total of 109 gastric cancer patients classified as group A were enrolled in a multicenter study. Group A patients were divided into two subgroups: group AN (H. pylori uninfected) and group AP (H. pylori infected). They were compared to 183 H. pylori-infected gastric cancer patients who were not in group A. RESULTS: Of the 109 patients, only 7 were classified as group AN; the other 102 were classified as group AP. The clinicopathological features of group AP included older age, predominantly differentiated type cancer, endoscopically visualized CAG, and pepsinogen (PG) I/II ratio lower than that of group AN. In group AN, the depressed type was dominant, and the PG I/II ratio was higher than in those gastric cancer patients who were infected with H. pylori. CONCLUSION: Patients in group AP had CAG, and their gastric cancers were similar to those of H. pylori-eradicated patients. Concerning the recent ABC classification system, advanced decision criteria should be proposed to decrease the false-negative evaluation of gastric cancer risk.

Guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer.

In response to the rapid and wide acceptance and use of endoscopic treatments for early gastric cancer, the Japan Gastroenterological Endoscopy Society (JGES), in collaboration with the Japanese Gastric Cancer Association (JGCA), has produced 'Guidelines for ESD and EMR for Early Gastric Cancer', as a set of basic guidelines in accordance with the principles of evidence-based medicine. These Guidelines cover the present state of knowledge and are divided into the following seven categories: Indications, Preoperative diagnosis, Techniques, Evaluation of curability, Complications, Long-term postoperative surveillance, and Histology. Twenty-three statements were finally accepted as guidelines, and the majority of these were obtained from descriptive studies with lower evidence levels. A number of statements had to be created by consensus (the lowest evidence level), as evidence levels remain low for many specific areas in this field.

Cancer development based on chronic active gastritis and resulting gastric atrophy as assessed by serum levels of pepsinogen and Helicobacter pylori antibody titer.

Our study investigated the relationship between gastric cancer development and activity of Helicobacter pylori-associated chronic gastritis or the resulting chronic atrophic gastritis (CAG). A cohort of 4,655 healthy asymptomatic subjects, in whom serum pepsinogen (PG) and H. pylori antibody titer had been measured to assess the activity and stage of H. pylori-associated chronic gastritis, was followed for up to 16 years, and cancer development was investigated. In subjects with a serologically diagnosed healthy stomach (H. pylori-negative/CAG-negative), cancer incidence rate was low, at 16/100,000 person-years. With the establishment of H. pylori infection and progression of chronic gastritis, significant stepwise cancer risk elevations were seen from CAG-free subjects (H. pylori-positive/CAG-negative) [hazard ratio (HR) = 8.9, 95% confidence interval (CI) = 2.7-54.7] to subjects with CAG (H. pylori-positive/CAG-positive) (HR = 17.7, 95% CI = 5.4-108.6) and finally to subjects with metaplastic gastritis (H. pylori-negative/CAG-positive) (HR = 69.7, 95% CI = 13.6-502.9). In H. pylori-infected CAG-free subjects, significantly elevated cancer risk was observed in the subgroup with active inflammation-based high PG II level or potent immune response-based high H. pylori antibody titer; the former was associated with a particularly high risk of diffuse-type cancer, and both subgroups showed high cancer incidence rates of around 250/100,000 person-years, comparable to that in subjects with CAG. No such risk elevation was observed in H. pylori-infected subjects with CAG. These results clearly indicate that gastric cancer develops mainly from the gastritis-atrophy-metaplasia-cancer sequence and partly from active inflammation-based direct carcinogenesis, and that serum levels of PG and H. pylori antibody titer provide indices of cancer development in H. pylori-infected subjects.

Therapeutic strategy for patients with bleeding rectal varices complicating liver cirrhosis.

AIM: Although rupture of rectal varices is rarely encountered, it may provoke massive and fatal hemorrhage in patients with liver cirrhosis. We examined the clinical features of patients showing bleeding from rectal varices to establish a suitable therapeutic strategy for the lesions. METHODS: Twelve cirrhotic patients with bleeding rectal varices were enrolled. Surgical suture, endoscopic variceal ligation (EVL) or balloon tamponade was performed to achieve the initial hemostasis. Then, the feeding and drainage vessels of the varices were evaluated by computed tomography, and additional procedures were undertaken: EVL was performed when the sizes of the varices and feeding vessels were small. In contrast, in patients with varices of large sizes, balloon-occluded retrograde transvenous obliteration (B-RTO) was performed when single or two drainage vessels were identified, while endoscopic injection sclerotherapy (EIS) using ethanolamine oleate was carried out for varices with three or more drainage vessels. RESULTS: The Child-Pugh class was grade A in four, B in six and C in two patients. Eleven patients had received previous therapy for esophageal varices. Initial hemostasis was achieved by surgical suture in three patients, EVL in one patient and balloon tamponade in two patients. EVL, EIS and B-RTO were carried out as additional procedures in seven, three and one patient, respectively. Rebleeding from the rectal varices occurred in only one patient who underwent EVL as an additional procedure. CONCLUSION: Bleeding from rectal varices was controlled satisfactorily by the therapeutic strategy of selecting EVL, EIS or B-RTO as an additional therapy according to the size and hemodynamics of the varices.

Balloon-occluded retrograde transvenous obliteration using a microballoon catheter for intractable gastric fundal varices.

BACKGROUND AND AIM: Balloon-occluded retrograde transvenous obliteration (B-RTO) is recognized as the standard therapy for patients with gastric fundal varices in Japan; however, the procedure is difficult when drainage veins other than the gastrorenal shunt developed. The efficacy and safety of B-RTO using a microballoon catheter for such patients were evaluated. METHODS: The subjects were 99 patients with gastric fundal varices who fulfilled the criteria for receiving endoscopic and/or interventional therapies. Among these, 95 patients underwent B-RTO. Of the 95 patients, 14 were treated with the use of microballoon catheters, including nine in whom the left inferior phrenic vein was found as a secondary drainage vein in addition to the gastrorenal shunt, and five in whom a gastrorenal shunt was absent. The B-RTO procedure performed using a microballoon catheter inserted through the left inferior phrenic vein in 13 patients, and through the pericardiophrenic vein in one patient. RESULTS: The B-RTO procedure using microballoon catheters was successful in 13 of the 14 patients (93%), while in the remaining one patient, multiple drainage veins were visualized on venography. Complete obliteration of the varices was achieved in all the 13 patients by injection of 5% ethanolamine oleate iopamidol at a median volume of 25 mL (range, 11 to 40 mL) through the catheters. None of the patients showed injuries of the drainage veins or any systemic complications. CONCLUSIONS: B-RTO using a microballoon catheter is useful for the treatment of gastric fundal varices in which drainage veins other than the gastrorenal shunt developed.

Usefulness of Intraductal Placement of a Dumbbell-Shaped Fully Covered Self-Expandable Metal Stent for Post-Cholecystectomy Bile Leaks.

Background and aims: In the treatment of post-cholecystectomy bile leaks, endoscopic naso-biliary drainage (ENBD) or biliary stenting using plastic stents is the standard of care. Fully covered self-expandable metal stent (FCSEMS) placement across the sphincter of Oddi is considered a salvage therapy for refractory cases, but pancreatitis and migration are the major concerns. Intraductal placement of a dumbbell-shaped FCSEMS (D-SEMS) could avoid these drawbacks of FCMSESs. In this retrospective study, we investigated the usefulness of intraductal placement of the D-SEMS for post-cholecystectomy bile leaks. Methods: Six patients who underwent intraductal placement of the D-SEMS for post-cholecystectomy bile leaks were enrolled. This method was performed as initial treatment in three patients and as salvage treatment in three ENBD refractory cases. Results: Technical and clinical successes were obtained in 6 (100%) patients and 5 (83%) patients, respectively. One clinically unsuccessful patient required laparoscopic peritoneal lavage. The early adverse event was one case of mild pancreatitis (17%). The median duration of the D-SEMS indwelling was 61 days (42-606 days) with no migration cases, all of which were successfully removed. The median follow-up after index ERCP was 761 (range: 161-1392) days with no cases of recurrent bile leaks. Conclusions: Intraductal placement of the D-SEMS for post-cholecystectomy bile leaks might be safe and effective even in refractory cases.

Endoscopic Ultrasound-Guided Gastrojejunostomy for Malignant Afferent Loop Syndrome Using a Fully Covered Metal Stent: A Multicenter Experience.

BACKGROUND: Endoscopic-ultrasound-guided gastrojejunostomy (EUS-GJ) can be a new alternative for patients with malignant afferent loop syndrome (MALS). However, a fully covered self-expandable metal stent (FCSEMS) has not been well investigated in this setting. METHODS: This is a multicenter retrospective cohort study. Consecutive patients that underwent EUS-GJ using a FCSEMS for MALS between April 2017 and November 2022 were enrolled. Primary outcomes were technical and clinical success rates. Secondary outcomes were adverse events, recurrent symptoms, and overall survival. RESULTS: Twelve patients (median age: 67.5 years (interquartile range: 58-74.8); 50% male) were included. The most common primary disease and type of previous surgery were pancreatic cancer (67%) and pancreatoduodenectomy (75%), respectively. Technical success and clinical success were achieved in all patients. Procedure-related adverse events occurred in one patient (8%) with mild peritonitis. During a median follow-up of 96.5 days, one patient (8%) had recurrent symptoms due to the EUS-GJ stent dysfunction; including biliary events unrelated to the EUS-GJ stent, five patients (42%) had recurrent events. The median overall survival was 137 days. Nine patients (75%) died due to disease progression. CONCLUSIONS: EUS-GJ with a FCSEMS seems safe and effective for MALS with high technical and clinical success rates and an acceptable recurrence rate.

Rebamipide induces dendritic cell recruitment to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-exposed rat gastric mucosa based on IL-1ß upregulation.

Rebamipide is usually used for mucosal protection, healing of gastric ulcers, treatment of gastritis, etc., but its effects on gastric malignancy have not been elucidated. Using Lewis and Buffalo rat strains treated with peroral administration of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), we evaluated the effect of rebamipide on the induction of tumor-suppressive dendritic cells, which are known to be heterogeneous antigen-presenting cells of bone marrow origin and are critical for the initiation of primary T-cell responses. Using CD68 as a marker for dendritic cells, the stomach pyloric mucosae of Lewis and Buffalo rats were immunohistochemically analyzed in the presence or absence of rebamipide and MNNG. After a 14-day treatment of rebamipide alone, no significant change in number of CD68-expressing cells was detected in either rat strain. However, after concurrent exposure to MNNG for 14 days, treatment with rebamipide slightly increased CD68-positive cells in the Lewis strain, and significantly increased them in the Buffalo strain. Analysis of two chemotactic factors of dendritic cells, IL-1ß and TNF-α, in the gastric cancer cells showed that expression of IL-1ß, but not TNF-α, was induced by rebamipide in a dose-dependent manner. A luciferase promoter assay using gastric SH-10-TC cells demonstrated that an element mediating rebamipide action exists in the IL-1ß gene promoter region. In conclusion, rebamipide has potential tumor-suppressive effects on gastric tumorigenesis via the recruitment of dendritic cells, based on the upregulation of the IL-1ß gene in gastric epithelial cells.

Relationship between vomiting reflex during esophagogastroduodenoscopy and dyspepsia symptoms.

AIM: Although frequent vomiting reflexes during esophagogastroduodenoscopy (EGD) causes suffering in patients, very few studies have investigated the characteristics of subjects who frequently develop vomiting reflexes. This study examined the incidence of the vomiting reflex and related factors, especially upper gastrointestinal symptoms, among individuals undergoing transoral EGD. METHODS: Subjects included 488 consecutive adults (mean age, 56.1 ± 8.9 years) who underwent transoral EGD for gastric cancer screening between February 2010 and March 2011. All procedures were performed by an endoscopist with 15 years of experience. Based on a questionnaire survey using the frequency scale for the symptoms of gastroesophageal reflux disease (FSSG), symptoms (dyspepsia and acid reflux symptoms) and the number of vomiting reflexes during EGD were recorded. RESULTS: Of the 488 subjects, 271 (56%) developed vomiting reflexes (mean, 4.2 times). This reflex-positive group was younger (54.3 ± 9.5 years) than the reflex-negative group (58.3 ± 7.7 years, P < 0.001). The number of subjects in the reflex-positive group with a high FSSG dyspepsia score (2.27 ± 2.57 vs 1.23 ± 1.84; P < 0.001), acid reflux symptom score (1.96 ± 2.22 vs 1.34 ± 2.14; P < 0.01) or an esophageal hiatal hernia (14.8% vs 4.6%; P < 0.001) was significantly higher than in the reflex-negative group. Multivariate analysis also showed a significant correlation between these four factors and the occurrence of vomiting reflexes. Using an FSSG dyspepsia score of 1 as the cut-off offered 68% sensitivity and 57% specificity for predicting the occurrence of vomiting reflexes. CONCLUSION: Based on FSSG questionnaire responses on upper gastrointestinal symptoms, dyspepsia symptoms, in particular, are related to presence of vomiting reflexes during EGD.

Practical Tips for Safe and Successful Endoscopic Ultrasound-Guided Hepaticogastrostomy: A State-of-the-Art Technical Review.

Currently, endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is widely performed worldwide for various benign and malignant biliary diseases in cases of difficult or unsuccessful endoscopic transpapillary cholangiopancreatography (ERCP). Furthermore, its applicability as primary drainage has also been reported. Although recent advances in EUS systems and equipment have made EUS-HGS easier and safer, the risk of serious adverse events such as bile leak and stent migration still exists. Physicians and assistants need not only sufficient skills and experience in ERCP-related procedures and basic EUS-related procedures such as fine needle aspiration and pancreatic fluid collection drainage, but also knowledge and techniques specific to EUS-HGS. This technical review mainly focuses on EUS-HGS with self-expandable metal stents for unresectable malignant biliary obstruction and presents the latest and detailed tips for safe and successful performance of the technique.

The Feasibility of Whole-Liver Drainage with a Novel 8 mm Fully Covered Self-Expandable Metal Stent Possessing an Ultra-Slim Introducer for Malignant Hilar Biliary Obstructions.

BACKGROUND: In the case of an unresectable malignant hilar biliary obstruction (MHBO), the optimal drainage method has not yet been established. Recently, an 8 mm, fully covered, self-expandable metal stent (FCSEMS) with an ultra-slim introducer has become available. In this article, the results of whole-liver drainage tests using this novel FCSEMS for MHBO are reported. METHODS: Unresectable MHBOs up to Bismuth IIIa with strictures limited to the secondary branches were eligible. The proximal end of the stent was placed in such a way as to avoid blocking the side branches, and the distal end was placed above the papilla when possible. Consecutive patients treated between April 2017 and January 2021 were retrospectively analyzed. The technical and functional success rates, rates and causes of recurrent biliary obstruction (RBO), time to RBO (TRBO), revision for RBO, and adverse events (AEs) were evaluated. RESULTS: Eleven patients (Bismuth I/II/IIIa: 1/7/3) were enrolled. Two stents were placed in nine patients and three were placed in two patients. Both the technical and functional success rates were 100%. RBO occurred in four (36%) patients due to sludge formation. Revision was performed for three patients, with the successful removal of all stents. The median TRBO was 187 days, and no late AEs other than the RBO occurred. Regarding the distal position of the stent, the RBO rate was significantly lower (14.3% vs. 75%, p = 0.041) and the cumulative TRBO was significantly longer (median TRBO: not reached vs. 80 days, p = 0.031) in the case of the placement above the papilla than the placement across the papilla. CONCLUSION: For unresectable MHBOs of Bismuth I, II, and IIIa, whole-liver drainage with a novel 8 mm FCSEMS possessing an ultra-slim introducer was feasible and potentially safe, with favorable stent patency. Placement above the papilla might be preferrable to placement across the papilla.

Elevated risk of colorectal adenoma with Helicobacter pylori-related chronic gastritis: a population-based case-control study.

This study investigated correlations between Helicobacter pylori infection or chronic atrophic gastritis (CAG) and risk of colorectal adenoma in a population-based case-control study. Subjects comprised asymptomatic, middle-aged, male Japanese factory workers who participated in an annual health check-up program, including cancer screening with colonoscopy. We selected 239 colorectal adenoma cases based on histological evaluation and 239 age-matched adenoma-free controls, and evaluated colorectal adenoma risk according to stage of H. pylori-related chronic gastritis as determined by serum tests for H. pylori antibody titer and pepsinogen. Subjects with colorectal adenoma were more likely to be smokers and have hypercholesterolemia. H. pylori infection was a risk factor for adenoma as a whole (crude odds ratio [OR]: 2.26, 95% confidence interval [CI]: 1.44-3.55). Analysis of distal adenoma cases showed that adenoma risk was significantly increased in the presence of H. pylori infection, but there was no further increase in risk with CAG. In contrast, proximal adenoma risk increased stepwise with the presence and progression of H. pylori-related chronic gastritis and showed a maximal and significant increase with CAG (crude OR: 4.51, 95% CI: 1.43-14.2). Subjects with more extensive and severe gastritis showed still higher risk not only for proximal but also for distal adenoma. H. pylori-related chronic gastritis is likely to be involved in the development of colorectal neoplasms, and its progression appears to increase the risk, particularly for proximal adenomas. Knowing the H. pylori-related chronic gastritis stage will probably be useful for evaluation of risk for colorectal neoplasia.