Alcohol consumption, multiple Lugol-voiding lesions, and field cancerization

The development of multiple squamous cell carcinomas (SCC) in the upper aerodigestive tract, which includes the oral cavity, pharynx, larynx, and esophagus, is explained by field cancerization and is associated with alcohol consumption and cigarette smoking. We reviewed the association between alcohol consumption, multiple Lugol-voiding lesions, and field cancerization, mainly based on the Japan Esophageal Cohort study. The Japan Esophageal Cohort study is a prospective cohort study that enrolled patients with esophageal SCC after endoscopic resection. Enrolled patients received surveillance by gastrointestinal endoscopy every 6 months and surveillance by an otolaryngologist every 12 months. The Japan Esophageal Cohort study showed that esophageal SCC and head and neck SCC that developed after endoscopic resection for esophageal SCC were associated with genetic polymorphisms related to alcohol metabolism. They were also associated with Lugol-voiding lesions grade in the background esophageal mucosa, the score of the health risk appraisal model for predicting the risk of esophageal SCC, macrocytosis, and score on alcohol use disorders identification test. The standardized incidence ratio of head and neck SCC in patients with esophageal SCC after endoscopic resection was extremely high compared to the general population. Drinking and smoking cessation is strongly recommended to reduce the risk of metachronous esophageal SCC after treatment of esophageal SCC. Risk factors for field cancerization provide opportunities for early diagnosis and minimally invasive treatment. Lifestyle guidance of alcohol consumption and cigarette smoking for esophageal precancerous conditions, which are endoscopically visualized as multiple Lugol-voiding lesions, may play a pivotal role in decreasing the incidence and mortality of esophageal SCC.

Endoscopic and Histological Gastritis in University Students with Helicobacter pylori Infection

Objective Although the characteristics of Helicobacter pylori infection have been extensively reported, there is a lack of consensus regarding its characteristics in young adults. The present study examined the endoscopic and histological characteristics of young adults who underwent eradication therapy for H. pylori infection. Methods We examined the H. pylori infection status of first-year students at Okayama University School of Medicine and Dentistry between 2014 and 2020. A total of 152 (6.8%) students who were positive for H. pylori antibody or pepsinogen tests were enrolled in the study. Among them, 107 students underwent endoscopy, and their biopsy samples were investigated. Seventy-five students were diagnosed with H. pylori infections. Results Of 75 H. pylori-positive patients, 57 (76.0%) had endoscopic atrophic gastritis, and 42 (56.0%) had histological atrophy. A few patients had severe atrophic gastritis. All 65 patients who underwent an eradication assessment were successfully treated. After successful eradication, 26 patients underwent endoscopic follow-up. The mean follow-up period was 32.9 months. A histological evaluation revealed that gastric antrum atrophy had subsided in 11 of 14 patients, and atrophy in the lesser curvature of the gastric body had subsided in 7 of 8 patients. Conclusion More than half of young adults with H. pylori infection had atrophic gastritis. We found mild atrophy in young adults, which subsided shortly after eradication treatment. This study provides a foundation for future studies to evaluate the validity of eradication therapy in preventing gastric cancer in patients.

Innovative submucosal injection solution for endoscopic resection with phosphorylated pullulan: A preclinical study

BACKGROUND AND AIMS

The submucosal injection solution is used to assist in endoscopic surgery. The high viscosity of current solutions makes it difficult to inject. In the present study, we developed an extremely low-viscosity, easy-to-use submucosal injection solution using phosphorylated pullulan (PPL).

METHODS

The PPL solutions were prepared at different concentrations, and their viscosity was measured. The mucosal elevation capacity was evaluated using excised porcine stomachs. Controls included 0.4% sodium hyaluronate (SH), 0.6% sodium alginate (SA), and saline. To evaluate the practicality, the catheter injectability of 0.7% PPL was measured, and endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) were performed using the stomach and colorectum of live pigs. As controls, 0.4% SH and saline were used.

RESULTS

The PPL solutions were of extremely low viscosity compared to those of 0.4% SH and 0.6% SA. Nevertheless, the mucosal elevation capacity of PPL solutions for up to 0.7% concentration was similar to that of 0.4% SH, and 0.7% PPL was less resistant to catheter infusion than 0.4% SH and 0.6% SA. In live pig experiments with EMR and ESD, snaring after submucosal injection of 0.7 % PPL was easier than with 0.4% SH, and ESD with 0.7% PPL produced less bubble formation than with 0.4% SH, and the procedure time tended to be shorter with 0.7% PPL than with 0.4% SH because of the shorter injection time.

CONCLUSIONS

The PPL solution is an innovative and easy-to-use submucosal injection solution.

Clinical significance of gastrointestinal bleeding history in patients who undergo left atrial appendage closure

Background and Aim

Anticoagulant users with nonvalvular atrial fibrillation (NVAF) sometimes suffer from gastrointestinal bleeding (GIB) and have difficulty continuing the medication. Left atrial appendage closure (LAAC) has been developed for such situations. We aimed to clarify the clinical significance of a history of GIB in comparison to other factors in patients who had undergone LAAC.

Methods

From October 2019 to September 2023, patients with NVAF who underwent LAAC at our hospital were enrolled. We investigated the percentage of patients with a history of GIB who underwent LAAC and compared the incidence of post-LAAC bleeding in these patients compared to those with other factors.

Results

A total of 45 patients were included. There were 19 patients (42%) with a history of GIB who underwent LAAC. In a Kaplan-Meier analysis, the cumulative incidence of bleeding complications after LAAC was significantly higher in patients with a history of GIB in comparison to patients with other factors. There were eight cases of post-LAAC bleeding in total, and seven cases had GIB.

Conclusions

We need to recognize that GIB is a significant complication in patients who undergo LAAC. The management of GIB by gastroenterologists is essential to the success of LAAC.

A Case of Gastric Mucosa-associated Lymphoid Tissue Lymphoma that Relapsed after 11 Years Subsequent to Achieving Complete Remission

A 38-year-old Japanese man was diagnosed with extranodal marginal zone lymphoma of the mucosa-associated lymphoid tissue in the stomach (gastric MALT lymphoma). Fluorescence in situ hybridization analysis revealed the absence of t (11;18) (q21;q21) translocation but the presence of extra copies of MALT1, indicating tetrasomy 18. Helicobacter pylori eradication led to complete remission (CR). However, the gastric MALT lymphoma relapsed after 11 years old. This case underscores the need for long-term observation (>10 years) of patients with gastric MALT lymphoma. Further investigation is warranted to elucidate the correlation between trisomy/tetrasomy 18 and the recurrence propensity.

Metachronous primary gastric cancer after endoscopic resection in patients with esophageal squamous cell carcinoma

BACKGROUND

This study aimed to evaluate the risk factors for developing metachronous primary Gastric Cancer (GC) after Endoscopic Resection (ER) for esophageal Squamous Cell Carcinoma (SCC).

METHODS

We studied 283 patients with esophageal SCC who underwent ER. The study outcomes were as follows: (1) incidence of metachronous primary GC after ER; and (2) predictors for the development of metachronous primary GC after ER by the Cox proportional hazards model.

RESULTS

The median follow-up was 43.1 months (1.81-79.1), and the 3-year cumulative incidence of metachronous primary GC was 6.5% (95%CI: 4.1-10.4). The incidence of metachronous primary GC during the follow-up period was 2.31 per 100 person-years. The frequencies of severe gastric atrophy and macrocytosis at the timing of ER were significantly higher in patients with than without metachronous primary GC (91.7% vs. 73.2%, p = 0.0422, 20.8% vs. 5.2%, p = 0.0046, respectively). Severe gastric atrophy was associated with the development of metachronous primary GC (sex-and-age adjusted hazard ratio (HR) [95%CI] = 4.12 [0.95-27.78], p = 0.0093). Macrocytosis was associated with the development of metachronous primary GC (sex-and-age adjusted HR = 4.76 [1.75-13.0], p = 0.0012) and found to be an independent predictor for metachronous primary GC by multivariate Cox proportional hazards analysis (HR [95%CI] = 4.35 [1.60-11.84], p = 0.004).

CONCLUSIONS

Severe gastric atrophy and macrocytosis should be noted in the development of metachronous primary GC after ER for esophageal SCC. In particular, macrocytosis at the timing of ER was considered an important predictor.

CLINICAL TRIALS REGISTRY NUMBER

UMIN000001676.

Optimal Bowel Preparation Method to Visualize the Distal Ileum via Small Bowel Capsule Endoscopy

Small bowel capsule endoscopy (SBCE) is a convenient and minimally invasive method widely used to evaluate the small intestine. However, especially in the distal ileum, visualization of the intestinal mucosa is frequently hampered by the remaining intestinal contents, making it difficult to detect critical lesions. Although several studies have reported on the efficacy of bowel preparation before SBCE, no standardized protocol has been established. Herein, we determined the optimal preparation method for better visualization of the distal ileum using SBCE. We retrospectively analyzed 259 consecutive patients who had undergone SBCE between July 2009 and December 2019, divided into three groups: Group A (no preparation except overnight fasting), Group B (ingestion of 1-2 L polyethylene glycol 4 h before colonoscopy after overnight fasting and performing SBCE immediately after colonoscopy), and Group C (ingestion of 0.9 L magnesium citrate [MC] before SBCE after overnight fasting). The visibility of the intestinal mucosa in the first 10 min and at the last 10 min during the period of observation of the distal ileum was examined using a scoring system and compared. The visibility of the images captured by SBCE was assessed based on the scoring of the degree of bile/chyme staining, residual fluid and debris, brightness, bubble reduction, and visualized mucosa. The status of intestinal collapse was also assessed. In the first 10 min of observation of the distal ileum, no significant differences were detected among the groups. In the last 10 min, significantly better images were acquired in Group C in terms of bile/chyme staining, brightness, bubble reduction, and visualized mucosa. Bowel preparation using a low-dose MC solution 2 h before SBCE provided significantly higher-quality images of the distal ileum. Further optimization, such as the timing of initiating the preparation, is necessary to determine the optimal regimen for bowel preparation prior to SBCE.

Idiopathic Gastric Antral Ulcers

A Japanese woman presented with gastric antral ulcers accompanied by erosion and edema, demonstrating a chronic pattern of improvement and recurrence for more than six years. The patient had no relevant treatment history, and Helicobacter pylori infection was ruled out. Other potential etiologies contributing to gastric ulcers were eliminated on the basis of endoscopic biopsy and blood laboratory findings. Consequently, the patient was diagnosed with idiopathic gastric antral ulcer. This disease is often overlooked, and the chronological endoscopic images provided in this report can be used as a reference.

A Case of Early Barrett's Adenocarcinoma With Eosinophilic Esophagitis

A 61-year-old man presented with epigastric pain and underwent upper gastrointestinal endoscopy. A strongly erythematous area was found in the short segment of the Barrett's esophagus, and a biopsy revealed well-differentiated adenocarcinoma. Linear furrows were observed in the lower esophagus, and a biopsy of the lesion revealed eosinophil infiltration of 30 eosinophils per high-power field. Therefore, a diagnosis of Barrett's adenocarcinoma with eosinophilic esophagitis was made. Although rare, the incidence of Barrett's adenocarcinoma and eosinophilic esophagitis has been increasing in Japan in recent years, and the number of cases may increase in the future.

Endoscopic features of gastric neuroendocrine carcinoma

BACKGROUND AND AIM

The endoscopic features of gastric neuroendocrine carcinoma (G-NEC) have not been clarified; therefore, they were investigated in relation to clinicopathological findings.

METHODS

Consecutive patients with G-NECs who had undergone endoscopic or surgical resection at our institution between January 2005 and March 2022 were included in this retrospective study. The endoscopic and clinicopathological findings of the lesions were analyzed to provide information of diagnostic value. In addition, cases of gastric neuroendocrine tumor (G-NET) and common-type gastric adenocarcinoma treated in the same study period were identified to compare the endoscopic findings between each G-NEC versus G-NET, and G-NEC versus common-type gastric adenocarcinoma. Patients with common-type gastric adenocarcinoma were matched for age, sex, tumor size, and depth of tumor invasion in 1:3 ratio.

RESULTS

Among 15 patients with 15 G-NECs, submucosal tumor-like marginal elevation (87%), adherent white coat (67%), and ulceration with a distinct border (60%) were characteristic endoscopic findings in white-light images. Magnifying narrow-band imaging endoscopy revealed an absent microsurface (MS) pattern plus disrupted irregular microvessel (MV) in five (71%) of seven cases with evaluable MS and MV patterns. The area with an absent MS pattern plus disrupted irregular MV corresponded to the histological finding of NEC component in all five cases. These endoscopic features were all significantly more frequent in G-NECs than G-NETs (n = 22) or common-type gastric adenocarcinomas (n = 45).

CONCLUSIONS

These endoscopic features should be taken into consideration to increase the index of suspicion and to improve the accuracy of target biopsies for G-NEC.

Risk factors for the development of second primary esophageal squamous-cell carcinoma after endoscopic resection for esophageal squamous-cell carcinoma according to genetic polymorphisms related to alcohol and nicotine metabolism

BACKGROUND

Multiple development of esophageal squamous-cell carcinoma is explained by field cancerization and is associated with alcohol consumption and smoking. We investigated the association between the development of second primary esophageal squamous-cell carcinoma after endoscopic resection for esophageal squamous-cell carcinoma and genetic polymorphisms related to alcohol and nicotine metabolism.

METHODS

The study group comprised 56 patients with esophageal squamous-cell carcinoma after endoscopic resection. The main variables were the following: (i) cumulative incidence and total number of second primary esophageal squamous-cell carcinoma according to genetic polymorphisms in alcohol dehydrogenase 1B, aldehyde dehydrogenase 2 and cytochrome P450 2A6; and (ii) risk factors of second primary esophageal squamous-cell carcinoma identified using a multivariate Cox proportional-hazards model. The frequencies of alcohol dehydrogenase 1B, aldehyde dehydrogenase 2 and cytochrome P450 2A6 genetic polymorphisms in the buccal mucosa were analyzed.

RESULTS

The median follow-up was 92.8 months (range: 2.7-134.2). Slow-metabolizing alcohol dehydrogenase 1B was associated with a higher 7-year cumulative incidence of second primary esophageal squamous-cell carcinoma (fast-metabolizing alcohol dehydrogenase 1B vs slow-metabolizing alcohol dehydrogenase 1B: 20.5% vs 71.4%, P = 0.006). Slow-metabolizing alcohol dehydrogenase 1B (relative risk [95% confidence interval]: 3.17 [1.49-6.73]), inactive aldehyde dehydrogenase 2 (2.17 [1.01-4.63]) and poorly-metabolizing cytochrome P450 2A6 (4.63 [1.74-12.33]) had a significantly higher total number of second primary esophageal squamous-cell carcinoma per 100 person-years. In the multivariate Cox proportional-hazards model, slow-metabolizing alcohol dehydrogenase 1B was a significant risk factor of the development of second primary esophageal squamous-cell carcinoma (hazard ratio 9.92, 95% confidence interval: 2.35-41.98, P = 0.0018).

CONCLUSIONS

Slow-metabolizing alcohol dehydrogenase 1B may be a significant risk factor for the development of second primary esophageal squamous-cell carcinoma. In addition, inactive aldehyde dehydrogenase 2 and poorly-metabolizing cytochrome P450 2A6 may be important factors.

Review of oral and pharyngolaryngeal benign lesions detected during esophagogastroduodenoscopy

Recent advancements in endoscopy equipment have facilitated endoscopists’ detection of neoplasms in the oral cavity and pharyngolaryngeal regions. In particular, image-enhanced endoscopy using narrow band imaging or blue laser imaging play an integral role in the endoscopic diagnosis of oral and pharyngolaryngeal cancers. Despite these advancements, limited studies have focused on benign lesions that can be observed during esophagogastroduodenoscopy in the oral and pharyngolaryngeal regions. Therefore, this mini-review aimed to provide essential information on such benign lesions, along with representative endoscopic images of dental caries, cleft palate, palatal torus, bifid uvula, compression by cervical osteophytes, tonsil hyperplasia, black hairy tongue, oral candidiasis, oral and pharyngolaryngeal ulcers, pharyngeal melanosis, oral tattoos associated with dental alloys, retention cysts, papilloma, radiation-induced changes, skin flaps, vocal cord paresis, and vocal fold leukoplakia. Whilst it is imperative to seek consultation from otolaryngologists or dentists in instances where the diagnosis cannot be definitively ascertained by endoscopists, the merits of attaining foundational expertise pertaining to oral and pharyngolaryngeal lesions are unequivocal. This article will be a valuable resource for endoscopists seeking to enhance their understanding of oral and pharyngolaryngeal lesions.

Degree of pharyngeal deformation caused by pharyngeal endoscopic submucosal dissection is associated with the incidence of aspiration pneumonia

Background and study aims  Endoscopic submucosal dissection (ESD) is one of the most minimally invasive treatments for superficial squamous cell cancer of the pharynx. However, aspiration pneumonia (AsP) associated with postoperative deformity of the pharynx may occur. The purpose of this study was to investigate the frequency of AsP and the degree of pharyngeal deformity after pharyngeal ESD. Patients and methods  This was a retrospective observational study of patients who underwent pharyngeal ESD at Okayama University Hospital between 2006 and 2017. The degree of pharyngeal deformation was assessed using the pharyngeal deformation grade (PDG). The primary endpoint was the frequency of AsP as a long-term adverse event. Results  Among the 52 patients enrolled, nine developed aspiration pneumonia, with a 3-year cumulative incidence of 9.0 % (95 % confidence interval [CI], 3.3 %-22.0 %). There were 16, 18, 16, and two patients that had PDG 0, 1, 2, and 3, respectively. Patients with a history of radiotherapy, as a treatment of head and neck cancer (44.4 % vs. 11.6 %; P  = 0.02) and the high PDG group (PDG 2 and 3) (77.8 % vs. 25.6 %; P  = 0.005) had a significantly higher incidence of AsP. The 3-year cumulative incidence rate of AsP after ESD in the high PDG group was significantly higher than that in the low PDG group (PDG 0 and 1) (23.9 % [95 %CI, 9.2.-49.5%] vs. 0 %; P  = 0.03). Conclusions  The incidence of aspiration pneumonia in the long-term course after pharyngeal ESD was revealed. The incidence of aspiration pneumonia may be associated with pharyngeal deformity, but further studies are needed.

Erratum: Differences in color between early gastric cancer and cancer-suspected non-cancerous mucosa on linked color imaging

[This corrects the article DOI: 10.1055/a-1989-6643.].

Scattered Tiny Whitish Protrusions in the Stomach Are a Clue to the Diagnosis of Autoimmune Gastritis

Herein, we report two patients with autoimmune gastritis who had undergone multiple esophagogastroduodenoscopy procedures for 17 and 9 years, respectively, before their diagnosis. Instead, they had been diagnosed with and treated for Helicobacter pylori-associated gastritis. The correct diagnosis was made when scatterings of tiny whitish protrusions in the gastric mucosa were detected on esophagogastroduodenoscopy. Our findings suggest that scattered tiny whitish bumps may be a clue to the diagnosis of autoimmune gastritis.

Long-term Survival After Endoscopic Resection For Gastric Cancer: Real-world Evidence From a Multicenter Prospective Cohort

BACKGROUND & AIMS

We aimed to clarify the long-term outcomes of endoscopic resection (ER) for early gastric cancers (EGCs) based on pathological curability in a multicenter prospective cohort study.

METHODS

We analyzed the long-term outcomes of 9054 patients with 10,021 EGCs undergoing ER between July 2010 and June 2012. Primary endpoint was the 5-year overall survival (OS). The hazard ratio for all-cause mortality was calculated using the Cox proportional hazards model. We also compared the 5-year OS with the expected one calculated for the surgically resected patients with EGC. If the lower limit of the 95% confidence interval (CI) of the 5-year OS exceeded the expected 5-year OS minus a margin of 5% (threshold 5-year OS), ER was considered to be effective. Pathological curability was categorized into en bloc resection, negative margins, and negative lymphovascular invasion: differentiated-type, pT1a, ulcer negative, ≤2 cm (Category A1); differentiated-type, pT1a, ulcer negative, >2 cm or ulcer positive, ≤3 cm (Category A2); undifferentiated-type, pT1a, ulcer negative, ≤2 cm (Category A3); differentiated-type, pT1b (SM1), ≤3 cm (Category B); or noncurative resections (Category C).

RESULTS

Overall, the 5-year OS was 89.0% (95% CI, 88.3%-89.6%). In a multivariate analysis, no significant differences were observed when the hazard ratio of Categories A2, A3, and B were compared with that of A1. In all the pathological curability categories, the lower limit of the 95% CI for the 5-year OS exceeded the threshold 5-year OS.

CONCLUSION

ER can be recommended as a standard treatment for patients with EGCs fulfilling Category A2, A3, and B, as well as A1 (UMIN Clinical Trial Registry, UMIN000005871).

Differences in color between early gastric cancer and cancer-suspected non-cancerous mucosa on linked color imaging

Background and study aims  Linked color imaging (LCI) can enhance the original color of each area and may useful to detect tumorous lesions during esophagogastroduodenoscopy. However, LCI may also enhance cancer-suspected non-cancerous regional color change. We conducted a retrospective image analysis to investigate the color characteristics of early gastric cancer (EGC) and cancer-suspected non-cancerous mucosa (CSM) in LCI. Methods  LCI images of both EGC and CSM were retrospectively collected from the database of the institution. Fifteen endoscopists individually judged each image as EGC or CSM. The color difference between the inside and outside of the lesions was measured by CIE-Lab analysis in both groups and compared. Results  A total of 245 LCI images of EGC (169) and CSM (76) were extracted and randomly lined for image collection. The test by the endoscopists showed accuracy, sensitivity, and specificity of 64.0 %, 63.7 %, and 64.0 %, respectively. Although the color difference between EGC and CSM was almost the same (12.5 vs. 12.9, not significant), each parameter of ΔL (bright: -0.3 vs. -2.7, P  < 0.001), Δa (Reddish: 7.2 vs. 9.6, P  = 0.004), and Δb (Yellowish: 6.4 vs. 3.8, P  < 0.001) was significantly different in the groups. The color feature of both positive ΔL and Δb to EGC showed accuracy, sensitivity, and specificity of 54.7 %, 39.6 %, 88.2%, respectively. Conclusions  The total color difference was almost the same between EGC and CSM; however, their color tones were different on linked color imaging. Although the color characteristics of EGC had high specificity, they also had low sensitivity.

Endoscopic findings of gastric neoplasms in familial adenomatous polyposis are associated with the phenotypic variations and grades of dysplasia

Patients with familial adenomatous polyposis (FAP) are at increased risk of developing gastric neoplasms. However, endoscopic findings have not been sufficiently investigated. We investigated the phenotypic expression of gastric adenoma (low-grade dysplasia) and gastric cancer (high-grade dysplasia or carcinoma) in patients with FAP and clarified their relationships to endoscopic findings. Of 29 patients with FAP who underwent esophagogastroduodenoscopy between 2005 and 2020, 11 (38%) had histologically confirmed gastric neoplasms, including 23 lesions of gastric adenoma and 9 lesions of gastric cancer. The gastric neoplasms were classified into 3 phenotypes (gastric, mixed, or intestinal type) according to the immunostaining results and evaluated for location (U or M region: upper or middle third of the stomach or L region: lower third of the stomach), color (same as the background mucosa, whitish, or reddish), macroscopic type (elevated, flat, or depressed), background mucosal atrophy (present or absent), fundic gland polyps in the surrounding mucosa (present or absent), and morphologic changes in tumor size. Elevated whitish gastric adenomas were further subdivided by macroscopic type (flat elevated, protruded, or elevated with a central depression) and color (milky- or pinkish-white). The gastric adenomas included gastric (11/23, 48%), mixed (4/23, 17%), and intestinal (8/23, 35%) phenotypes. In contrast, no lesions of gastric cancers showed a gastric phenotype (0/9, 0%), while 5 (56%) and 4 (44%) lesions were intestinal and mixed phenotypes, respectively. Gastric cancers were significantly more likely than gastric adenomas to present as reddish depressed lesions with gastric atrophy. All gastric-type adenomas occurred in non-atrophic mucosa, in mucosa with fundic gland polyps in the periphery, in the U or M region, and as flat elevated or protruded lesions with a milky-white color. Half of the lesions increased in size. Meanwhile, the typical endoscopic features of intestinal-type adenomas included occurrence in the L region and elevated pinkish-white lesions with central depression. None of the intestinal-type adenomas increased in size during the observation period. We believe that these endoscopic features will be useful for the prompt diagnosis and appropriate management of gastric neoplasms in patients with FAP.

Postoperative Bleeding Risk after Gastric Endoscopic Submucosal Dissection in Patients Receiving a P2Y12 Receptor Antagonist

Background/Aims

The safety of gastric endoscopic submucosal dissection (ESD) in users of a P2Y12 receptor antagonist (P2Y12RA) under current guidelines has not been verified.

Methods

Patients treated by gastric ESD at Okayama University Hospital between January 2013 and December 2020 were registered. The postoperative bleeding rates of patients (group A) who did not receive any antithrombotic drugs; patients (group B) receiving aspirin or cilostazol monotherapy; and P2Y12RA users (group C) those on including monotherapy or dual antiplatelet therapy were compared. The risk factors for post-ESD bleeding were examined in a multivariate analysis of patient background, tumor factors, and antithrombotic drug management.

Results

Ultimately, 1,036 lesions (847 patients) were enrolled. The bleeding rates of group B and C were significantly higher than that of group A (p=0.012 and p<0.001, respectively), but there was no significant difference between group B and C (p=0.11). The postoperative bleeding rate was significantly higher in dual antiplatelet therapy than in P2Y12RA monotherapy (p=0.014). In multivariate analysis, tumor diameter ≥12 mm (odds ratio [OR], 4.30; 95% confidence interval [CI], 1.99 to 9.31), anticoagulant use (OR, 4.03; 95% CI, 1.64 to 9.86), and P2Y12RA use (OR, 3.40; 95% CI, 1.07 to 10.70) were significant risk factors for postoperative bleeding.

Conclusions

P2Y12RA use is a risk factor for postoperative bleeding in patients who undergo ESD even if receiving drug management according to guidelines. Dual antiplatelet therapy carries a higher risk of bleeding than monotherapy.

Site-specific differences in T lymphocyte composition of the gastric mucosa after Helicobacter pylori eradication

In our earlier work, we revealed that inflammation of the lesser curvature of the gastric body and antrum could constitute independent risk factors for gastric cancer development, while inflammation of the greater curvature was not. The aims of this study were as follows: first, to reveal the differences between T lymphocyte populations of the gastric antrum and the greater and lesser curvatures of the gastric body in patients after Helicobacter pylori eradication; second, to analyze the correlation between the composition of the stomach-resident T lymphocytes and time from H. pylori eradication; and third, to evaluate the sex differences in T lymphocyte subsets after H. pylori eradication. To investigate site-specific differences in stomach-resident T lymphocytes after H. pylori eradication, we performed flow cytometry analysis on samples taken from the gastric antrum, greater curvature of the gastric body, and lesser curvature of the gastric body of 20 patients. We also analyzed the correlation between the composition of the stomach-resident T lymphocytes and the time from H. pylori eradication. The lymphocyte subsets of the antrum and lesser curvature of the body were similar. In contrast, compared to those in the greater curvature of the gastric body, CD4+/CD3+ lymphocyte subsets (43.8 ± 19.4% vs 31.7 ± 14.6%) were elevated in the lesser curvature of the body, whereas CD8+/CD3+ (67.1 ± 21.3% vs 80.4 ± 12.0%), CD7+/CD3+ (91.2 ± 4.6% vs 93.7 ± 3.8%), CCR4+/CD3+ (7.7 ± 8.1% vs 10.4 ± 7.0%), CD45RA+/CD3+CD4+ (27.2 ± 24.8% vs 39.5 ± 20.8%), and CD45RA+/CD3+CD4- (14.2 ± 11.1% vs 18.7 ± 11.5) were lower. Linear regression analysis showed a negative correlation between the time after H. pylori eradication and CD4+/CD3+ (P < .05, R2 = 0.198). There were no significant differences between men and women with respect to the lymphocyte populations. These results indicate that there are site-specific differences in lymphocyte composition in the stomach after H. pylori eradication.

The diagnostic ability to classify neoplasias occurring in inflammatory bowel disease by artificial intelligence and endoscopists: A pilot study

BACKGROUND AND AIM

Although endoscopic resection with careful surveillance instead of total proctocolectomy become to be permitted for visible low-grade dysplasia, it is unclear how accurately endoscopists can differentiate these lesions, as classifying neoplasias occurring in inflammatory bowel disease (IBDN) is exceedingly challenging due to background chronic inflammation. We evaluated a pilot model of an artificial intelligence (AI) system for classifying IBDN and compared it with the endoscopist's ability.

METHODS

This study used a deep convolutional neural network, the EfficientNet-B3. Among patients who underwent treatment for IBDN at two hospitals between 2003 and 2021, we selected 862 non-magnified endoscopic images from 99 IBDN lesions and utilized 6 375 352 images that were increased by data augmentation for the development of AI. We evaluated the diagnostic ability of AI using two classifications: the "adenocarcinoma/high-grade dysplasia" and "low-grade dysplasia/sporadic adenoma/normal mucosa" groups. We compared the diagnostic accuracy between AI and endoscopists (three non-experts and four experts) using 186 test set images.

RESULTS

The diagnostic ability of the experts/non-experts/AI for the two classifications in the test set images had a sensitivity of 60.5% (95% confidence interval [CI]: 54.5-66.3)/70.5% (95% CI: 63.8-76.6)/72.5% (95% CI: 60.4-82.5), specificity of 88.0% (95% CI: 84.7-90.8)/78.8% (95% CI: 74.3-83.1)/82.9% (95% CI: 74.8-89.2), and accuracy of 77.8% (95% CI: 74.7-80.8)/75.8% (95% CI: 72-79.3)/79.0% (95% CI: 72.5-84.6), respectively.

CONCLUSIONS

The diagnostic accuracy of the two classifications of IBDN was higher than that of the experts. Our AI system is valuable enough to contribute to the next generation of clinical practice.

Erratum: Prospective multicenter study of the efficacy and safety of cold forceps polypectomy for ≤ 6-mm non-ampullary duodenal low-grade adenomas

[This corrects the article DOI: 10.1055/a-1793-9439.].

Prospective multicenter study of the efficacy and safety of cold forceps polypectomy for ≤ 6-mm non-ampullary duodenal low-grade adenomas

Background and study aims  Because the endoscopic treatment for non-ampullary duodenal adenoma (NADA) has a non-negligible risk of adverse events (AEs), a safe and easy treatment for NADA is desirable. This was a multicenter prospective trial evaluating the efficacy and safety of cold forceps polypectomy (CFP) for diminutive NADAs. Patients and methods  This study was prospectively conducted at six general hospitals and one university hospital. The inclusion criteria were histologic and endoscopic diagnosis of low-grade NADA measuring ≤ 6 mm. A second endoscopy was scheduled for 1 month after CFP. After confirmation of the success of CFP, 6-month and 12-month surveillance endoscopies were scheduled. The primary endpoint was the endoscopic and histologic disease disappearance rates at the 12-month endoscopy. Results  Thirty-nine lesions from 38 patients were prospectively included. Median tumor size at enrollment was 5 mm (range 3-6 mm). There were four cases of remnant lesions at the second endoscopy, and the lesion disappearance rate of single CFP was 89.7 % (35 /39; 95 % confidence interval (CI), 76.9 %-97.9 %). In three cases, complete removal of the lesion was achieved with a single re-CFP, but one case required four repeat CFPs. The lesion disappearance rate at 12-month endoscopy was 97.4 % (38 /39; 95 %CI, 86.8 %-99.5 %). During the follow-up period, no AEs related to CFP were observed. Conclusions  CFP for NADA ≤ 6 mm was safe and effective in this study. This common endoscopic method to remove lesions may be an option for treatment of diminutive NADAs.

Linked Color Imaging (LCI) Emphasizes the Color Changes in the Gastric Mucosa After Helicobacter pylori Eradication

BACKGROUND

Diffuse redness is a characteristic endoscopic finding that indicates current infection of Helicobacter pylori, which is reduced after successful eradication. Linked color imaging (LCI) has been reported to improve the visibility of diffuse redness compared to white light imaging (WLI); however, quantitative evaluation has not been reported.

AIMS

This study aimed to objectively evaluate the color change of the gastric mucosa after H. pylori eradication.

METHODS

Images of the greater curvature of the antrum and corpus were captured, and the sites were biopsied during esophagogastroduodenoscopy (EGD) before and 1 year after eradication. The region of interest (ROI) was set around the biopsied area on the images. The color difference (ΔE) before and after eradication was calculated using the CIE L*a*b* color space. The association between the histological evaluation and the color value of the corresponding ROI was determined.

RESULTS

At the antrum, there was no significant color change with either mode. At the corpus, the a* value, which reflected redness, decreased significantly after eradication with both modes (WLI: 41.2 to 36.0, LCI: 37.5 to 25.5); the b* value, reflecting yellowish, decreased with WLI, but increased significantly with LCI (WLI: 44.6 to 41.6, LCI: 23.9 to 29.2). The ΔE was significantly larger with LCI than with WLI (16.5 vs. 8.6). The a* values at the corpus were generally associated with histological neutrophil infiltration.

CONCLUSIONS

Quantitative evaluation revealed that LCI emphasizes the change in color of the gastric mucosa due to the reduction in diffuse redness.

Application of convolutional neural networks for evaluating the depth of invasion of early gastric cancer based on endoscopic images

BACKGROUND AND AIM

Recently, artificial intelligence (AI) has been used in endoscopic examination and is expected to help in endoscopic diagnosis. We evaluated the feasibility of AI using convolutional neural network (CNN) systems for evaluating the depth of invasion of early gastric cancer (EGC), based on endoscopic images.

METHODS

This study used a deep CNN model, ResNet152. From patients who underwent treatment for EGC at our hospital between January 2012 and December 2016, we selected 100 consecutive patients with mucosal (M) cancers and 100 consecutive patients with cancers invading the submucosa (SM cancers). A total of 3508 non-magnifying endoscopic images of EGCs, including white-light imaging, linked color imaging, blue laser imaging-bright, and indigo-carmine dye contrast imaging, were included in this study. A total of 2288 images from 132 patients served as the development dataset, and 1220 images from 68 patients served as the testing dataset. Invasion depth was evaluated for each image and lesion. The majority vote was applied to lesion-based evaluation.

RESULTS

The sensitivity, specificity, and accuracy for diagnosing M cancer were 84.9% (95% confidence interval [CI] 82.3%-87.5%), 70.7% (95% CI 66.8%-74.6%), and 78.9% (95% CI 76.6%-81.2%), respectively, for image-based evaluation, and 85.3% (95% CI 73.4%-97.2%), 82.4% (95% CI 69.5%-95.2%), and 83.8% (95% CI 75.1%-92.6%), respectively, for lesion-based evaluation.

CONCLUSIONS

The application of AI using CNN to evaluate the depth of invasion of EGCs based on endoscopic images is feasible, and it is worth investing more effort to put this new technology into practical use.

[Zinc acetate-associated gastric lesions:a case report]

An 82-year-old Japanese man underwent esophagogastroduodenoscopy for postprandial epigastric discomfort. The patient was diagnosed with hypozincemia with a serum zinc level of 63μg/dL (normal range:80-130μg/dL), and he had commenced oral intake of zinc acetate 1 month before the esophagogastroduodenoscopy. Endoscopy showed erosions with white-coated mucosa surface adhesions and erythema on the lesser curvature of the gastric body. Moderately differentiated tubular adenocarcinoma was suspected based on the biopsy examination findings;therefore, he was referred to our hospital for further examination and treatment. A repeat endoscopy showed two erosions with white-coated mucosa surface adhesion and erythema on the lesser curvature of the gastric body. However, the lesion location was different from that detected in the initial endoscopy. The biopsy showed no neoplastic changes. Therefore, based on the endoscopic findings and history of oral zinc acetate administration, we diagnosed the gastric mucosal injury as zinc acetate-associated gastric lesions. The cessation of zinc acetate intake resulted in the resolution of gastric lesions. Reassessment of the biopsy specimen from the initial endoscopy revealed erosions, epithelial cells showing infarct-like necrosis, degenerative atypical cells, and necrotic substances, which were misdiagnosed as neoplastic changes. This case highlights the importance of recognizing the typical endoscopic features of a zinc acetate-associated gastric lesion to enable its prompt diagnosis during esophagogastroduodenoscopy.

Clinicopathological Characteristics of Superficial Barrett's Adenocarcinoma in a Japanese Population: A Retrospective, Multicenter Study

Objective Although Barrett's adenocarcinoma (BA) remains a minor disease in Japan, its incidence has been gradually increasing. We analyzed the characteristics of BA in Japanese populations. Methods We retrospectively reviewed medical records and analyzed the clinicopathological differences between short-segment Barrett's esophagus (SSBE) and long-segment Barrett's esophagus (LSBE), as well as metastasis. Local recurrence and metachronous lesions were analyzed only in patients who underwent endoscopic resection (ER). Patients Consecutive patients who had pathological T1 BAs resected by ER or surgery from January 2003 to December 2017. Results A total of 168 patients were analyzed, including 139 with SSBE and 29 with LSBE. In total, 67% of the SSBE lesions and 32% of the LSBE lesions were located between 0 and 3 o'clock (p=0.0014). No patients who achieved pathological margin-free resection (pR0) and 17% of patients who did not achieve pR0 experienced local recurrence (p=0.0131). None of the patients without lymphovascular involvement, a poorly differentiated component, lesion size of >30 mm, and submucosal invasion of >500 μm experienced metastasis. The 5-year cumulative incidence rate of metachronous BA after ER was 0% in patients with SSBE and 40% in patients with LSBE (p=0.0005). Conclusion Superficial BA was likely to be detected at the right anterior wall of SSBE in the Japanese population. The risk for metachronous BA after ER was high in Japanese patients with LSBE, as in Western patients.

Zinc Acetate Dihydrate Tablet-associated Gastric Lesions

Objective This study aimed to determine the prevalence and endoscopic features of zinc acetate dihydrate tablet-associated gastric lesions. Methods We retrospectively examined the endoscopic features of 47 patients taking zinc acetate dihydrate tablets who underwent esophagogastroduodenoscopy. Results Gastric mucosal alterations, including redness, erosions, ulcers, and adhesion of the white coat, were observed in 29 of 47 patients (61.7%). Among patients with gastric lesions (group A), there was a significantly higher percentage of symptomatic patients in comparison to patients without lesions (group B) (65.5% vs. 22.2%; p<0.01). The background characteristics of the two groups did not differ to a statistically significant extent. On esophagogastroduodenoscopy, mucosal redness (n=27, 93.1%), erosions (n=26, 90.0%), adhesion of the white coat (n=25, 86.2%), and ulcers (n=9, 31.0%) were observed. None of the 19 patients who previously underwent esophagogastroduodenoscopy had gastric lesions before starting zinc acetate dihydrate. Esophagogastroduodenoscopy was performed after the cessation of zinc acetate dihydrate intake in six patients, and revealed the resolution of gastric lesions. Conclusion Gastric lesions were observed in 29 of 47 patients who were taking zinc acetate dihydrate tablets. The most common endoscopic findings were mucosal redness (93.1%), erosions (90.0%), adhesion of the white coat (86.2%), and ulcers (31.0%). Although the exact pathogenesis is uncertain, we believe that understanding the unique manifestations of this gastric lesion will help physicians manage adverse events in patients taking zinc acetate dihydrate tablets.

Gastric Adenoma: A High Incidence Rate of Developing Carcinoma and Risk of Metachronous Gastric Cancer according to Long-Term Follow-Up

INTRODUCTION

Gastric adenomas are histologically defined as benign epithelial tumors. While some of them remain adenomas for a long time, others progress to carcinomas. However, long-term outcomes of such cases are not entirely clear. Here, we explored the risk factors and incidence of developing carcinoma from gastric adenoma as well as metachronous gastric cancer.

METHODS

This study was conducted at a facility that adopted a follow-up strategy for gastric adenoma. Lesions histologically diagnosed as gastric intestinal-type adenomas between January 2004 and December 2016 were analyzed. Clinicopathological data were collected from patients' medical records, and histological changes from adenoma to carcinoma during endoscopic follow-up and risk factors of cancer development were evaluated.

RESULTS

This study involved 409 lesions from 376 patients. The analysis of the development of gastric cancer from adenoma and metachronous gastric cancer was ultimately performed for 282 lesions from 258 patients and 269 lesions from 246 patients, respectively, due to different follow-up periods. The 5-year rate of carcinoma development was 34.0%. Risk factors for carcinoma development upon multivariate analysis were lesion size ≥15 mm and morphological depression. All cases with both factors developed gastric carcinoma, and 50.5% of those with either factor developed carcinoma within 5 years. Gastric adenoma was accompanied by metachronous gastric cancer in 1.5% of the patients annually. The only risk factor for metachronous gastric carcinoma was primary adenoma progressing to carcinoma during the follow-up period.

DISCUSSION/CONCLUSION

Given the high rate of carcinoma development in patients with risk factors, resection of gastric adenoma should be considered during the initial examination. Careful observation and follow-up should also be conducted to detect not only changes in the primary adenoma but also the occurrence of metachronous carcinoma, especially in cases of adenoma progressing to carcinoma.

Histologic Transformation from Follicular Lymphoma to Diffuse Large B-cell Lymphoma Detected during Colonoscopy

A 77-year-old Japanese woman who had been treated for follicular lymphoma for 8 years developed abdominal pain and intra-abdominal lymphadenopathies. Colonoscopy revealed an elevated lesion in the rectum, which presented as two humps with erosions. A diagnosis of histologic transformation of follicular lymphoma to diffuse large B-cell lymphoma was made by endoscopic biopsy. This case underscores the importance of endoscopy examinations and biopsy of newly emerged gastrointestinal lesions for the prompt diagnosis of histologic transformation, since salvage chemotherapy must be initiated quickly in such cases.

Scoring systems for differentiating gastrointestinal stromal tumors and schwannomas from leiomyomas in the stomach

There is no practical predictive model for the diagnosis of gastrointestinal stromal tumors (GISTs). To establish a practical predictive model for the diagnosis of subepithelial lesions in the stomach, we reviewed patients with GISTs (n = 89), schwannomas (n = 7), and leiomyomas (n = 28).The tumor was more frequently found along the gastric cardia in the leiomyoma group (57.1%) than in the GIST/schwannoma group (2.1%, P < .01). Contrast enhancement (57.3% vs 0%, P < .01) and intra-tumoral necrosis (34.4% vs 0.0%, P < .01) were more frequently observed in the GIST/schwannoma group than in the leiomyoma group. On endoscopic ultrasonography, 58.3% of GISTs/schwannomas showed uneven echogenicity, whereas the echogenicity was uneven in 21.4% of leiomyomas (P < .01). There were no differences between the tumor color and the presence or absence of ulcer formation, tumor bleeding, irregularity of the tumor margin, cystic spaces, and hyperechoic spots between the 2 groups. Based on these results, we developed a 2-step diagnostic algorithm for GISTs/schwannomas. The first step comprises 1 endoscopic feature: a cardiac or non-cardiac location. Tumors with a cardiac location were judged as leiomyomas and those with a non-cardiac location were judged as GISTs/schwannomas, with 96.9% sensitivity and 57.1% specificity for GIST/schwannoma diagnosis. The second step comprises a combination of endoscopic (non-cardiac location), radiologic (positive contrast enhancement and intra-tumoral necrosis), and endosonographic (uneven echogenicity) features for a total of 4 points. We assigned 1 point to each feature. Tumors with scores of 2 to 4 were judged as GISTs/schwannomas, with 81.3% sensitivity and 92.9% specificity for GIST/schwannoma diagnosis.Our predictive model will be a practical guide for the management of gastric subepithelial lesions.

Clinical characteristics and course of sporadic non-ampullary duodenal adenomas: A multicenter retrospective study

Sporadic non-ampullary duodenal adenoma (SNADA) is a rare disease, and therefore, its clinical characteristics have not been comprehensively investigated. Furthermore, owing to the high complication rates and severity of endoscopic resection, treatment strategies vary among facilities. In the present study, we aimed to clarify the clinical characteristics and course of SNADA.We extracted clinical and histological records of SNADA cases diagnosed in 11 hospitals between September 1999 and August 2014. The patients were divided into "no-resection" and "resection" groups based on the initial treatment approach. We investigated the long-term outcome of the "no-resection" group and treatment results of the "resection" group, with particular interest in endoscopic resection.Overall, 299 patients were diagnosed with SNADA. The median age at diagnosis was 67 years (range, 31-88 years), with approximately twice as many men as women. The median tumor size was 8.0 mm (2-60 mm). In total, 161 patients were initially selected for no-resection and 138 underwent resection. Age >70 years and the presence of either severe illness or poor performance status were significantly related to opting for no-resection. In the no-resection group, 101 patients underwent endoscopic follow-up for at least 1 year. During the observational period (2.5 ± 2.2 years), 27 lesions (27%) disappeared following cold forceps biopsy, and 13 lesions (14%) presented lateral growth. Four lesions (4%) changed to mucosal carcinoma, 3 were treated endoscopically, and 1 was surgically resected. Nineteen patients died; however, no one died of duodenal carcinoma. In the endoscopic resection group, en bloc resection was achieved in 78% of patients. However, the complication rate for perforation was 7%, and endoscopic submucosal dissection was associated with a 36% perforation rate.With the low incidence of cancer development and no disease specific death, the strategy of initially not performing resection could be considered especially for the older adults, poor-prognosis patients, or small lesions.

[Clinical characteristics of five patients with gastric emphysema]

Gastric emphysema is a rare condition in which gas from a nonbacterial source accumulates within the gastric wall. In this study, we retrospectively analyzed the cases of five patients who were diagnosed with gastric emphysema at the Okayama University Hospital between January 2010 and April 2021, to reveal the clinical features of the disease. Based on their reviews, we revealed that:i) gastric emphysema occurred in hospitalized bedridden patients (n=5), such as those during/after endotracheal intubation (n=3), those undergoing gastric tube placement (n=3), those undergoing percutaneous endoscopic gastrostomy (n=1), and those undergoing treatment for cerebral infarction (n=1);ii) gastric emphysema was accompanied by the accumulation of gas in the portal (n=4) or gastric veins (n=1);iii) gastric emphysema was accompanied by colon wall thickness increase (n=4);iv) esophagogastroduodenoscopy showed redness, erosions, coarse mucosa, and/or ulcers (n=5);v) a clear boundary between the damaged area and the intact mucosa was observed (n=5);vi) the anterior wall of the stomach was less affected (n=4);vii) mucosal damage was predominant in the gastric folds, whereas the furrow of the mucosa was less affected;and viii) treatment with enteral nutrition suspension and the administration of proton pump inhibitors and antibiotics resulted in the recovery of patients from gastric emphysema (n=5). These results indicate that patients with gastric emphysema have distinct clinical, endoscopic, and radiological features. Furthermore, our results show that these patients can be conservatively managed.

Clinical and phenotypical characteristics of submucosal invasive carcinoma in non-ampullary duodenal cancer

Objective

The rare incidence of submucosal invasive non-ampullary duodenal carcinoma has led to scant information in literature; therefore, we compared the clinicopathological features between submucosal invasive carcinoma (SM-Ca), mucosal carcinoma (M-Ca), and advanced carcinoma (Ad-Ca).

Materials

We retrospectively analyzed 165 patients with sporadic non-ampullary duodenal carcinomas (SNADCs) from four institutions between January 2003 and December 2018. The SNADCs were divided to three groups according to histological diagnosis: SM-Ca, M-Ca, and Ad-Ca. The clinicopathological characteristics and mucin phenotypes were compared between groups.

Results

Among the 165 SNADCs, 11 (7%) were classified as SM-Ca, 70 (42%) as M-Ca, and 84 (51%) as Ad-Ca. We found that all SM-Ca (P = 0.013) and most Ad-Ca (P = 0.020) lesions were located on the oral-Vater; however, an almost equal distribution of M-Ca lesions was found between the oral- and anal-Vater. No significant difference was observed between the tumor diameter of M-Ca and SM-Ca; however, 45% (5/11) of SM-Ca were ≤10 mm. A total of 73% (8/11) of SM-Ca were classified as gastric phenotype and no lesions were classified as intestinal phenotype; whereas most M-Ca were classified as intestinal phenotype (67%, 8/12).

Conclusions

SM-Ca lesions were all located on the oral-Vater and were highly associated with the gastric mucin phenotype, which were different from the features of most M-Ca.

Squamous Metaplasia of the Stomach Associated with Lymphoma Infiltration

We herein report a patient who presented with follicular lymphoma. Although the stomach was initially intact, mucosal redness and multiple erosions appeared in the gastric body owing to infiltration of the follicular lymphoma cells. Subsequently, a slightly depressed, white area lacking gastric mucosal structure was detected in the lesser curvature of the gastric cardia and body, where lymphoma cell infiltration was also pathologically observed beneath the stratified squamous epithelium. This case indicated that, although infrequent, prolonged mucosal injury owing to lymphoma infiltration can cause squamous metaplasia in the stomach.

Risk Factors for Gastric Cancer after the Eradication of Helicobacter pylori Evaluated Based on the Background Gastric Mucosa: A Propensity Score-matched Case-control Study

Objective The eradication of Helicobacter pylori (H. pylori) reduces the risk for gastric cancer (GC) development, but it cannot prevent GC completely. We investigated the risk factors of early GC development after the eradication of H. pylori, based on the histological characteristics of gastric mucosa. Methods Sixty-one patients who underwent endoscopic submucosal dissection for early GC after successful H. pylori eradication (Group A) and 122 patients without developing a gastric neoplasm over 3 years after successful H. pylori eradication (Group B) were analyzed. We compared the histological findings of the patients enrolled in Group A and Group B before and after the propensity score-matching. Results Comparing the characteristics of two the groups, Group A consisted predominantly of males, had significantly more elderly patients, and the years after successful eradication tended to be longer. We performed score matching for these three factors to reduce the influence of any confounding factors. After matching, the scores of inflammation for Group A (n=54) was significantly higher than those of Group B (n=54) at the greater curvature of the antrum, the lesser curvature of the corpus, and the greater curvature of the corpus. According to a multivariate analysis, inflammation of the greater curvature of the antrum and lesser curvature of the corpus were found to be independent risk factors. The risk ratio and 95% CI were 5.92 (2.11-16.6) (p<0.01), and 3.56 (1.05-13.2) (p=0.04), respectively. Conclusion A continuous high level of inflammation of the background gastric mucosa may be a risk factor for gastric cancer onset after H. pylori eradication.

Efficacy and safety of endoscopic submucosal dissection for gastric tube cancer: A multicenter retrospective study

BACKGROUND

Recent improvements in the prognosis of patients with esophageal cancer have led to the increased occurrence of gastric tube cancer (GTC) in the reconstructed gastric tube. However, there are few reports on the treatment results of endoscopic submucosal dissection (ESD) for GTC.

AIM

To evaluate the efficacy and safety of ESD for GTC after esophagectomy in a multicenter trial.

METHODS

We retrospectively investigated 48 GTC lesions in 38 consecutive patients with GTC in the reconstructed gastric tube after esophagectomy who had undergone ESD between January 2005 and December 2019 at 8 institutions participating in the Okayama Gut Study group. The clinical indications of ESD for early gastric cancer were similarly applied for GTC after esophagectomy. ESD specimens were evaluated in 2-mm slices according to the Japanese Classification of Gastric Carcinoma with curability assessments divided into curative and non-curative resection based on the Gastric Cancer Treatment Guidelines. Patient characteristics, treatment results, clinical course, and treatment outcomes were analyzed.

RESULTS

The median age of patients was 71.5 years (range, 57-84years), and there were 34 men and 4 women. The median observation period after ESD was 884 d (range, 8-4040 d). The median procedure time was 81 min (range, 29-334 min), the en bloc resection rate was 91.7% (44/48), and the curative resection rate was 79% (38/48). Complications during ESD were seen in 4% (2/48) of case, and those after ESD were seen in 10% (5/48) of case. The survival rate at 5 years was 59.5%. During the observation period after ESD, 10 patients died of other diseases. Although there were differences in the procedure time between institutions, a multivariate analysis showed that tumor size was the only factor associated with prolonged procedure time.

CONCLUSION

ESD for GTC after esophagectomy was shown to be safe and effective.

Reality of Gastric Cancer in Young Patients: The Importance and Difficulty of the Early Diagnosis, Prevention and Treatment

Gastric cancer usually arises in middle-aged to older patients, and is rarely found in younger patients. The clin-ical characteristics, etiology, prognosis, preventive methods and treatment of gastric cancer in young patients have not been fully investigated because of its low prevalence. In this review, we discuss the current under-standing and clinical problems associated with gastric cancer in young patients. Helicobacter pylori (H. pylori), which is a major cause of gastric cancer, especially in older populations, is closely associated with gastric cancer in young patients as well as in older patients. Gastric cancer in young patients tends to be diagnosed at an advanced stage with alarm symptoms. However, young patients with advanced gastric cancer tend to have a favorable general condition and organ function, so they can tolerate intensive systematic chemotherapy. Unfortunately, the prognosis of gastric cancer in young patients with an advanced stage is not favorable. We should not take this rare disease lightly, given its poor prognosis if patients are diagnosed at an unresectable stage. The evaluation of the H. pylori infection status and performance of H. pylori eradication therapy to prevent gastric cancer in young patients as well as the development of more intensive chemotherapy regimens for unre-sectable gastric cancer in young patients are warranted.

Four Cases of Desquamative Esophagitis Occurring after Hematopoietic Stem Cell Transplantation

We herein report four patients with desquamative esophagitis that developed one to nine days after peripheral blood stem cell transplantation (PBSCT). Three patients underwent allogeneic PBSCT for leukemia, and the other underwent autologous PBSCT for pineoblastoma. Esophagogastroduodenoscopy revealed mucosal sloughing and fresh blood in the esophagus. Fasting and intravenous proton pump inhibitor therapy in addition to blood transfusion improved the esophageal lesions within five to seven days in three patients. These cases indicate that desquamative esophagitis can occur in patients who receive hematopoietic stem cell transplantation. Although blood transfusions may be required, it can be resolved within seven days.

Continued Aspirin Treatment May Be a Risk Factor of Delayed Bleeding after Gastric Endoscopic Submucosal Dissection under Heparin Replacement: A Retrospective Multicenter Study

Objective Gastric endoscopic submucosal dissection (ESD) under heparin replacement (HR) of warfarin reportedly has a high risk of delayed bleeding (24-57%). It is possible that the delayed bleeding risk may have changed over the years. We evaluated the current risk of delayed bleeding after gastric ESD under HR of anticoagulant agents. Methods We retrospectively reviewed the delayed bleeding rate and analyzed the risk factors for delayed bleeding. Patients Consecutive patients who underwent gastric ESD under HR of anticoagulant agents from July 2015 to June 2017. Results A total of 32 patients with a solitary early gastric cancer and taking anticoagulant agents were analyzed, including 24 patients on warfarin (the warfarin group) and 8 patients on direct oral anticoagulants (the DOAC group). Three (9.4%) patients experienced delayed bleeding: three (12.5%) patients in the warfarin group and no patients in the DOAC group. Continued aspirin treatment was identified to be a risk factor of delayed bleeding (p=0.01). Conclusion Careful management may be required for patients undergoing gastric ESD under continued aspirin treatment in addition to HR of anticoagulant agents; although the delayed bleeding risk after gastric ESD under HR of anticoagulant agents might have decreased over the years.

The Color Difference between Differentiated Early Gastric Cancer and Suspicious Mucosal Areas on Linked Color Imaging

BACKGROUND

Image enhanced endoscopy (IEE) contributes to the early detection of gastrointestinal cancer. IEE enhances the color between a lesion and the background mucosa. Linked color imaging (LCI), a novel form of IEE, is a unique system for enhancing color and some studies have demonstrated the efficacy of LCI in the diagnosis of early gastric cancer (EGC) based on the color difference between cancer and the background mucosa. However, the effect may increase the area in which cancer is suspected and lead to an increase in false-positive results.

SUMMARY

We conducted a retrospective study of linked color images of differentiated EGC and suspicious mucosal areas to compare the colors between each lesion. Images of 38 EGCs and 23 suspicious areas were analyzed. The mean color values of EGC were as follows; L*(lightness), 61.7; a*(green to red), 41.2; and b*(blue to yellow), 27.1. Those of suspicious mucosal areas were as follows; L*, 56.1; a*, 44.2; and b*, 21.3. EGC had significantly higher L*, b* values and lower a* values in comparison to suspicious mucosal areas. EGC and suspicious mucosal areas had significantly higher a* values in comparison to the background mucosa. Key Messages: EGC had higher b* values in comparison to suspicious mucosal areas, and was not only reddish but also mixed with yellow, with an orange-like color.

Blue laser imaging and linked color imaging improve the color difference value and visibility of colorectal polyps in underwater conditions

BACKGROUND AND AIM

Underwater endoscopic mucosal resection (UEMR) has become widespread for treating colorectal polyps. However, which observational mode is best suited for determining polyp margins underwater remains unclear. To determine the best mode, we analyzed three imaging modes: white light imaging (WLI), blue laser imaging (BLI) and linked color imaging (LCI).

METHODS

Images of consecutive colorectal polyps previously examined by these three modes before UEMR were analyzed according to the degree of underwater turbidity (transparent or cloudy). Color differences between the polyps and their surroundings were calculated using the Commission Internationale d'Eclairage Lab color space in which 3-D color parameters were expressed. Eight evaluators, who were blinded to the histology, scored the visibility from one (undetectable) to four (easily detectable) in both underwater conditions. The color differences and visibility scores were compared.

RESULTS

Seventy-three polyps were evaluated. Sixty-one polyps (44 adenomatous, 17 serrated) were observed under transparent conditions, and 12 polyps (seven adenomatous, five serrated) were observed under cloudy conditions. Under transparent conditions, color differences for the BLI (8.5) and LCI (7.9) were significantly higher than that of WLI (5.7; P < 0.001). Visibility scores for BLI (3.6) and LCI (3.4) were also higher than that of WLI (3.1; P < 0.0001). Under cloudy conditions, visibility scores for LCI (2.9) and WLI (2.7) were significantly higher than that of BLI (2.2; P < 0.0001 and P = 0.04, respectively).

CONCLUSIONS

BLI and LCI were better observational modes in transparent water; however, BLI was unsuitable for cloudy conditions.

Clinical Questions and Answers on Gastrointestinal Endoscopy during the Novel Coronavirus Disease 2019 pandemic

Some situations may require endoscopy during the COVID-19 (Coronavirus Disease 2019) pandemic. Here, we describe the necessary precautions in the form of clinical questions and answers (Q&A) regarding the safe deployment of gastrointestinal endoscopy in such situations while protecting endoscopy staff and patients from infection. Non-urgent endoscopy should be postponed. The risk of infection in patients should be evaluated in advance by questionnaire and body temperature. The health of staff must be checked every day. Decisions to employ endoscopy should be based on the institutional conditions and aims of endoscopy. All endoscopic staff need to wear appropriate personal protective equipment (PPE). The endoscope and other devices should be cleaned and disinfected after procedures in accordance with the relevant guidelines. Optimal management of the endoscopy unit is required. Endoscopy for infected patients or those with suspected infection demands exceptional caution. When a patient who undergoes endoscopy is later found to have COVID-19, the members of staff involved are considered exposed to the virus and must not work for at least 14 days if their PPE is considered insufficient. When PPE resources are limited, some equipment may be used continuously throughout a shift as long as it is not contaminated. Details of the aforementioned protective measures are described.

Gastrointestinal endoscopy in the era of the acute pandemic of coronavirus disease 2019: Recommendations by Japan Gastroenterological Endoscopy Society (Issued on April 9th, 2020)

All gastrointestinal endoscopic procedures have a high risk of aerosol contamination of the coronavirus disease 2019 (COVID-19) to endoscopists, nurses, and healthcare assistants. Given the current pandemic situation of COVID-19, the Japan Gastroenterological Endoscopy Society issued the recommendation for gastrointestinal (GI) endoscopy based on the status of COVID-19 as of April 9, 2020, in Japan: (i) indications for GI endoscopy in the pandemic of COVID-19; (ii) practical protective equipment for medical personnel depending on the risk for COVID-19; (iii) preprocedural management, such as pharyngeal local anesthesia using lidocaine spray which has a potential to generate the aerosols; (iv) ideal settings of the endoscopy room including the numbers of the staff and the patients; (v) postprocedural management, such as undressing and follow-up of the patients, as well as the involved staff, were documented to fit the practical scenarios in GI endoscopy, with the available data in Japan and the world. We believe that certain measures will prevent further spread of COVID-19.

Clinical Characteristics and Risk Factors for Rebleeding in Patients with Obscure Gastrointestinal Bleeding

Objective With the advent of capsule endoscopy (CE) and double-balloon endoscopy (DBE), the diagnosis and treatment of obscure gastrointestinal bleeding (OGIB) have markedly progressed. However, rebleeding sometimes occurs and is difficult to diagnose and treat. The aim of the present study was to investigate the clinical features of OGIB and risk factors for rebleeding in our hospital. Methods A total of 195 patients who underwent CE and/or DBE for OGIB in our hospital from January 2009 to July 2016 were included in the present study. We analyzed 168 cases of small intestinal OGIB, after excluding 27 cases of extra small intestinal bleeding. The clinical characteristics and risk factors related to rebleeding were retrospectively studied. Results Among the 168 patients who were included in the analysis, 95 patients (56.5%) were male. The mean age was 64.5 years (range, 8 to 87 years). Hypertension (31.0%) was the most frequent comorbidity, followed by chronic kidney disease (19.0%). The final diagnoses were ulcerative lesions (n=50, 29.8%), vascular lesions (n=30, 17.9%), tumors (n=7, 4.2%), and diverticula (n=2, 1.2%). The bleeding source was undetermined in the remaining 79 cases (47.0%). Rebleeding was confirmed in 29 cases (17.3%). In a univariate analysis, chronic kidney disease, vascular lesions, and overt previous bleeding were significantly associated with the risk of rebleeding. A multivariate analysis showed that chronic kidney disease, vascular lesion, and overt previous bleeding were significantly associated with the risk of rebleeding. Conclusion Patients with OGIB with overt previous bleeding, vascular lesions, and/or chronic kidney disease had a higher risk of rebleeding.