Virtual indigo carmine chromoendoscopy images: A novel modality for peroral cholangioscopy using artificial intelligence technology (with video).

BACKGROUND AND AIMS: Accurately diagnosing biliary strictures is crucial for surgical decisions, and although peroral cholangioscopy (POCS) aids in visual diagnosis, diagnosing malignancies or determining lesion margins via this route remains challenging. Indigo carmine is commonly used to evaluate lesions during gastrointestinal endoscopy. We aimed to establish the utility of virtual indigo carmine chromoendoscopy (VICI) converted from POCS images using artificial intelligence. METHODS: This single-center, retrospective study analyzed 40 patients with biliary strictures who underwent POCS using white light imaging (WLI) and narrow-band imaging (NBI). A "cycle-consistent adversarial network" (CycleGAN) was used to convert the WLI into VICI of POCS images. Three experienced endoscopists evaluated WLI, NBI, and VICI via POCS in all patients. The primary outcome was the visualization quality of surface structures, surface microvessels, and lesion margins. The secondary outcome was diagnostic accuracy. RESULTS: VICI showed superior visualization of the surface structures and lesion margins compared with WLI (P<0.001) and NBI (P<0.001). The diagnostic accuracies were 72.5%, 87.5%, and 90.0% in WLI alone, WLI and VICI simultaneously, and WLI and NBI simultaneously, respectively. WLI and VICI simultaneously tended to result in higher accuracy than WLI alone (P=0.083) and the results were not significantly different from WLI and NBI simultaneously (P=0.65). CONCLUSIONS: VICI in POCS proved valuable for visualizing surface structures and lesion margins and contributed to higher diagnostic accuracy comparable to NBI. In addition to NBI, VICI may be a novel supportive modality for POCS.

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.

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.

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

BACKGROUND AND AIMS: A submucosal injection solution is used to assist in endoscopic surgery. The high viscosity of current solutions makes them 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 viscosities were 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 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 the solutions 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 endoscopic mucosal resection and ESD, snaring after submucosal injection of 0.7% PPL was easier than with 0.4% SH, 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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Efficacy and Safety of a Novel Hemostatic Peptide Solution During Endoscopic Submucosal Dissection: A Multicenter Randomized Controlled Trial.

INTRODUCTION: To compare the effectiveness of the novel hemostatic peptide, TDM-621, with that of conventional hemostatic methods in treating intraoperative blood oozing during endoscopic submucosal dissection (ESD). METHODS: This multicenter, open-label, randomized controlled trial involved 227 patients with gastric and rectal epithelial tumors in whom ESD was indicated. Patients in whom the source of blood oozing was difficult to identify with waterjet washing during the procedure and required hemostasis with hemostatic forceps were randomly assigned to the TDM-621 and control groups. The TDM-621 group (in which hemostasis was achieved with TDM-621, followed by coagulation hemostasis with hemostatic forceps, as needed) was compared with the control group (in which hemostasis was achieved with hemostatic forceps). The primary end point was the mean number of coagulations with hemostatic forceps, determined by a blinded independent review committee. The secondary end points were the rate of achievement of hemostasis with only TDM-621, the dosage of TDM-621, and adverse events in the TDM-621 group. RESULTS: The mean number of coagulations with hemostatic forceps was significantly reduced in the TDM-621 group (1.0 ± 1.4) compared with that in the control group (4.9 ± 5.2) ( P < 0.001). The rate of hemostasis achievement with only TDM-621 was 62.2%; the mean dosage of TDM-621 was 1.75 ± 2.14 mL. The rates of grade ≥3 adverse events were 6.2% and 5.0% in the TDM-621 and control groups, respectively. DISCUSSION: TDM-621 is a useful, easily operable hemostatic peptide for treatment of blood oozing during gastric and rectal ESD, with no serious safety concerns.

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).