Helicobacter pylori infection associated DNA methylation in primary gastric cancer significantly correlates with specific molecular and clinicopathological features.

Helicobacter pylori induces DNA methylation in gastric mucosa, which links to gastric cancer (GC) risk. In contrast, CpG island methylator phenotype (CIMP) is defined as high levels of cancer-specific methylation and provides distinct molecular and clinicopathological features of GC. The association between those two types of methylation in GC remains unclear. We examined DNA methylation of well-validated H. pylori infection associated genes in GC and its adjacent mucosa and investigated its association with CIMP, various molecular subtypes and clinical features. We studied 50 candidate loci in 24 gastric samples to identify H. pylori infection associated genes. Identified loci were further examined in 624 gastric tissue from 217 primary GC, 217 adjacent mucosa, and 190 mucosae from cancer-free subjects. We identified five genes (IGF2, SLC16A2, SOX11, P2RX7, and MYOD1) as hypermethylated in H. pylori infected gastric mucosa. In non-neoplastic mucosa, methylation of H. pylori infection associated genes was higher in patients with GC than those without. In primary GC tissues, higher methylation of H. pylori infection associated genes correlated with CIMP-positive and its related features, such as MLH1 methylated cases. On the other hand, GC with lower methylation of these genes presented aggressive clinicopathological features including undifferentiated histopathology, advanced stage at diagnosis. H. pylori infection associated DNA methylation is correlated with CIMP, specific molecular and clinicopathological features in GC, supporting its utility as promising biomarker in this tumor type.

A stag beetle knife can achieve stabler and safer endoscopic submucosal dissection in the esophagus.

Background and study aims Esophageal endoscopic submucosal dissection (ESD) has a higher complication rate than gastric ESD. Scissor-type devices, including the stag beetle (SB) knife, are reportedly safer and have shorter procedure times than tip devices. To clarify the characteristics of the SB knife, we compared the treatment outcomes of esophageal ESD with a tip-type knife to those with an SB knife combination. Patients and methods Between January 2016 and March 2023, clinical data from 197 lesions in 178 patients who underwent esophageal ESD were analyzed retrospectively. Every lesion was assigned to either the tip-type group or the SB group based on the devices with which the submucosa was initially dissected. We compared procedure time and complications and analyzed the risk of muscular exposure using multivariate analysis. Results Procedure time was not significantly different between the tip-type and SB groups (60.3±42.2 min vs. 58.8±29.1 min). The variation in procedure time was significant according to F test P =0.002). Incidence of muscular exposure was significantly lower in the SB group than in the tip-type group (24.5% vs. 11.1%, P =0.016). These differences were significant in resected specimens larger than 21 mm. Procedure time over 60 minutes (odds ratio [OR] 2.5, 95% confidence interval [CI]: 1.15-5.42, P =0.02) was a risk factor for muscular exposure, and submucosal dissection with an SB knife was a safety factor (OR 0.4, 95% CI: 0.18-0.89, P =0.02). Conclusions Performing esophageal ESD with an SB knife is a safe procedure with less variation in procedure time and less muscule exposure.

Clinical Outcomes With Lenvatinib in Patients Previously Treated With Atezolizumab/Bevacizumab for Advanced Hepatocellular Carcinoma.

BACKGROUND/AIM: The combination of atezolizumab plus bevacizumab (Atz/Bev) has become widely used as a first-line therapy for advanced hepatocellular carcinoma (HCC). However, for post-Atz/Bev therapy, evidence on the outcomes of molecular targeted agents, such as lenvatinib, is limited. The present study aimed to assess the clinical effectiveness of lenvatinib on advanced HCC in patients who had previously undergone Atz/Bev treatment. PATIENTS AND METHODS: Twenty patients with HCC, who received lenvatinib after Atz/Bev treatment, were enrolled in the study. In particular, we examined the impact of adverse events (AEs), such as anorexia and general fatigue. During the treatment, lenvatinib dosages were adjusted or temporarily discontinued in response to AEs. Treatment outcomes were retrospectively evaluated. RESULTS: The objective response rate (ORR) and disease control rate (DCR) for lenvatinib treatment were 25.0% and 95.0%, respectively, according to the Response Evaluation Criteria in Solid Tumors. The median progression-free survival (PFS) was 6.0 months, and the median overall survival (OS) was 10.5 months. Eleven patients experienced anorexia or fatigue, leading to a reduction in the dose of lenvatinib but not to a significant difference in the time to drug discontinuation. Importantly, there were no significant differences between the 11 anorexia/fatigue-suffering patients and the nine other patients with regard to PFS and OS. CONCLUSION: Lenvatinib can be efficacious and safe for treating advanced HCC patients previously treated with Atz/Bev, and AEs such as anorexia and general fatigue can be effectively managed without losing lenvatinib's therapeutic benefits.

Clinical Outcomes of Cabozantinib in Patients Previously Treated with Atezolizumab/Bevacizumab for Advanced Hepatocellular Carcinoma-Importance of Good Liver Function and Good Performance Status.

(1) Background: This study aimed to investigate clinical outcomes for cabozantinib in clinical practice in patients with advanced hepatocellular carcinoma (HCC) previously treated with atezolizumab plus bevacizumab (Atz/Bev), with a focus on whether patients met criteria of Child-Pugh Class A and Eastern Cooperative Oncology Group performance status (ECOG-PS) score 0/1 at baseline. (2) Methods: Eleven patients (57.9%) met the criteria of both Child-Pugh class A and ECOG-PS score 0/1 (CP-A+PS-0/1 group) and eight patients (42.1%) did not (Non-CP-A+PS-0/1 group); efficacy and safety were retrospectively evaluated. (3) Results: Disease control rate was significantly higher in the CP-A+PS-0/1 group (81.1%) than in the non-CP-A+PS-0/1 group (12.5%). Median progression-free survival, overall survival and duration of cabozantinib treatment were significantly longer in the CP-A+PS-0/1 group (3.9 months, 13.4 months, and 8.3 months, respectively) than in the Non-CP-A+PS-0/1 group (1.2 months, 1.7 months, and 0.8 months, respectively). Median daily dose of cabozantinib was significantly higher in the CP-A+PS-0/1 group (22.9 mg/day) than in the non-CP-A+PS-0/1 group (16.9 mg/day). (4) Conclusions: Cabozantinib in patients previously treated with Atz/Bev has potential therapeutic efficacy and safety if patients have good liver function (Child-Pugh A) and are in good general condition (ECOG-PS 0/1).

A case of chronic gastric anisakiasis coexisting with early gastric cancer.

Background: Anisakiasis is a parasitic disease caused by the consumption of raw or undercooked fish that is infected with Anisakis third-stage larvae. In countries, such as Japan, Italy, and Spain, where people have a custom of eating raw or marinated fish, anisakiasis is a common infection. Although anisakiasis has been reported in the gastrointestinal tract in several countries, reports of anisakiasis accompanied by cancer are rare. Case presentation: We present the rare case of a 40-year-old male patient with anisakiasis coexisting with mucosal gastric cancer. Submucosal gastric cancer was suspected on gastric endoscopy and endoscopic ultrasonography. After laparoscopic distal gastrectomy, granulomatous inflammation with Anisakis larvae in the submucosa was pathologically revealed beneath mucosal tubular adenocarcinoma. Histological and immunohistochemical investigation showed cancer cells as intestinal absorptive-type cells that did not produce mucin. Conclusion: Anisakis larvae could have invaded the cancer cells selectively because of the lack of mucin in the cancerous epithelium. Anisakiasis coexisting with cancer is considered reasonable rather than coincidental. In cancer with anisakiasis, preoperative diagnosis may be difficult because anisakiasis leads to morphological changes in the cancer.

Endoscopic features of lymphoid follicles in the colonic mucosa using the image enhanced endoscopy and its association with colorectal adenoma.

BACKGROUND/AIM: Lymphoid follicles hyperplasia (LH) is sometimes observed in the normal colon as small, round, yellowish-white nodules. LH is associated with food hypersensitivity and bowel symptoms and histologically characterized as intense infiltration of lymphocytes or plasmacytes. It is suggested that LH represents inflammatory immune response in the colonic mucosa. We investigated the presence of LH in the normal colonic mucosa and its association with incidence of colorectal lesions including colorectal cancer, adenoma and hyperplastic polyp. PATIENTS/METHODS: 605 participants undergoing colonoscopy for various indications were enrolled. Presence of LH in the proximal colon (appendix, cecum and the ascending colon) was observed using the blue laser imaging (BLI) endoscopy, a new generation image enhanced endoscopy (IEE) system. LH was defined as well demarcated white nodules. Elevated LH with erythema was distinguished as LH severe. Association between presence of LH and occurrence of colorectal lesions was investigated. RESULTS: Prevalence of all colorectal lesions and adenoma were significantly lower in LH severe group compared to the LH negative group (P = 0.0008, 0.0009, respectively). Mean number of all colorectal lesions and adenoma were also lower in LH severe group compared to the LH negative group (P = 0.005, 0.003 respectively). The logistic regression with adjustment for gender and age demonstrated that presence of LH severe held significantly lower risk of all colorectal lesions (OR = 0.48, 95%CI = 0.27-0.86) and adenoma (OR = 0.47, 95%CI = 0.26-0.86). CONCLUSION: LH in the colonic mucosa visualized by IEE is useful endoscopic finding to predict risk of colorectal adenoma.

Comprehensive DNA methylation profiling of Barrett's esophagus and esophageal adenocarcinoma in Japanese patients.

Molecular mechanisms of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) remain unclear in Japanese patients. Japanese EACs frequently have underlying short length BE: short-segment BE (SSBE), for which, neoplastic potential remains unclear. We performed comprehensive methylation profiling of EAC and BE in Japanese patients, mostly comprised with SSBE. Using three different groups of biopsies obtained from non-neoplastic BE from patients without cancer (n = 50; N group), with EAC (n = 27; ADJ group) and EAC (n = 22; T group), methylation statuses of nine candidate genes (N33, DPYS, SLC16A12, CDH13, IGF2, MLF1, MYOD1, PRDM5, and P2RX7) were examined by the bisulfite pyrosequencing. Reduced representation bisulfite sequencing was performed to characterize the genome-wide methylation status in 32 samples (12 from N, 12 ADJ, and 8 from T groups). In the candidate approach, methylation levels of N33, DPYS, and SLC16A12 were higher in ADJ and T groups compared to that in N group. The ADJ group was an independent factor for higher DNA methylation in non-neoplastic BE. The genome-wide approach demonstrated an increase of hypermethylation from ADJ to T groups relative to N group near the transcription start sites. Among gene groups hypermethylated in ADJ and T groups (n = 645) and T group alone (n = 1438), 1/4 and 1/3 were overlapped with downregulated genes in the microarray data set, respectively. Accelerated DNA methylation is observed in EAC and underlying BE in Japanese patients, mostly comprised with SSBE, highlighting the potential impact of methylation in early carcinogenesis.

Large Inflammatory Myofibroblastic Tumor of the Esophagus: A Case Report and Literature Review.

Inflammatory myofibroblastic tumor (IMT) is a rare tumor composed of myofibroblasts with inflammatory blood cell infiltration. It commonly occurs in the lungs and rarely in the esophagus. We herein report a valuable case of IMT originating in the esophagus. A 60-year-old Japanese woman with dysphagia had a large subepithelial lesion in the cervical esophagus, which was 15 cm in length. Surgical resection was performed to confirm the pathological diagnosis and improve the symptoms. The postoperative diagnosis was IMT composed of multiple nodules. There was no recurrence or metastasis within one year after surgery.

The Association between the Growth Pattern and Malignancy in the Formation of Ulceration in Gastric Gastrointestinal Stromal Tumor.

Objective In general, surface ulceration in gastric gastrointestinal stromal tumor (GIST) is considered a malignant feature; however, the mechanism underlying its formation has not been evaluated in detail. In this study, we analyzed the factors involved in ulceration using resected specimens of gastric GIST. Methods A total of 48 samples were retrospectively analyzed. We examined the association of surface ulceration of gastric GIST with the MIB-1 labeling index, mitotic number, tumor size, endoscopic ultrasound (EUS) findings and growth pattern on computed tomography (CT). Results The proportion of men was significantly higher in the ulceration group than in the non-ulceration group (p=0.04146), whereas age was not significantly different between the groups. Tumor was significantly larger in the ulceration group than in the non-ulceration group (p=0.0048). There was no correlation between tumor size and ulcer number. The MIB-1 index was not related to ulceration, nor were EUS findings. The number of mitotic cells tended to be higher in the ulceration group than in the non-ulceration group (p=0.05988). Intraluminal growth pattern was strongly associated with ulceration (p=0.00019). After a multivariate analysis, the growth pattern was the only factor associated with ulceration of gastric GIST. Conclusion Although formation of surface ulceration in gastric GIST was partially associated with the degree of malignancy, the growth pattern was the most important factor associated with ulceration in gastric GIST.

Current Status of the Diagnosis of Early-Stage Pancreatic Ductal Adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) can be treated with surgery, chemotherapy, and radiotherapy. Despite medical progress in each field in recent years, it is still insufficient for managing PDAC, and at present, the only curative treatment is surgery. A typical pancreatic cancer is relatively easy to diagnose with imaging. However, it is often not recommended for surgical treatment at the time of diagnosis due to metastatic spread beyond the pancreas. Even if it is operable, it often recurs during postoperative follow-up. In the case of PDAC with a diameter of 10 mm or less, the 5-year survival rate is as good as 80% or more, and the best index for curative treatment is tumor size. The early detection of pancreatic cancer with a diameter of less than 10 mm or carcinoma in situ is critical. Here, we provide an overview of the current status of diagnostic imaging features and genetic tests for the accurate diagnosis of early-stage PDAC.

A rare case of inflammatory polyp in the common bile duct with cholangitis.

The diagnosis of bile duct tumors can be difficult at times. A transpapillary bile duct biopsy findings with endoscopic retrograde cholangiopancreatography sometimes contradict diagnostic imaging findings. In bile duct tumors, inflammatory polyps in the extrahepatic bile duct are relatively rare with extrahepatic cholangitis. The disease's clinical relevance, including its natural history and prognosis, is not always clear. We show here a rare case of an inflammatory polyp in the common bile duct. A 69-year-old woman with abdominal pain was diagnosed with cholangitis. The findings of contrast-enhanced computed tomography and magnetic resonance cholangiopancreatography suggested that she had extrahepatic cholangiocarcinoma. The examination and therapy of cholangitis were performed by endoscopic retrograde cholangiopancreatography. The cholangiography revealed a suspected tumor in the hilar bile duct with some common bile duct stones. Then, after endoscopic sphincterotomy to remove tiny common bile duct stones, further detailed examinations were performed at the same time using an oral cholangioscope revealed a papillary raised lesion with a somewhat white surface in the bile duct; a biopsy was conducted on the same spot, and epithelial cells with mild atypia appeared in the shape of a papilla. Since the malignant tumor or the intraductal papillary neoplasm of the bile duct could not be ruled out, extrahepatic bile duct resection was conducted with the patient's informed consent. Bile duct inflammatory polyp was the histopathological diagnosis.

Scoring system for predicting the prognosis of elderly gastric cancer patients after endoscopic submucosal dissection.

OBJECTIVES: Comprehensive assessments of the long-term outcomes of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) in the elderly are unavailable. We aimed to create a scoring system to predict the long-term prognosis after ESD for EGC among patients aged ≥75 years. METHODS: We conducted retrospective studies of two cohorts: a single-center cohort (2006-2011) for developing the scoring system, and a multicenter cohort for validating the developed system (2012-2016). In the development cohort, factors related to death after ESD were identified using multivariable Cox regression analysis, and a predictive scoring system was developed. In the validation cohort, the scoring system was validated in 295 patients. RESULTS: In the development cohort, Charlson comorbidity index (CCI) ≥3 (hazard ratio [HR] 3.017), high psoas muscle index (PMI) (HR 2.206), and age ≥80 years (HR 1.978) were significantly related to overall survival after ESD. Therefore, high CCI, low PMI, and age ≥80 years were assigned 1 point each. The patients were categorized into low (≤1 point) and high (≥2 points) score groups based on their total scores. In the validation cohort, 184 and 111 patients were assigned to the low- and high-score groups, respectively. In comparisons based on Kaplan-Meier curves, the 5-year survival rate was 91.5% in the low-score group and 57.8% in the high-score group (log-rank test; P < 0.001). CONCLUSION: Our scoring system including high CCI, low PMI, and age ≥80 years could stratify the long-term prognosis of elderly patients aged ≥75 years after ESD for EGC.

Diagnosis of ulcerative colitis and Crohn's disease using transabdominal ultrasonography.

The following are some common features of ulcerative colitis (UC) and Crohn's disease (CD) on transabdominal ultrasonography (TUS). UC, which consists primarily of mucosal inflammation, is seen on TUS as wall thickening with preserved layer structure continuing from the rectum in the active phase of UC. Inflammation confined to the mucosa is seen as thickening of the mucosal/submucosal layers. When the inflammation becomes severe, the echogenicity of the submucosal layer decreases and the layer structure becomes indistinct. CD, which consists primarily of discontinuous transmural inflammation, shows more pronounced hypoechoic wall thickening than UC at the transmural inflammation. On TUS, the layer structure becomes indistinct and gradually disappears due to the depth of the myriad inflammation during the active phase of CD. It is important to evaluate the changes in wall thickening and layer structure when diagnosing UC and CD with TUS. In addition, diagnostic techniques such as color Doppler and contrast-enhanced ultrasonography, which can be used to assess blood flow, and elastography, which can be used to evaluate stiffness, are also used. Thus, TUS is a noninvasive and convenient modality that shows promise as a useful examination for diagnosis of UC and CD.

Changes in intestinal bacteria and imbalances of metabolites induced in the intestines of pancreatic ductal adenocarcinoma patients in a Japanese population: a preliminary result.

BACKGROUND: The relationship between pancreatic ductal adenocarcinoma (PDAC) and the intestinal environment is not fully understood. The purpose of this study was to elucidate the characteristics of the intestinal environment in PDAC. METHODS: We performed a case-control study of 5 Japanese patients with unresectable PDAC located in the body or tail (PDAC-bt). The number of patients analyzed was limited for this preliminary study. We included 68 healthy subjects, herein control, of pre-printed study in the preliminary study. 16S rRNA amplicon sequencing and metabolomic analysis were performed using fecal samples from the subjects. RESULTS: There was no difference in the Shannon index and Principal Coordinate Analysis between PDAC-bt and the control. However, a significant increase in oral-associated bacteria (Actinomyces, Streptococcus, Veillonella, Lactobacillus) was observed. A significant decrease of Anaerostipes was demonstrated in the feces of PDAC-bt compared with the control. The intestinal propionic acid and deoxycholic acid were significantly lower in PDAC-bt compared with the control. CONCLUSIONS: We showed that the intestinal environment of PDAC-bt is characterized by an increase in oral-associated bacteria and an imbalance of metabolites but without changes in alpha and beta diversity of the gut microbiota profiles.Clinical Trial Registration: www.umin.ac.jp, UMIN 000041974, 000023675, 000023970.

Endoscopic imaging in inflammatory bowel disease.

In inflammatory bowel disease, including Crohn's disease and ulcerative colitis, an excessive immune response due primarily to T-cell lymphocytes causes inflammation in the gastrointestinal tract. Lesions in Crohn's disease can occur anywhere in the gastrointestinal tract, i.e., from the oral cavity to the anus. Endoscopically, aphthoid lesions/ulcers believed to be initial lesions progress to discrete ulcers, which coalesce to form a longitudinal array and progress to longitudinal ulcers with a cobblestone appearance, which is a typical endoscopic finding. Before long, complications such as strictures, fistulas, and abscesses form. Lesions in ulcerative colitis generally extend continuously from the rectum and diffusely from a portion of the colon to the entire colon. Endoscopically, lack of vascular pattern, fine granular mucosa, erythema, aphthae, and small yellowish spots are seen in mild cases; coarse mucosa, erosions, small ulcers, bleeding (contact bleeding), and adhesion of mucous, bloody, and purulent discharge in moderate cases; and widespread ulcers and marked spontaneous bleeding in severe cases.

Injury to the muscle layer, increasing the risk of post-colorectal endoscopic submucosal dissection electrocoagulation syndrome.

BACKGROUND AND AIM: In colorectal endoscopic submucosal dissection (ESD), post-ESD electrocoagulation syndrome (PECS) has been recognized as one of the major complications. There are no reports on the relationships between ESD findings and PECS. This study aims to evaluate the risk factors for PECS, including ESD findings such as muscularis propria exposure. METHODS: We performed a retrospective cohort study of patients who underwent colorectal ESD between January 2017 and December 2021 in Japan. The grade of injury to the muscle layer caused by ESD was categorized as follows: Grade 0, no exposure of muscularis propria; Grade 1, muscularis propria exposure; Grade 2, torn muscularis propria; and Grade 3, colon perforation. The risk factors for PECS, including injury to the muscle layer, were analyzed by univariate and multivariate analyses. RESULTS: Out of 314 patients who underwent colorectal ESD, PECS occurred in 28 patients (8.9%). The multivariate analysis showed that female sex (odds ratio [OR] 3.233; 95% confidence interval [95% CI]: 1.264-8.265, P = 0.014), large specimen size (≥ 40 mm) (OR 6.138; 95% CI: 1.317-28.596, P = 0.021), long procedure time (≥ 90 min) (OR 2.664; 95% CI: 1.053-6.742, P = 0.039), and Grade 1 or 2 injury to the muscle layer (OR 3.850; 95% CI: 1.090-13.61, P = 0.036) were independent risk factors for PECS. CONCLUSIONS: Injury to the muscle layer, such as exposure or tear, was identified as a novel independent risk factor for PECS. We should perform colorectal ESD carefully to avoid injuring the muscle layers.

Detection and Characterization of Gastric Cancer Using Cascade Deep Learning Model in Endoscopic Images.

Endoscopy is widely applied in the examination of gastric cancer. However, extensive knowledge and experience are required, owing to the need to examine the lesion while manipulating the endoscope. Various diagnostic support techniques have been reported for this examination. In our previous study, segmentation of invasive areas of gastric cancer was performed directly from endoscopic images and the detection sensitivity per case was 0.98. This method has challenges of false positives and computational costs because segmentation was applied to all healthy images that were captured during the examination. In this study, we propose a cascaded deep learning model to perform categorization of endoscopic images and identification of the invasive region to solve the above challenges. Endoscopic images are first classified as normal, showing early gastric cancer and showing advanced gastric cancer using a convolutional neural network. Segmentation on the extent of gastric cancer invasion is performed for the images classified as showing cancer using two separate U-Net models. In an experiment, 1208 endoscopic images collected from healthy subjects, 533 images collected from patients with early stage gastric cancer, and 637 images from patients with advanced gastric cancer were used for evaluation. The sensitivity and specificity of the proposed approach in the detection of gastric cancer via image classification were 97.0% and 99.4%, respectively. Furthermore, both detection sensitivity and specificity reached 100% in a case-based evaluation. The extent of invasion was also identified at an acceptable level, suggesting that the proposed method may be considered useful for the classification of endoscopic images and identification of the extent of cancer invasion.

Novel image enhancement technology that helps find bleeding points during endoscopic submucosal dissection of gastric neoplasms.

BACKGROUND AND AIM: The management of bleeding during endoscopic submucosal dissection (ESD) is critical and related to the procedure time. We collaborated on a new image enhancement algorithm with parameter optimization for clinical use being developed by FUJIFILM Co. and processed white light image data offline to evaluate the effectiveness of this technology. This study aims to evaluate the clinical usefulness of this technology. METHODS: Eighteen video scenes of bleeding points from five gastric ESDs were selected and processed by the new image enhancement algorithm. The time until a bleeding point was found, visibility of a bleeding point, and color abnormality of the submucosal layer were evaluated by ESD experts, ESD trainees, and endoscopy trainees. The color differences between the bleeding point and the surroundings in CIE-L*a*b* color space were calculated in the original and enhanced images. RESULTS: The time until a bleeding point was found in the enhanced videos was significantly shorter than that in the original videos (11.10 s vs 13.85 s) (P = 0.017). On a 5-point (-2 to +2) Likert scale of visibility, the enhanced image was slightly superior to the original (+0.45), and the appearance of the submucosa was comparable between images (+0.14). The color difference among the bleeding areas on the enhanced images was significantly larger than that on the original images (10.93 vs 8.36). CONCLUSION: This novel image enhancement algorithm emphasizes the color difference between a bleeding point and the surrounding area, which would help find bleeding points faster during ESD for the less experienced endoscopists.

Complete omission of second-look endoscopy after gastric endoscopic submucosal dissection in real-world practice.

Gastric endoscopic submucosal dissection (ESD) is increasingly performed in patients receiving antithrombotic therapy. Second-look endoscopy (SLE) has been performed empirically in several clinical settings. We investigated whether SLE omission was associated with an increased risk of postESD bleeding in all patients, including those administered antithrombotic agents. Between July 2016 and June 2018, 229 patients were treated with a clinical pathway for gastric ESD that involved SLE on the day after ESD (SLE group). Between September 2018 and May 2020, 215 patients were treated using a clinical pathway that did not include SLE (nonSLE group). We retrospectively compared the incidence of postESD bleeding among the propensity score-matched cohorts and determined the risk factors for postESD bleeding using multivariate analysis. The propensity score-matched cohorts showed no significant differences in the incidence of postESD bleeding between the SLE (3.2%) and nonSLE (5.1%) groups. Multivariate analysis revealed that the presence of lesions in the lower gastric body (adjusted odds ratio [OR] 2.17, 95% confidence interval [CI] 1.06-4.35, P.03) was a significant risk factor for postESD bleeding during admission, whereas resected specimen size ≥ 40 mm (adjusted OR 3.21, 95% CI 1.19-8.19, P.02) and antiplatelet therapy (adjusted OR 4.16, 95% CI 1.47-11.80, P.007) were significant risk factors after discharge. Complete omission of SLE after gastric ESD does not increase postESD bleeding in clinical practice.