A Modified eCura System to Stratify the Risk of Lymph Node Metastasis in Undifferentiated-Type Early Gastric Cancer After Endoscopic Resection.

Purpose: The original eCura system was designed to stratify the risk of lymph node metastasis (LNM) after endoscopic resection (ER) in patients with early gastric cancer (EGC). We assessed the effectiveness of a modified eCura system for reflecting the characteristics of undifferentiated-type (UD)-EGC.

Materials And Methods: Six hundred thirty-four patients who underwent non-curative ER for UD-EGC and received either additional surgery (radical surgery group; n=270) or no further treatment (no additional treatment group; n=364) from 18 institutions between 2005 and 2015 were retrospectively included in this study.

Combined DNA Methylation and Gastric Microbiome Marker Predicts -Negative Gastric Cancer.

Background/aims: While DNA methylation and gastric microbiome are each associated with gastric cancer (GC), their combined role in predicting GC remains unclear. This study investigated the potential of a combined DNA methylation and gastric microbiome signature to predict -negative GC.

Methods: In this case-control study, we conducted quantitative methylation-specific polymerase chain reaction to measure the methylation levels of , , , , , and in the gastric mucosa from 75 -negative patients, including chronic gastritis (CG), intestinal metaplasia (IM), and GC.

Developing Operational Definitions Related to Eradication Therapy.

Background: The lack of well-established operational definitions is a major limitation of eradication studies that use secondary databases. We aimed to develop and validate operational definitions related to eradication therapy.

Methods: Operational definitions were developed by analyzing a nationwide eradication registry and validated using real-world data from hospital medical records.

Sample Collection Methods in Upper Gastrointestinal Research.

In recent years, significant translational research advances have been made in the upper gastrointestinal (GI) research field. Endoscopic evaluation is a reasonable option for acquiring upper GI tissue for research purposes because it has minimal risk and can be applied to unresectable gastric cancer. The optimal number of biopsy samples and sample storage is crucial and might influence results.

[Gastric Cancer and Gastric Microbiome].

Gastric cancer remains a significant disease burden in Korea, with infections being the most crucial risk factor. With the advent of next-generation sequencing, the role of gastric microbiota in gastric cancer has attracted increasing attention. Studies have shown that the gastric microbiota of patients with gastric cancer differs in composition from that of the controls, with reduced microbial diversity.

External Validation of the eCura System for Undifferentiated-Type Early Gastric Cancer with Noncurative Endoscopic Resection.

Background/aims: The eCura system, a scoring model for stratifying the lymph node metastasis risk after noncurative endoscopic resection for early gastric cancer (EGC), has been internally validated, primarily for differentiated-type EGC. We aimed to externally validate this model for undifferentiated-type EGC.

Methods: This multicenter, retrospective cohort study included 634 patients who underwent additional surgery (radical surgery group, n=270) or were followed up without additional treatment (no additional treatment group, n=364) after noncurative endoscopic resection for undifferentiated-type EGC between 2005 and 2015.

Altered Gastric Microbiota and Inflammatory Cytokine Responses in Patients with -Negative Gastric Cancer.

The role of the gastric mucosal microbiome in -negative gastric cancer (GC) remains unclear. Therefore, we aimed to characterize the microbial alterations and host inflammatory cytokine responses in -negative GC. Gastric mucosal samples were obtained from 137 -negative patients with GC ( = 45) and controls (chronic gastritis or intestinal metaplasia, = 92).

Risk of post-polypectomy bleeding after endoscopic mucosal resection in patients receiving antiplatelet medication: comparison between the continue and hold groups.

Background: Current guidelines recommend continuing aspirin and discontinuing clopidogrel for colon polypectomy, but evidence for endoscopic mucosal resection (EMR) is insufficient. We aimed to assess post-polypectomy bleeding (PPB) in patients receiving antiplatelet agents and underwent EMR for various polyp sizes.

Methods: A single-center, prospective observational study was performed.

Comparison of long-term outcomes of endoscopic submucosal dissection and surgery for undifferentiated-type early gastric cancer meeting the expanded criteria: a systematic review and meta-analysis.

Background: There have been concerns over the long-term outcomes of endoscopic submucosal dissection (ESD) for undifferentiated-type early gastric cancer (UD EGC). We aimed to compare the long-term outcomes of ESD and surgery for patients with UD EGC.

Methods: We searched PubMed, Embase, and Cochrane Library databases through March 2021 to identify studies that compared the long-term outcomes of ESD and surgery for UD EGC meeting expanded criteria for curative resection.

Long-Term Clinical Outcomes of Gastric MALT Lymphoma: A Nationwide Multicenter Study in Korea.

Background: Treatment recommendations for gastric mucosa-associated lymphoid tissue (MALT) lymphoma are based on case series and expert opinions. Only a few previous studies have focused on the long-term outcomes of gastric MALT lymphoma, especially according to stage.

Methods: Patients diagnosed with gastric MALT lymphoma from January 2000 to December 2018 at nine university hospitals in Korea were included.

Evidence based guidelines for the treatment of Helicobacter pylori infection in Korea 2020.

Helicobacter pylori infection is one of the most common infectious diseases worldwide. H. pylori is responsible for substantial gastrointestinal morbidity with a high disease burden.

Endoscopic Treatment for Superficial Nonampullary Duodenal Tumors.

Superficial nonampullary duodenal epithelial tumors are considered rare but have been increasingly recognized in recent years. Accordingly, the importance of endoscopic treatment for the lesions are also increasing. An endoscopic resection can be considered for duodenal adenoma and mucosal cancer.

Long-term outcomes of endoscopic resection followed by additional surgery after non-curative resection in undifferentiated-type early gastric cancer: a nationwide multi-center study.

Background: Undifferentiated-type early gastric cancer (UD EGC) shows lower curative resection rates after endoscopic submucosal dissection (ESD). Additional surgery is recommended after non-curative resection. We evaluated the long-term outcomes of ESD followed by additional surgery after non-curative resection in UD EGC compared to those for surgery as initial treatment.

Long-term Outcomes of Undifferentiated-Type Early Gastric Cancer with Positive Horizontal Margins after Endoscopic Resection.

Background/aims: This study examined the long-term outcomes of undifferentiated-type early gastric cancer (UD EGC) with positive horizontal margins (HMs) after endoscopic resection (ER) and compared them between additional surgery and nonsurgical management.

Methods: From 2005 to 2015, a total of 1,124 patients with UD EGC underwent ER at 18 tertiary hospitals in Korea. Of them, 92 patients with positive HMs as the only noncurative factor (n=25) or with both positive HMs and tumor size >2 cm (n=67) were included.

Prediction model for curative endoscopic submucosal dissection of undifferentiated-type early gastric cancer.

Background: Endoscopic submucosal dissection (ESD) is an effective treatment for early gastric cancer (EGC); however, its curative resection rate is low for undifferentiated-type EGC. We developed and externally validated a prediction model for curative ESD of undifferentiated-type EGC.

Methods: In this cross-sectional study, we included 448 patients who underwent ESD for undifferentiated-type EGC at 18 hospitals in Korea between 2005 and 2015 in the development cohort and 1342 patients who underwent surgery at two hospitals in the validation cohort.

Evidence-Based Guidelines for the Treatment of Infection in Korea 2020.

infection is one of the most common infectious diseases worldwide. Although the prevalence of is gradually decreasing, approximately half of the world's population still becomes infected with this disease. is responsible for substantial gastrointestinal morbidity worldwide, with a high disease burden.

Deep Neural Network-Based Prediction of the Risk of Advanced Colorectal Neoplasia.

Background/aims: Risk prediction models using a deep neural network (DNN) have not been reported to predict the risk of advanced colorectal neoplasia (ACRN). The aim of this study was to compare DNN models with simple clinical score models to predict the risk of ACRN in colorectal cancer screening.

Methods: Databases of screening colonoscopy from Kangbuk Samsung Hospital (n=121,794) and Kyung Hee University Hospital at Gangdong (n=3,728) were used to develop DNN-based prediction models.

[Management of Peptic Ulcer Bleeding in Patients Taking Aspirin or Anticoagulant].

Antiplatelet and anticoagulation agents are increasingly prescribed for secondary prophylaxis in patients with cardiovascular and cerebrovascular diseases. These drugs are associated with an increased risk of gastrointestinal bleeding, including peptic ulcer bleeding. It is difficult to decide when to restart the agents after peptic ulcer bleeding in these patients because the risk of rebleeding and thromboembolism should be balanced.

Comparison between endoscopic submucosal resection and surgery for the curative resection of undifferentiated-type early gastric cancer within expanded indications: a nationwide multi-center study.

Background And Aims: Endoscopic submucosal dissection (ESD) for undifferentiated early gastric cancer (UD EGC) has debate due to the risk of lymph node metastasis. We investigated the outcomes of ESD compared to those of surgery for the UD EGC within expanded indication.

Methods: We reviewed 971 UD EGC patients performed ESD across 18 hospitals in Korea and 1812 patients who underwent surgical resection in two hospitals between February 2005 and May 2015.

Clinical Guidelines for Drug-Related Peptic Ulcer, 2020 Revised Edition.

Korean guidelines for nonsteroidal anti-inflammatory drug (NSAID)-induced peptic ulcer were previously developed in 2009 with the collaboration of the Korean College of and Upper Gastrointestinal Research and Korean Society of Gastroenterology. However, the previous guidelines were based mainly upon a review of the relevant literature and expert opinion. Therefore, the guidelines need to be revised.

Application of deep learning to predict advanced neoplasia using big clinical data in colorectal cancer screening of asymptomatic adults.

Background/aims: We aimed to develop a deep learning model for the prediction of the risk of advanced colorectal neoplasia (ACRN) in asymptomatic adults, based on which colorectal cancer screening could be customized.

Methods: We collected data on 26 clinical and laboratory parameters, including age, sex, smoking status, body mass index, complete blood count, blood chemistry, and tumor marker, from 70,336 first-time colonoscopy screening recipients. For reference, we used a logistic regression (LR) model with nine variables manually selected from the 26 variables.

Usefulness of narrow-band imaging for the detection of remnant sessile-serrated adenoma (SSA) tissue after endoscopic resection: the KASID multicenter study.

Background: A sessile-serrated adenoma (SSA) has a high risk for incomplete resection. Little is known regarding how to immediately detect remnant SSA tissue after endoscopic resection. We investigated the usefulness of narrow-band imaging (NBI) to detect remnant SSA tissue after endoscopic mucosal resection (EMR).

[Clinical Guidelines for Drug-induced Peptic Ulcer, 2020 Revised Edition].

The Korean guidelines for nonsteroidal anti-inflammatory drug (NSAID)-induced peptic ulcers were previously developed under co-work with the Korean College of and Upper Gastrointestinal Research and Korean Society of Gastroenterology at 2009. On the other hand, the previous guidelines were based mainly on a literature review and expert opinions. Therefore, the guidelines need to be revised.

Low Levels of Alcohol Consumption and Risk of Intestinal Metaplasia: A Cohort Study.

Background: The impact of alcohol drinking on gastric precancerous lesions remains unclear. We investigated the relationship of alcohol intake with risk of atrophic gastritis (AG) and intestinal metaplasia (IM).

Methods: This study included 202,675 Korean adults free from AG and IM on their initial endoscopy who were followed with repeated endoscopic examinations.