The role of PD-1/PD-L1 pathway in ulcerative colitis and changes following tonsil-derived mesenchymal stem cells treatment.

Background/aims: The programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway has not been fully evaluated in inflammatory bowel disease. We evaluated PD-1/PD-L1 levels in patients with ulcerative colitis (UC) and their significance in tonsil-derived mesenchymal stem cells (TMSCs) treatment.

Methods: Using acute and chronic murine colitis model, we measured the PD-1 and PD-L1 levels in inflamed colonic tissues pre- and post-treatment with TMSCs.

Different modifiable risk factors for the development of non-advanced adenoma, advanced adenomatous lesion, and sessile serrated lesions, on screening colonoscopy.

The development of premalignant colorectal polyps is significantly influenced by various lifestyle and modifiable risk factors. In our study, we used a large cohort of 9025 patients, who underwent screening colonoscopies at a university hospital, to assess the risk factors associated with the development of three different colorectal cancer precursor lesions: non-advanced adenomas (NAs), advanced adenomatous lesions (ADLs), and sessile serrated lesions (SSLs). Among the participants, 3641 had NAs, 836 had ADLs, and 533 had SSLs.

Integrated Analysis of Microbiome and Metabolome Reveals Disease-Specific Profiles in Inflammatory Bowel Diseases and Intestinal Behçet's Disease.

The gut microbial and metabolic characteristics of intestinal Behçet's disease (BD), a condition sharing many clinical similarities with ulcerative colitis (UC) and Crohn's disease (CD), are largely unexplored. This study investigated the gut microbial and metabolic characteristics of intestinal BD as well as potential biomarkers, comparing them with those in UC, CD, and healthy controls. Colon tissue and stool samples from 100 patients (35 UC, 30 CD, and 35 intestinal BD) and 41 healthy volunteers were analyzed using 16S ribosomal RNA sequencing to assess microbial diversity, taxonomic composition, and functional profiling.

Primary surgery versus pharmacotherapy for newly diagnosed ileocecal Crohn's disease: a hospital-based cohort study.

Background/aims: Limited knowledge exists regarding the optimal timing and relative advantages of primary surgery compared to medical treatment in ileocecal Crohn's disease (CD). This study aimed to compare long-term outcomes between medication-based treatment versus surgery in newly diagnosed ileocecal CD patients in an Asian population.

Methods: Among the 885 patients diagnosed with CD and enrolled in the study site hospital cohort between 1980 and 2013, 93 (10.

Medical disputes related to advanced endoscopic procedures with endoscopic retrograde cholangiopancreatography or endoscopic ultrasonography for the management of pancreas and biliary tract diseases.

Background/aims: This study aimed to evaluate the characteristics of endoscopic retrograde cholangiopancreatography (ERCP) or endoscopic ultrasonography (EUS)-related adverse events (AEs) that eventually lead to medical disputes or claims on medical professional liability.

Methods: Medical disputes for ERCP/EUS-related AEs filed in the Korea Medical Dispute Mediation and Arbitration Agency between April 2012 and August 2020 were evaluated using corresponding medical records. AEs were categorized into three sections: procedure-related, sedation-related, and safety-related AEs.

Cancer risk in patients with Peutz-Jeghers syndrome in Korea: a retrospective multi-center study.

Background/aims: There have been little research on the cancer risks of patients with Peutz-Jeghers syndrome (PJS) in Korea. We aimed to investigate the clinical features of PJS patients and their cancer incidence rate.

Methods: Patients with PJS from nine medical centers were enrolled.

New sedatives and analgesic drugs for gastrointestinal endoscopic procedures.

Procedural sedation has become increasingly common in endoscopy. Sedatives and analgesics induce anxiolysis and amnesia. In addition, an appropriate level of sedation is necessary for safe procedures including therapeutic endoscopy.

2021 Korean Society of Gastrointestinal Endoscopy Clinical Practice Guidelines for Endoscopic Sedation.

Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing.

[2021 Korean Society of Gastrointestinal Endoscopy Clinical Practice Guidelines for Endoscopic Sedation].

Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing.

Physician education can minimize inappropriate steroid use in patients with inflammatory bowel disease: the ACTION study.

Background/aims: Epidemiological data on steroid use in South Korean patients with inflammatory bowel disease (IBD) are limited. We documented the steroid use patterns in these patients, and whether physician education on appropriate steroid use affected these patterns.

Methods: ACTION was an observational cohort study conducted in adults (≥19 years) with IBD.

2021 Korean Society of Gastrointestinal Endoscopy Clinical Practice Guidelines for Endoscopic Sedation.

Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing.

C-reactive protein is associated with postoperative outcomes in patients with intestinal Behçet's disease.

Background: Patients with intestinal Behçet's disease (BD) frequently undergo intestinal resections, which significantly affects postoperative morbidity and mortality. The aim of this study was to identify the association between C-reactive protein (CRP) levels and postoperative outcomes in patients with intestinal BD who underwent surgical bowel resection.

Methods: Patients who were diagnosed with intestinal BD and underwent intestinal surgery due to BD at Severance Hospital between November 2005 and April 2018 were retrospectively investigated.

Three-dimensional culture method enhances the therapeutic efficacies of tonsil-derived mesenchymal stem cells in murine chronic colitis model.

Tonsil-derived mesenchymal stem cells (TMSCs) showed therapeutic effects on acute and chronic murine colitis models, owing to their immunomodulatory properties; therefore, we evaluated enhanced therapeutic effects of TMSCs on a murine colitis model using three-dimensional (3D) culture method. The expression of angiogenic factors, VEGF, and anti-inflammatory cytokines, IL-10, TSG-6, TGF-β, and IDO-1, was significantly higher in the 3D-TMSC-treated group than in the 2D-TMSC-treated group (P < 0.05).

Cost-Effectiveness, Efficacy, and Safety Analysis of Tailored Therapy in Patients with Infection.

Recently in Korea, where triple therapy is accepted as the first-line () eradication treatment, antibiotic resistance to clarithromycin has increased considerably, resulting in eradication rates of less than 80%. We investigated the efficacy of tailored therapy after a clarithromycin resistance test compared with empirical therapy for eradication. The cost-effectiveness of eradication success was evaluated according to the average medical cost per patient.

Comparison of Long-Term Outcomes of Infliximab versus Adalimumab Treatment in Biologic-Naïve Patients with Ulcerative Colitis.

Background/aims: The tumor necrosis factor-α inhibitors infliximab and adalimumab are standard treatments for moderate to severe ulcerative colitis (UC). However, there has been no headto- head comparison of treatment efficacy and outcomes between the two agents. The aim of this study was to compare the efficacy and long-term outcomes of infliximab versus adalimumab treatment in biologic-naïve patients with UC.

mTOR Signaling Combined with Cancer Stem Cell Markers as a Survival Predictor in Stage II Colorectal Cancer.

Purpose: Wnt and mammalian target of rapamycin (mTOR) are major molecular signaling pathways associated with the development and progression of tumor, as well as the maintenance and proliferation of cancer stem cells (CSCs), in colorectal cancer (CRC). Identifying patients at risk of poor prognosis is important to determining whether to add adjuvant treatment in stage II CRC and thus improve survival. In the present study, we evaluated the prognostic value of Wnt, mTOR, and CSC markers as survival predictors in stage II CRC.

Update on the Treatment of Behcet's Disease of the Small Bowel with Biologic Agents.

Purpose Of Review: The treatment of intestinal Behcet's disease (BD) is challenging, and one-third of patients require surgery due to failure of conventional therapies. Anti-tumor necrosis factor-α (TNF-α) and other new biologics have been actively investigated for managing intestinal BD. In this article, we review the updated experiences and up-to-date clinical data on anti-TNF-α and other biologics for the management of intestinal BD.

Genotype-based Treatment With Thiopurine Reduces Incidence of Myelosuppression in Patients With Inflammatory Bowel Diseases.

Background & Aims: Thiopurine-related myelosuppression (most frequently leukopenia) interferes with thiopurine therapy for patients with inflammatory bowel diseases (IBD). We investigated whether pretreatment analyses genetic variants associated with thiopurine-induced leukopenia could be used to effectively identify patients who required dose adjustments.

Methods: We performed a multicenter, prospective study of patients with IBD at 5 tertiary medical centers in Korea, from January 2016 through September 2018.

Is fasting beneficial for hospitalized patients with inflammatory bowel diseases?

Background/aims: Patients with inflammatory bowel disease (IBD) are usually hospitalized because of aggravated gastrointestinal symptoms. Many clinicians empirically advise these patients to fast once they are admitted. However, there has been no evidence that maintaining a complete bowel rest improves the disease course.

Screening for Lung Cancer Using Low-dose Chest Computed Tomography in Korean Long-term Colorectal Cancer Survivors.

Background: The National Lung Screening Trial (NLST) and NELSON trial showed that low-dose chest computed tomography (LDCT) screening significantly reduced the mortality form lung cancer. Although cancer survivors are known to have high risk for second malignant neoplasm (SMN), the usefulness of LDCT screening for lung cancer in cancer survivors is not clear.

Methods: Between August 2016 and August 2017, 633 long-term colorectal cancer (CRC) survivors visited the survivorship clinic in Cancer Prevention Center, Yonsei Cancer Center, Seoul, Republic of Korea.

Association of Family History With Cancer Recurrence, Survival, and the Incidence of Colorectal Adenoma in Patients With Colorectal Cancer.

Background: The influence of family history (FH) on cancer recurrence and survival among patients with established colorectal cancer (CRC) remains uncertain. This study aimed to evaluate the association of FH with cancer recurrence, survival, and the incidence of colorectal adenomas in patients with CRC.

Methods: Consecutive patients with stage III CRC diagnosed between 2004 and 2009 and followed-up in Severance Hospital were retrospectively enrolled and followed until December 2014.

Feasibility of dynamic risk assessment for patients with repeated trans-arterial chemoembolization for hepatocellular carcinoma.

Background: Hepatoma arterial-embolization prognostic (HAP) score and its modifications (modified HAP [mHAP] and mHAP-II), consisting of some or all of the following factors of tumor size, number, alpha-fetoprotein, bilirubin, and serum albumin, have been found to predict outcomes after trans-arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). We investigated the feasibility of using HAP-related risk scores for dynamic risk assessment during repeated TACE.

Methods: A total of 619 HCC patients treated with TACE from two institutions between 2003 and 2010 were included.