[Old and New Biologics and Small Molecules in Inflammatory Bowel Disease: Anti Integrins].

Recently, novel biologics or small molecular drugs have been introduced for overcoming the unmet needs associated with anti-tumor necrosis factor α agents for inflammtory bowel disease (IBD) treatment. Among these novel drugs, anti integrin agents block leukocyte trafficking to the intestine by blocking the interaction between integrin and cell adhesion molecules. Vedolizumab (anti-α4ß7) is most widely used anti-integrin approved in both ulcerative colitis and Crohn's disease .It has been shown to be effective in both induction and maintenance therapy with a favorable safety profile due to gut selectivity. Several models incorporating clinical, genetic, immune and gut microbial markers to predict response to vedolizumab in IBD have been developed. Etrolizumab (anti-ß7) blocks leukocyte trafficking via α4ß7 and cell adhesion via αEß7 integrins. In addition, the introduction of subcutaneous vedolizumab showed similar efficacy and safety with improved patients' convenience. Other investigational anti-integrin therapies include abrilumab (anti-α4ß7 IgG2), PN-943 (orally administered and gut-restricted α4ß7 antagonist peptide), AJM300 (orally active small molecule inhibitor of α4), and ontamalimab (anti-MAdCAM-1 IgG).

Recent updates on classification and unsolved issues of diverticular disease: a narrative review.

Recently, a paradigm shift has occurred in the classification of diverticular disease and the understanding of its pathogenesis. Diverticular disease is now defined as a variety of clinically significant conditions such as diverticulitis, diverticular bleeding, symptomatic uncomplicated diverticular disease, and segmental colitis associated with diverticulosis. Low-grade inflammation, visceral hypersensitivity, abnormal intestinal motility, and genetic factors have emerged as the key contributors to the pathogenesis of diverticular disease. Routine antibiotic use is no longer recommended for all cases of diverticulitis, and simple recurrence is not an indication for surgical treatment. Early colonoscopy with proper preparation is recommended for the treatment of diverticular bleeding, although recent studies have not shown significant efficacy in preventing recurrence. The roles of dietary fiber, nonabsorbable antibiotics, 5-aminosalicylates, and probiotics in the prevention of diverticular disease are controversial and require further investigation.

Clinical characteristics and long-term disease course in patients with Crohn's disease as diagnosed by video capsule endoscopy: a multicenter retrospective matched case-control study.

Background/Aims: Video capsule endoscopy is rarely used to diagnose Crohn's disease in patients with negative ileocolonoscopy or cross-sectional image findings. We evaluated clinical characteristics and long-term outcomes of these rare cases. Methods: This multicenter study included patients with Crohn's disease from 3 tertiary hospitals from January 2007 to October 2022. Patients with normal findings on ileocolonoscopy and computed tomography (CT)/magnetic resonance (MR) enterography but had ulcerations at the small bowel detected by video capsule endoscopy were included. The controls were patients with abnormal findings on endoscopy or CT/MR enterography. Controls were case-matched in a ratio of 3:1 for sex, calendar year of diagnosis, and age at diagnosis. Results: Among 3,752 patients, 24 (0.6%) were diagnosed with Crohn's disease using video capsule endoscopy findings. The disease location (P< 0.001) and behavior at diagnosis (P= 0.013) of the cases significantly differed from that of controls. The perianal fistula modifier (25.0% vs. 33.3%, P= 0.446) did not differ significantly between the 2 groups. Initial disease activity and C-reactive protein and fecal calprotectin levels were significantly lower in cases versus controls. The median Lewis score was 838 (interquartile range, 393-1,803). Over 10 years of follow-up, the cases showed significantly lower cumulative risk of complicated behavior, biologics use, Crohn's disease-related hospitalization, and surgeries (log-rank test P< 0.05). Conclusions: Patients with Crohn's disease whose lesions were observed only by video capsule endoscopy were rare, and exhibit different clinical characteristics and a more favorable long-term disease course compared to those who were conventionally diagnosed.

Deep Learning Model Using Stool Pictures for Predicting Endoscopic Mucosal Inflammation in Patients With Ulcerative Colitis.

INTRODUCTION: Stool characteristics may change depending on the endoscopic activity of ulcerative colitis (UC). We developed a deep learning model using stool photographs of patients with UC (DLSUC) to predict endoscopic mucosal inflammation. METHODS: This was a prospective multicenter study conducted in 6 tertiary referral hospitals. Patients scheduled to undergo endoscopy for mucosal inflammation monitoring were asked to take photographs of their stool using smartphones within 1 week before the day of endoscopy. DLSUC was developed using 2,161 stool pictures from 306 patients and tested on 1,047 stool images from 126 patients. The UC endoscopic index of severity was used to define endoscopic activity. The performance of DLSUC in endoscopic activity prediction was compared with that of fecal calprotectin (Fcal). RESULTS: The area under the receiver operating characteristic curve (AUC) of DLSUC for predicting endoscopic activity was 0.801 (95% confidence interval [CI] 0.717-0.873), which was not statistically different from the AUC of Fcal (0.837 [95% CI, 0.767-0.899, DeLong P = 0.458]). When rectal-sparing cases (23/126, 18.2%) were excluded, the AUC of DLSUC increased to 0.849 (95% CI, 0.760-0.919). The accuracy, sensitivity, and specificity of DLSUC in predicting endoscopic activity were 0.746, 0.662, and 0.877 in all patients and 0.845, 0.745, and 0.958 in patients without rectal sparing, respectively. Active patients classified by DLSUC were more likely to experience disease relapse during a median 8-month follow-up (log-rank test, P = 0.002). DISCUSSION: DLSUC demonstrated a good discriminating power similar to that of Fcal in predicting endoscopic activity with improved accuracy in patients without rectal sparing. This study implies that stool photographs are a useful monitoring tool for typical UC.

Application of clinical decision support tools for predicting outcomes with vedolizumab therapy in patients with inflammatory bowel disease: A KASID multicentre study.

BACKGROUND/AIM: We aimed to validate clinical decision support tools (CDSTs) to predict real-life effectiveness of vedolizumab (VDZ) in patients with inflammatory bowel disease. METHODS: We retrospectively enrolled patients with Crohn's disease (CD) or ulcerative colitis (UC) treated with VDZ at 10 tertiary referral centres in Korea between January 2017 and November 2021. We assessed clinical remission (CREM) and response (CRES), corticosteroid-free clinical remission (CSF-CREM) and response (CSF-CRES), biochemical response based on C-reactive protein (BioRES[CRP]) and faecal calprotectin (BioRES[FC]), endoscopic healing (EH), and the need to optimise or switch drugs based on CDST-defined response groups. Additionally, the area under the receiver operating characteristics curve (AUC) for the CDSTs was calculated. RESULTS: We included 143 patients with CD and 219 with UC. We observed incremental trends on CSF-CRES at week 14 (W14) (ptrend = 0.004) and decreasing trends for the need to optimise or switch drugs (ptrend = 0.016) in CD from the low to high probability groups. Except for CSF-CREM at W54, we noticed incremental trends for all clinical responses at W14, W26 and W54 (ptrend <0.001) in UC. W26 and W54 BioRES[CRP] and W14 EH also showed increasing trends (ptrend <0.05) in UC. With increasing probabilities of response, drug optimisation or switching was less frequently required in UC (ptrend = 0.013). With 26 points cut-off, CDSTs effectively identified W14 CSF-CRES, W26 BioRES[CRP], BioRES[FC] and W54 BioRES[CRP] in UC, all with AUCs >0.600, whereas CDSTs showed poor accuracy in CD. CONCLUSIONS: CDSTs for VDZ had acceptable accuracy in predicting effectiveness outcomes including clinical and biochemical outcomes in UC. However, their utility in CD was limited.

Self-screening questionnaire for perianal fistulizing disease in patients with Crohn's disease.

BACKGROUND/AIMS: A poor prognostic factor for Crohn's disease (CD) includes perianal fistulizing disease, including perianal fistula and/or perianal abscess. Currently, a tool to assess perianal symptoms in patients with CD remains nonexistent. This study aimed to develop a perianal fistulizing disease self-screening questionnaire for patients with CD. METHODS: This prospective pilot study was conducted at three tertiary referral centers between January 2019 and May 2020. We formulated questions on perianal symptoms, including tenesmus, anal discharge, bleeding, pain, and heat. A 4-point Likert scale was used to rate each question. Patients with CD completed a questionnaire and underwent pelvic magnetic resonance imaging (MRI). RESULTS: Overall, 93 patients were enrolled, with 51 (54.8%) diagnosed with perianal fistulizing disease, as determined by pelvic MRI. The Spearman correlation findings demonstrated that anal pain (p = 0.450, p < 0.001) and anal discharge (p = 0.556, p < 0.001) were the symptoms that most significantly correlated with perianal disease. For anal pain and discharge, the area under the receiver operating characteristic curve of the scores was significantly higher than that of the combined score for all five symptoms (0.855 vs. 0.794, DeLong's test p = 0.04). For the two symptoms combined, the sensitivity, specificity, and positive predictive and negative predictive values were 88.2, 73.8, 80.4, and 83.8%, respectively, with 81.7% accuracy for detecting perianal fistulizing disease. CONCLUSION: This study indicates that simple questions regarding anal pain and discharge can help accurately identify the presence of perianal fistulizing disease in patients with CD.

Mobile monitoring system detects the disease activity pattern and shows the association with clinical outcomes in patients with newly diagnosed Crohn's disease.

We aimed to determine whether Crohn's disease (CD) activity patterns assessed via a web-based symptom diary can help predict clinical outcomes in patients with newly diagnosed CD. Patients diagnosed with CD within the preceding 3 months were prospectively enrolled at four tertiary centers. All patients recorded their symptoms on a website using a smartphone at least once a week. The index outcomes were disease-related admission and surgery during follow-up. The disease activity from enrollment to outcome or last follow-up was reviewed for pattern analysis. Cox regression analysis was used to identify the predictors of disease outcomes. A total of 102 patients were enrolled. During a median follow-up period of 42 months, 25 (24.5%) and 6 (5.9%) patients required admission and surgery, respectively. Poor activity pattern was an independent predictor of disease-related hospitalization (adjusted hazard ratio [aHR], 3.96; 95% confidence interval [CI] 1.5-10.45; p = 0.005). A poor activity pattern (aHR, 19.48; 95% CI 1.86-203.95; p = 0.013) and female sex (aHR, 11.28; 95% CI 1.49-85.01; p = 0.018) were found to be independent predictors of bowel resection. CD disease activity patterns monitored through the mobile monitoring system may help predict clinical outcomes, such as disease-related hospitalization and surgery, in patients with newly diagnosed CD.

The North Equatorial Current and rapid intensification of super typhoons.

Super Typhoon Mangkhut, which traversed the North Equatorial Current (NEC; 8-17 °N) in the western North Pacific in 2018, was the most intense Category-5 tropical cyclone (TC) with the longest duration in history-3.5 days. Here we show that the combination of two factors-high ocean heat content (OHC) and increased stratification - makes the NEC region the most favored area for a rapid intensification (RI) of super typhoons, instead of the Eddy Rich Zone (17-25 °N), which was considered the most relevant for RI occurrence. The high OHC results from a northward deepening thermocline in geostrophic balance with the westward-flowing NEC. The stratification is derived from precipitation associated with the Inter-Tropical Convergence Zone in the summer peak typhoon season. These factors, which are increasingly significant over the past four decades, impede the TC-induced sea surface cooling, thus enhancing RI of TCs and simultaneously maintaining super typhoons over the NEC region.

Origin and pathway of a subsurface maximum of 137Cs detected in the winter of 2012 after the Fukushima accident.

This study investigates the dispersion behavior of 137Cs and evaluates its origin (atmospheric deposition or direct ocean release) from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident using a Lagrangian particle tracking model. The ocean circulation fields based on the Modular Ocean Model Version 5 (MOM5) were adopted for the simulation. The MOM5 results represented the formation and migration of subtropical mode water (STMW) comparable with observations and reanalysis data. Particularly, anticyclonic eddies south of the Kuroshio extension promoted surface mixing over 300 m in the cooling season. The particle tracking simulation reproduced well the maximum subsurface activity between 142 and 146°E, where STMW is deep owing to anticyclonic eddies, compared to the activity found via measurements conducted around 149°E in the winter of 2012. It also demonstrated that the 137Cs of the tropical and subtropical regions (10-35°N, 142-146°E) in the winter of 2012 almost entirely originated from atmospheric deposition.

Efficacy and safety of 1 L polyethylene glycol plus ascorbic acid for bowel preparation in elderly: comparison with oral sulfate solution.

BACKGROUND/AIMS: Recently, 1 L of polyethylene glycol (PEG) plus ascorbic acid (Asc) has been introduced in Korea as a colonoscopy preparation agent. Data on its efficacy and safety in older adults have been limited. We aimed to evaluate the safety and efficacy of 1 L PEG/Asc in older adults by comparing it with oral sulfate solution (OSS). METHODS: A prospective multicenter randomized study was conducted with subjects aged ≥ 65 years who underwent colonoscopy. The participants were randomized to receive 1 L PEG/Asc or OSS. The primary endpoint was successful bowel preparation, defined as total Boston Bowel Preparation Scale ≥ 6, and ≥ 2 at each segment. Patient satisfaction, adverse events, and renal function changes were compared between the groups. RESULTS: Among the 106 patients, 104 were finally included in the analysis. Overall, successful bowel preparation was achieved in 96.2% of both 1 L PEG/Asc and OSS groups. The satisfaction scores for taste, total amount ingested, overall feeling, and willingness to repeat the same regimen were not significantly different between the groups. Adverse events of moderate or higher severity occurred in 16 and 10 cases in the 1 L PEG/Asc and OSS group, respectively. There were no significant changes in electrolyte levels or renal function from baseline. CONCLUSION: The successful bowel preparation rate was > 90% in both groups without severe adverse effects and significant changes in renal function. As a new low-dose preparation regimen for colonoscopy in older adults, 1 L PEG/Asc, is as effective and safe as OSS.

Potential Oral Microbial Markers for Differential Diagnosis of Crohn's Disease and Ulcerative Colitis Using Machine Learning Models.

Although gut microbiome dysbiosis has been associated with inflammatory bowel disease (IBD), the relationship between the oral microbiota and IBD remains poorly understood. This study aimed to identify unique microbiome patterns in saliva from IBD patients and explore potential oral microbial markers for differentiating Crohn's disease (CD) and ulcerative colitis (UC). A prospective cohort study recruited IBD patients (UC: n = 175, CD: n = 127) and healthy controls (HC: n = 100) to analyze their oral microbiota using 16S rRNA gene sequencing. Machine learning models (sparse partial least squares discriminant analysis (sPLS-DA)) were trained with the sequencing data to classify CD and UC. Taxonomic classification resulted in 4041 phylotypes using Kraken2 and the SILVA reference database. After quality filtering, 398 samples (UC: n = 175, CD: n = 124, HC: n = 99) and 2711 phylotypes were included. Alpha diversity analysis revealed significantly reduced richness in the microbiome of IBD patients compared to healthy controls. The sPLS-DA model achieved high accuracy (mean accuracy: 0.908, and AUC: 0.966) in distinguishing IBD vs. HC, as well as good accuracy (0.846) and AUC (0.923) in differentiating CD vs. UC. These findings highlight distinct oral microbiome patterns in IBD and provide insights into potential diagnostic markers.

Vaccination in patients with inflammatory bowel disease-Asian perspectives: the results of a multinational web-based survey in the 8th Asian Organization for Crohn's and Colitis meeting.

BACKGROUND/AIMS: Long-term immunosuppressive therapies used to treat inflammatory bowel disease (IBD) are associated with an increased risk of infections, many of which can be prevented by vaccination. We assessed physicians' current approaches and clinical practices regarding vaccinations for IBD patients in different Asian countries/regions. METHODS: An internet-based survey was conducted among members of the Asian Organization for Crohn's and Colitis from September 2020 to November 2020. The questionnaire consisted of 2 parts covering general opinion on the relevance of vaccinations and clinical practice of vaccination. RESULTS: Overall, 384 Asian medical doctors responded to the survey. The majority of respondents considered it very (57.6%) or sufficiently (39.6%) important to perform vaccinations as recommended by the guidelines. About half of the Asian physicians (52.6%) were usually or always performing vaccinations. The influenza vaccine was the most frequently recommended vaccine for IBD patients. Half of the respondents (51.3%) did not recommend hepatitis A vaccine, especially in China (61.6%) and Japan (93.6%). The diphtheria, tetanus, and pertussis vaccine were never (35.2%) or rarely (29.4%) recommended. CONCLUSIONS: The findings of this survey indicated similarities among countries/regions in terms of the current approaches and practices regarding vaccination of IBD patients; however, there are some differences that might reflect each country's domestic vaccination guidelines and health insurance particularly with certain vaccines in some countries/regions. Although Asian physicians largely recommend vaccination, more awareness among doctors and Asian consensus regarding differences in IBD vaccination among countries/regions may be required.

Incidence of colonoscopy-related perforation and risk factors for poor outcomes: 3-year results from a prospective, multicenter registry (with videos).

BACKGROUND AND AIMS: Perforation is a life-threatening adverse event of colonoscopy that often requires hospitalization and surgery. We aimed to prospectively assess the incidence of colonoscopy-related perforation in a multicenter registry and to analyze the clinical factors associated with poor clinical outcomes. METHODS: This prospective observational study was conducted at six tertiary referral hospitals between 2017 and 2020, and included patients with colonic perforation after colonoscopy. Poor clinical outcomes were defined as mortality, surgery, and prolonged hospitalization (> 13 days). Logistic regression was used to identify factors associated with poor clinical outcomes. RESULTS: Among 84,673 patients undergoing colonoscopy, 56 had colon perforation (0.66/1000, 95% confidence interval [CI] 0.51-0.86). Perforation occurred in 12 of 63,602 diagnostic colonoscopies (0.19/1000, 95% CI 0.11-0.33) and 44 of 21,071 therapeutic colonoscopies (2.09/1000, 95% CI 1.55-2.81). Of these, 15 (26.8%) patients underwent surgery, and 25 (44.6%) patients had a prolonged hospital stay. One patient (1.8%) died after perforation from a diagnostic colonoscopy. In the multivariate analysis, diagnostic colonoscopy (adjusted odds ratio [aOR] 196.43, p = 0.025) and abdominal rebound tenderness (aOR 17.82, p = 0.012) were independent risk factors for surgical treatment. The location of the sigmoid colon (aOR 18.57, p = 0.048), delayed recognition (aOR 187.71, p = 0.008), and abdominal tenderness (aOR 63.20, p = 0.017) were independent risk factors for prolonged hospitalization. CONCLUSIONS: This prospective study demonstrated that the incidence of colonoscopy-related perforation was 0.66/1000. The incidence rate was higher in therapeutic colonoscopy, whereas the risk for undergoing surgery was higher in patients undergoing diagnostic colonoscopy. Colonoscopy indication (diagnostic vs. therapeutic), physical signs, the location of the sigmoid perforation, and delayed recognition were independent risk factors for poor clinical outcomes in colonoscopy-related perforation.

Real-life effectiveness and safety of tofacitinib treatment in patients with ulcerative colitis: a KASID multicenter cohort study.

Background: Tofacitinib is a small molecule that inhibits Janus kinase and has been reported to be effective in Western patients with ulcerative colitis (UC). However, the real-life data on tofacitinib in Asian UC patients are limited. Objective: To investigate the real-life effectiveness and safety of tofacitinib induction and maintenance treatment in Korean patients with UC. Design: This was a retrospective study on patients with UC who received tofacitinib treatment at 12 hospitals in Korea between January 2018 and November 2020. Methods: Clinical remission at week 52, defined as a partial Mayo score of ⩽2 with a combined rectal bleeding subscore and stool frequency subscore of ⩽1, was used as the primary outcome. Adverse events (AEs), including herpes zoster and deep vein thrombosis, were also evaluated. Results: A total of 148 patients with UC were started on tofacitinib. Clinical remission rates of 60.6%, 54.9%, and 52.8% were reported at weeks 16, 24, and 52, respectively. Clinical response rates of 71.8%, 67.6%, and 59.9% were reported at weeks 16, 24, and 52, respectively. Endoscopic remission rates at weeks 16 and 52 were 52.4% and 30.8% based on the Mayo endoscopic subscore and 20.7% and 15.2% based on the UC endoscopic index of severity (UCEIS), respectively. A higher UCEIS at baseline was negatively associated with clinical response [adjusted odds ratio (aOR): 0.774, p = 0.029] and corticosteroid-free clinical response (aOR: 0.782, p = 0.035) at week 52. AEs occurred in 19 patients (12.8%) and serious AEs in 12 patients (8.1%). Herpes zoster occurred in four patients (2.7%). One patient (0.7%) suffered from deep vein thrombosis. Conclusions: Tofacitinib was an effective induction and maintenance treatment with an acceptable safety profile in Korean patients with UC. Plain language summary: Real-life effectiveness and safety of tofacitinib treatment in Korean patients with ulcerative colitis Ulcerative colitis (UC) is an idiopathic, chronic inflammatory disorder of the colonic mucosa that usually presents with bloody diarrhea and abdominal pain. Tofacitinib is a small molecule that inhibits Janus kinase and has been reported to be effective in Western patients with UC. However, real-life data on the effectiveness of tofacitinib in Asian patients with UC are limited. To investigate the real-life effectiveness and safety of tofacitinib treatment in Korean patients with UC, we retrospectively analyzed the data of 148 patients with UC who received tofacitinib treatment at 12 hospitals in Korea between January 2018 and November 2020. Clinical remission (i.e. complete improvement of symptoms) was achieved in 60.6% and 52.8% of patients at weeks 16 and 52, respectively. Endoscopic remission was achieved in 52.4% and 30.8% of patients at weeks 16 and 52, respectively. A higher baseline score of the UC endoscopic index of severity, which is one of the endoscopic indices that evaluate the severity of inflammation of the colon, was negatively associated with clinical response (i.e. partial improvement of symptoms). Adverse events (AEs) including herpes zoster and deep vein thrombosis occurred in 19 patients (12.8%) and serious AEs occurred in 12 patients (8.1%). Our real-life study shows that tofacitinib is a clinically effective treatment for Korean patients with UC, and the incidence of AEs was also similar to those observed in other real-world studies.

Clean mucosal area detection of gastroenterologists versus artificial intelligence in small bowel capsule endoscopy.

Studies comparing the detection of clean mucosal areas in capsule endoscopy (CE) using human judgment versus artificial intelligence (AI) are rare. This study statistically analyzed gastroenterologist judgments and AI results. Three hundred CE video clips (100 patients) were prepared. Five gastroenterologists classified the video clips into 3 groups (≥75% [high], 50%-75% [middle], and < 50% [low]) according to their subjective judgment of cleanliness. Visualization scores were calculated using an AI algorithm based on the predicted visible area, and the 5 gastroenterologists' judgments and AI results were compared. The 5 gastroenterologists evaluated CE clip video quality as "high" in 10.7% to 36.7% and as "low" in 28.7% to 60.3% and 29.7% of cases, respectively. The AI evaluated CE clip video quality as "high" in 27.7% and as "low" in 29.7% of cases. Repeated-measures analysis of variance (ANOVA) revealed significant differences in the 6 evaluation indicators (5 gastroenterologists and 1 AI) (P < .001). Among the 300 judgments, 90 (30%) were consistent with 5 gastroenterologists' judgments, and 82 (91.1%) agreed with the AI judgments. The "high" and "low" judgments of the gastroenterologists and AI agreed in 95.0% and 94.9% of cases, respectively. Bonferroni's multiple comparison test showed no significant difference between 3 gastroenterologists and AI (P = .0961, P = 1.0000, and P = .0676, respectively) but a significant difference between the other 2 with AI (P < .0001). When evaluating CE images for cleanliness, the judgments of 5 gastroenterologists were relatively diverse. The AI produced a relatively universal judgment that was consistent with the gastroenterologists' judgements.

Korean clinical practice guidelines on biologics for moderate to severe Crohn's disease.

Crohn's disease (CD) is a relapsing and progressive condition characterized by diarrhea, abdominal pain, weight loss, and hematochezia that results in serious complications such as perforations, fistulas, and abscesses. Various medications, interventions, and surgical treatments have been used to treat CD. The Korean guidelines for CD management were distributed in 2012 and revised in 2017 by the Inflammatory Bowel Disease (IBD) Research Group of the Korean Association for the Study of Intestinal Diseases. Substantial progress in mucosal immunologic research has elucidated the pathophysiology of IBD, leading to development of biological agents for treatment of CD. The first developed biologic agent, tumor necrosis factor-α agents, were shown to be efficacious in CD, heralding a new era in management of CD. Subsequently, vedolizumab, a monoclonal antibody against integrin α4ß7, and ustekinumab, a human monoclonal antibody that inhibits the common p40 subunit of interleukin-12 and interleukin-23, were both approved for clinical use and are efficacious and safe for both induction and maintenance of remission in moderate-to-severe CD patients. Moreover, a recent study showed the non-inferiority of CT-P13, an infliximab biosimilar, compared with infliximab in CD patients. The third Korean guidelines for CD management provide updated information regarding treatment of moderate-to-severe CD patients with biologic agents.

The Prognostic Utilities of DNA Mismatch Repair Status and KRAS and BRAF Mutation in Korean Colorectal Cancer Patients: The KASID Multicenter Study.

INTRODUCTION: KRAS, BRAF, and DNA mismatch repair (MMR) mutations aid clinical decision-making for colorectal cancer (CRC) patients. To ensure accurate predictions, the prognostic utilities of these biomarkers and their combinations must be individualized for patients with various TNM stages. METHODS: Here, we retrospectively analyzed the clinicopathological features of 904 Korean CRC patients who underwent CRC surgery in three teaching hospitals from 2011 to 2013; we also assessed the prognostic utilities of KRAS, BRAF, and MMR mutations in these patients. RESULTS: The overall frequencies of KRAS and BRAF mutations were 35.8% and 3.2%, respectively. Sixty-nine patients (7.6%) lacking expression of ≥1 MMR protein were considered MMR protein deficient (MMR-D); the remaining patients were considered MMR protein intact. KRAS mutations constituted an independent risk factor for shorter overall survival (OS) in TNM stage I-IV and stage III patients. BRAF mutations were associated with shorter OS in TNM stage I-IV patients. MMR-D status was strongly positive prognostic in TNM stage I-II patients. DISCUSSION/CONCLUSION: To our knowledge, this is the first multicenter study to explore the prognostic utilities of KRAS, BRAF, and MMR statuses in Korean CRC patients. Various combinations of KRAS, BRAF, and DNA MMR mutations serve as genetic signatures that affect tumor behavior; they are prognostic in CRC patients.

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. In those patients diagnosed with cancer, data obtained included the date of cancer diagnosis, the tumor location, and the cancer stage. The cumulative risks of gastrointestinal cancers and extra-gastrointestinal cancers were calculated using the Kaplan-Meier method. RESULTS: A total of 96 PJS patients were included. The median age at diagnosis of PJS was 23.4 years. Cancer developed in 21 of the 96 patients (21.9%). The age of PJS diagnosis was widely distributed (0.9 to 72.4 years). The most common cancers were gastrointestinal cancer (n = 12) followed by breast cancer (n = 6). The cumulative lifetime cancer risk was calculated to be 62.1% at age 60. The cumulative lifetime gastrointestinal cancer risk was 47.1% at age 70. The cumulative lifetime extra- gastrointestinal cancer risk was 40.3% at age 60. CONCLUSION: PJS onset may occur at any age and the risks of gastrointestinal and extra-gastrointestinal cancer are high. Thorough surveillance of PJS patients for malignancies is vital.

A Machine Learning-Based Diagnostic Model for Crohn's Disease and Ulcerative Colitis Utilizing Fecal Microbiome Analysis.

Recent research has demonstrated the potential of fecal microbiome analysis using machine learning (ML) in the diagnosis of inflammatory bowel disease (IBD), mainly Crohn's disease (CD) and ulcerative colitis (UC). This study employed the sparse partial least squares discriminant analysis (sPLS-DA) ML technique to develop a robust prediction model for distinguishing among CD, UC, and healthy controls (HCs) based on fecal microbiome data. Using data from multicenter cohorts, we conducted 16S rRNA gene sequencing of fecal samples from patients with CD (n = 671) and UC (n = 114) while forming an HC cohort of 1462 individuals from the Kangbuk Samsung Hospital Healthcare Screening Center. A streamlined pipeline based on HmmUFOTU was used. After a series of filtering steps, 1517 phylotypes and 1846 samples were retained for subsequent analysis. After 100 rounds of downsampling with age, sex, and sample size matching, and division into training and test sets, we constructed two binary prediction models to distinguish between IBD and HC and CD and UC using the training set. The binary prediction models exhibited high accuracy and area under the curve (for differentiating IBD from HC (mean accuracy, 0.950; AUC, 0.992) and CD from UC (mean accuracy, 0.945; AUC, 0.988)), respectively, in the test set. This study underscores the diagnostic potential of an ML model based on sPLS-DA, utilizing fecal microbiome analysis, highlighting its ability to differentiate between IBD and HC and distinguish CD from UC.