Background: s/Aims: Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021. Methods: Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop. Results: In November 2021, the finalized draft was presented for public scrutiny during a formal hearing. Conclusions The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Continuous renal replacement therapy (CRRT) has become the standard modality of renal replacement therapy (RRT) in critically ill patients. However, consensus is lacking regarding the criteria for discontinuing CRRT. Here we validated the usefulness of the prediction model for successful discontinuation of CRRT in a multicenter retrospective cohort. Methods: One temporal cohort and four external cohorts included 1,517 patients with acute kidney injury who underwent CRRT for >2 days from 2018 to 2020. The model was composed of four variables: urine output, blood urea nitrogen, serum potassium, and mean arterial pressure. Successful discontinuation of CRRT was defined as the absence of an RRT requirement for 7 days thereafter. Results: The area under the receiver operating characteristic curve (AUROC) was 0.74 (95% confidence interval, 0.71–0.76). The probabilities of successful discontinuation were approximately 17%, 35%, and 70% in the low-score, intermediate-score, and highscore groups, respectively. The model performance was good in four cohorts (AUROC, 0.73–0.75) but poor in one cohort (AUROC, 0.56). In one cohort with poor performance, attending physicians primarily controlled CRRT prescription and discontinuation, while in the other four cohorts, nephrologists determined all important steps in CRRT operation, including screening for CRRT discontinuation. Conclusion: The overall performance of our prediction model using four simple variables for successful discontinuation of CRRT was good, except for one cohort where nephrologists did not actively engage in CRRT operation. These results suggest the need for active engagement of nephrologists and protocolized management for CRRT discontinuation.

Purpose: Renal tumors account for approximately 7% of all childhood cancers. These include Wilms tumor (WT), clear cell sarcoma of the kidney (CCSK), malignant rhabdoid tumor of the kidney (MRTK), renal cell carcinoma (RCC), congenital mesoblastic nephroma (CMN) and other rare tumors. We investigated the epidemiology of pediatric renal tumors in Korea. Materials and Methods: From January 2001 to December 2015, data of pediatric patients (0–18 years) newly-diagnosed with renal tumors at 26 hospitals were retrospectively analyzed. Results: Among 439 patients (male, 240), the most common tumor was WT (n=342, 77.9%), followed by RCC (n=36, 8.2%), CCSK (n=24, 5.5%), MRTK (n=16, 3.6%), CMN (n=12, 2.7%), and others (n=9, 2.1%). Median age at diagnosis was 27.1 months (range 0-225.5) and median follow-up duration was 88.5 months (range 0-211.6). Overall, 32 patients died, of whom 17, 11, 1, and 3 died of relapse, progressive disease, second malignant neoplasm, and treatment-related mortality. Five-year overall survival and event free survival were 97.2% and 84.8% in WT, 90.6% and 82.1% in RCC, 81.1% and 63.6% in CCSK, 60.3% and 56.2% in MRTK, and 100% and 91.7% in CMN, respectively (p < 0.001). Conclusion The pediatric renal tumor types in Korea are similar to those previously reported in other countries. WT accounted for a large proportion and survival was excellent. Non-Wilms renal tumors included a variety of tumors and showed inferior outcome, especially MRTK. Further efforts are necessary to optimize the treatment and analyze the genetic characteristics of pediatric renal tumors in Korea.

Objective: We aimed to present the study design and baseline cross-sectional participant characteristics of biobank innovations for chronic cerebrovascular disease with Alzheimer’s disease study (BICWALZS) participants. Methods: A total of 1,013 participants were enrolled in BICWALZS from October 2016 to December 2020. All participants underwent clinical assessments, basic blood tests, and standardized neuropsychological tests (n=1,013). We performed brain magnetic resonance imaging (MRI, n=817), brain amyloid positron emission tomography (PET, n=713), single nucleotide polymorphism microarray chip (K-Chip, n=949), locomotor activity assessment (actigraphy, n=200), and patient-derived dermal fibroblast sampling (n=175) on a subset of participants. Results: The mean age was 72.8 years, and 658 (65.0%) were females. Based on clinical assessments, total of 168, 534, 211, 80, and 20 had subjective cognitive decline, mild cognitive impairment (MCI), Alzheimer’s dementia, vascular dementia, and other types of dementia or not otherwise specified, respectively. Based on neuroimaging biomarkers and cognition, 199, 159, 78, and 204 were cognitively normal (CN), Alzheimer’s disease (AD)-related cognitive impairment, vascular cognitive impairment, and not otherwise specified due to mixed pathology (NOS). Each group exhibited many differences in various clinical, neuropsychological, and neuroimaging results at baseline. Baseline characteristics of BICWALZS participants in the MCI, AD, and vascular dementia groups were generally acceptable and consistent with 26 worldwide dementia cohorts and another independent AD cohort in Korea. Conclusion The BICWALZS is a prospective and longitudinal study assessing various clinical and biomarker characteristics in older adults with cognitive complaints. Details of the recruitment process, methodology, and baseline assessment results are described in this paper.

The accuracy and convenience of continuous glucose monitoring (CGM), which efficiently evaluates glycemic variability and hypoglycemia, are improving. There are two types of CGM: professional CGM and personal CGM. Personal CGM is subdivided into real-time CGM (rt-CGM) and intermittently scanned CGM (isCGM). CGM is being emphasized in both domestic and foreign diabetes management guidelines. Regardless of age or type of diabetes, CGM is useful for diabetic patients undergoing multiple insulin injection therapy or using an insulin pump. rt-CGM is recommended for all adults with type 1 diabetes (T1D), and can also be used in type 2 diabetes (T2D) treatments using multiple insulin injections. In some cases, short-term or intermittent use of CGM may be helpful for patients with T2D who use insulin therapy other than multiple insulin injections and/or oral hypoglycemic agents. CGM can help to achieve A1C targets in diabetes patients during pregnancy. CGM is a safe and cost-effective alternative to self-monitoring blood glucose in T1D and some T2D patients. CGM used in diabetes management works optimally with proper education, training, and follow up. To achieve the activation of CGM and its associated benefits, it is necessary to secure sufficient repetitive training and time for data analysis, management, and education. Various supports such as compensation, insurance coverage expansion, and reimbursement are required to increase the effectiveness of CGM while considering the scale of benefit recipients, policy priorities, and financial requirements.

Background: Recently, a metabolic syndrome severity score (MS score) using a dataset of the Korea National Health and Nutrition Examination Surveys has been developed. We aimed to determine whether the newly developed score is a significant predictor of cardiovascular (CV) events among the Korean population. Methods: From the Korean National Health Insurance System, 2,541,364 (aged 40 to 59 years) subjects with no history of CV events (ischemic stroke or myocardial infarction [MI]), who underwent health examinations from 2009 to 2011 and were followed up until 2014 to 2017, were identified. Cox proportional hazard model was employed to investigate the association between MS score and CV events. Model performance of MS score for predicting CV events was compared to that of conventional metabolic syndrome diagnostic criteria (Adult Treatment Program III [ATP-III]) using the Akaike information criterion and the area under the receiver operating characteristic curve. Results: Over a median follow-up of 6 years, 15,762 cases of CV events were reported. MS score at baseline showed a linear association with incident CV events. In the multivariable-adjusted model, the hazard ratios (95% confidence intervals) comparing the highest versus lowest quartiles of MS score were 1.48 (1.36 to 1.60) for MI and 1.89 (1.74 to 2.05) for stroke. Model fitness and performance of the MS score in predicting CV events were superior to those of ATP-III. Conclusion The newly developed age- and sex-specific continuous MS score for the Korean population is an independent predictor of ischemic stroke and MI in Korean middle-aged adults even after adjusting for confounding factors.

Background: Recently, a metabolic syndrome severity score (MS score) using a dataset of the Korea National Health and Nutrition Examination Surveys has been developed. We aimed to determine whether the newly developed score is a significant predictor of cardiovascular (CV) events among the Korean population. Methods: From the Korean National Health Insurance System, 2,541,364 (aged 40 to 59 years) subjects with no history of CV events (ischemic stroke or myocardial infarction [MI]), who underwent health examinations from 2009 to 2011 and were followed up until 2014 to 2017, were identified. Cox proportional hazard model was employed to investigate the association between MS score and CV events. Model performance of MS score for predicting CV events was compared to that of conventional metabolic syndrome diagnostic criteria (Adult Treatment Program III [ATP-III]) using the Akaike information criterion and the area under the receiver operating characteristic curve. Results: Over a median follow-up of 6 years, 15,762 cases of CV events were reported. MS score at baseline showed a linear association with incident CV events. In the multivariable-adjusted model, the hazard ratios (95% confidence intervals) comparing the highest versus lowest quartiles of MS score were 1.48 (1.36 to 1.60) for MI and 1.89 (1.74 to 2.05) for stroke. Model fitness and performance of the MS score in predicting CV events were superior to those of ATP-III. Conclusion The newly developed age- and sex-specific continuous MS score for the Korean population is an independent predictor of ischemic stroke and MI in Korean middle-aged adults even after adjusting for confounding factors.

Purpose: Fluorodeoxyglucose positron emission tomography–computed tomography (PET-CT) is gaining evidence as a predictive factor in non-small cell lung cancer (NSCLC). Stereotactic ablative radiotherapy (SABR) is the standard treatment in early-stage NSCLC when a patient is unsuitable for surgery. We performed a study to assess the prognostic clinical significance of PET-CT after SABR in early-stage NSCLC. Materials and Methods: Seventy-six patients with stage I NSCLC treated with SABR were investigated. Total radiation dose ranged from 36 to 63 Gy in three to eight fractions depending on tumor location and size. Respiratory motion control was implemented at simulation and during treatment. PET-CT prior to SABR was performed in 66 patients (86.8%). Results: Median follow-up time was 32 months (range, 5 to 142 months). Local control rate at 1, 2, and 5 years were 95.9%, 92.8%, and 86.7%, respectively. Overall survival (OS) at 1, 2, and 5 years were 91.0%, 71.3%, and 52.1% respectively. Cause-specific survival at 1, 2, and 5 years were 98.6%, 93.1%, and 84.3% respectively. Tumor size and pre-SABR maximal standardized uptake value (SUVmax) demonstrated statistical significance in the Kaplan-Meier survival analyses with log-rank test. In multivariate analyses pre-SABR SUVmax remained statistically significant in correlation to OS (p=0.024; hazard ratio [HR], 3.2; 95% confidence interval [CI], 1.2 to 8.8) and with marginal significance in regards to regional progression-free survival (p=0.059; HR, 32.5; 95% CI, 2.6 to 402.5). Conclusion Pre-SABR SUVmax demonstrated a predictive power in statistical analyses. Tumors with SUVmax above 6 at diagnosis were associated with inferior outcomes.

Background: Hereditary hemolytic anemia (HHA) is a rare disease characterized by premature red blood cell (RBC) destruction due to intrinsic RBC defects. The RBC Disorder Working Party of the Korean Society of Hematology established and updated the standard operating procedure for making an accurate diagnosis of HHA since 2007. The aim of this study was to investigate a nationwide epidemiology of Korean HHA. Methods: We collected the data of a newly diagnosed pediatric HHA cohort (2007–2016) and compared this cohort's characteristics with those of a previously surveyed pediatric HHA cohort (1997–2006) in Korea. Each participant's information was retrospectively collected by a questionnaire survey. Results: A total of 369 children with HHA from 38 hospitals distributed in 16 of 17 districts of Korea were investigated. RBC membranopathies, hemoglobinopathies, RBC enzymopathies, and unknown etiologies accounted for 263 (71.3%), 59 (16.0%), 23 (6.2%), and 24 (6.5%) of the cases, respectively. Compared to the cohort from the previous decade, the proportions of hemoglobinopathies and RBC enzymopathies significantly increased (P < 0.001 and P = 0.008, respectively). Twenty-three of the 59 hemoglobinopathy patients had immigrant mothers, mostly from South-East Asia. Conclusion In Korea, thalassemia traits have increased over the past 10 years, reflecting both increased awareness of this disease and increased international marriages. The enhanced recognition of RBC enzymopathies is due to advances in diagnostic technique; however, 6.5% of HHA patients still do not have a clear diagnosis. It is necessary to improve accessibility of diagnosing HHA.

BACKGROUND: Continuous metabolic syndrome (MS) severity scores that can track metabolic risk in individuals over time have been developed for Western populations. The present study aimed to develop gender- and age-specific equations for MS severity scores in Korean adults. METHODS: Using data from the Korea National Health and Nutrition Examination Surveys (KNHANES) IV (2010–2012) and VI (2013–2015), we performed a confirmatory factor analysis of single MS factor that allowed for differential loadings across groups to generate gender- and age-specific, continuous MS severity scores. Then, we validated this equation in a different dataset of Korean adults. RESULTS: In confirmatory analysis, waist circumference had the highest factor loading, indicating that waist circumference had the strongest correlation with MS among Korean adults. Lower factor loadings (< 0.4) among Korean adults aged 40–59 years were noted for systolic blood pressure and fasting glucose. MS severity score values were significantly correlated with metabolic parameters, including high-sensitivity C-reactive-protein, glycated hemoglobin, and homeostasis model assessment of insulin resistance. Furthermore, MS severity scores well predicted traditional MS according to receiver operating characteristic analysis in a validation dataset (KNHANES VII). In a longitudinal cohort dataset, participants diagnosed with Adult Treatment Program III (ATP-III) MS after an initial assessment had progressively higher baseline MS severity scores in relationship to their time until ATP-III MS diagnosis. CONCLUSION: The new MS severity score equations for Korean adults proposed in this study provide a clinically-accessible continuous measure of MS for potential use in identifying adults at higher risk for MS-related diseases and following changes within individuals over time.
Adult ; Blood Pressure ; Cohort Studies ; Dataset ; Diagnosis ; Epidemiology ; Fasting ; Glucose ; Hemoglobin A, Glycosylated ; Homeostasis ; Humans ; Insulin Resistance ; Korea ; Nutrition Surveys ; Obesity ; ROC Curve ; Waist Circumference