Background/Aims: Endoscopic anti-reflux therapy is a therapeutic option for gastroesophageal reflux disease (GERD), providing durable effects. However, clinical data from Korea remain limited. This study evaluates the clinical outcomes of endoscopic radiofrequency Stretta therapy in Korean patients. Methods: A retrospective analysis was conducted on 71 patients with GERD who underwent Stretta therapy at 2 tertiary hospitals in Korea between November 2015 and July 2021. Clinical outcomes, including patient satisfaction, medication cessation or reduction, and complications, were evaluated. Pre- and post-procedural esophageal manometry and 24-hour pH monitoring test results were also analyzed. Results: Patient satisfaction rates at 1, 6, and 12 months post-procedure were 54.7% (35/64), 70.0% (28/40), and 75.0% (21/28), respectively. Medication cessation or reduction was achieved in 31.2% (20/64) at 1 month, 70.0% (28/40) at 6 months, and 67.9% (19/28) at 12 months. Esophageal manometry (n = 21) showed no significant changes in mean lower esophageal sphincter pressure (18.7 mmHg [2.5-52.9] vs 17.4 mmHg [0.0-43.0], P = 0.702) or mean integrated relaxation pressure (8.2 mmHg [0.0-28.0] vs 10.1 mmHg [0.0-31.0], P = 0.840). The 24-hour pH monitoring (n = 18) demonstrated a nonsignificant decrease in acid exposure time (pH < 4) from 2.3% (0.0-8.4) to 1.6% (0.0-7.3) (P = 0.182). Similarly, the DeMeester score decreased non-significantly from 8.4 (0.8-27.7) to 6.6 (0.8-21.8) (P = 0.352). No procedure-related complications occurred. Conclusion Endoscopic radiofrequency Stretta therapy appears to be a safe treatment option for GERD and may provide favorable patient satisfaction and medication reduction.

Limited data exist regarding the real-world practices and clinical outcomes in patients with ischemic heart failure with reduced left ventricular ejection fractions (LVEFs).Using nationwide registry data from South Korea, we aimed to investigate long-term outcomes and clinical practices, especially implantable cardioverter defibrillators (ICDs) implantation, in patients with reduced LVEFs at least 40 days after acute myocardial infarction (AMI). Of 13,056 patients with AMI between 2011 and 2015, we analyzed 350 (median age, 66 years [interquartile range, 56-75]) who had LVEFs <40% on follow-up transthoracic echocardiogram 40 days after the index event. The primary outcome was cardiac-cause mortality at 3 years. Secondary outcomes comprised major cardiovascular events as well as outcomes defined by the use of ICDs, cardiac resynchronization therapy defibrillators (CRT-Ds), and electrophysiology studies. Among 350 patients, 39 (11.1%) died from cardiac causes during 3 years of follow-up. Eleven (3.1%) were hospitalized for ventricular tachycardia. The rate of ICD or CRT-D implantation up to 3 years was 5.7% (20/350). Cox time-to-event analysis revealed older age, LVEF <30%, diabetes mellitus, and previous MI or revascularization as positively associated with cardiac death, whereas the use of statins and body weight <67 kg were negatively associated. This nationwide Korean registry demonstrated that only 5.7% of patients who had reduced LVEFs after 40 days of AMI underwent ICD implantations over 3 years. Considering the high mortality, concerted efforts are needed to improve clinical outcomes for patients who may have been candidates for ICD implantation.

Purpose: Radiotherapy (RT) remains a cornerstone of curative treatment for localized and locally advanced prostate cancer. However, dose escalation to improve tumor control is often constrained by the proximity of the rectum, which increases the risk of gastrointestinal (GI) and genitourinary toxicities. Biodegradable rectal spacers inserted between the prostate and rectum have emerged as an effective approach to reduce rectal radiation exposure. This guideline provides evidence-based recommendations on indications, contraindications, procedural standards, and clinical management for biodegradable rectal spacer insertion during prostate cancer RT. Materials and Methods: This guideline was developed by a multidisciplinary expert panel through a systematic review of the literature, analysis of international guidelines (National Comprehensive Cancer Network, European Association of Urology, American Society for Radiation Oncology), and expert consensus among radiation oncologists, radiologists, and urologists with clinical experience in spacer insertion. The strength of each recommendation and the level of evidence were classified according to the modified GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system. Results: Spacer insertion is conditionally recommended (Grade C, Level I) for patients receiving definitive external-beam RT without rectal invasion. It reduces the high-dose rectal irradiation volume (V70–75) by >50%, decreases acute GI toxicity, and helps maintain bowel-related quality of life. However, the benefit for late severe toxicity (grade 2 or higher) remains debated in recent meta-analyses. Contraindications include rectal invasion, anatomical inaccessibility, infection, and material hypersensitivity. Procedures should be performed under local anesthesia in a sterile environment by trained physicians. Short-course antibiotics and simulator-based training, including completion of multiple supervised cases, are advised. Conclusion Biodegradable rectal spacer insertion is clinically validated and effective in reducing acute rectal toxicity. Although pivotal trials demonstrated a favorable procedural safety profile, real-world postmarket data include reports of rare but severe procedural complications. This guideline provides standardized recommendations tailored to Korean clinical practice while remaining consistent with international standards, emphasizing the importance of operator training and careful patient selection.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Gastric cancer is one of the most common cancers in both Korea and worldwide. Since 2004, the Korean Practice Guidelines for Gastric Cancer have been regularly updated, with the 4th edition published in 2022. The 4th edition was the result of a collaborative work by an interdisciplinary team, including experts in gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology, and guideline development methodology. The current guideline is the 5th version, an updated version of the 4th edition. In this guideline, 6 key questions (KQs) were updated or proposed after a collaborative review by the working group, and 7 statements were developed, or revised, or discussed based on a systematic review using the MEDLINE, Embase, Cochrane Library, and KoreaMed database. Over the past 2 years, there have been significant changes in systemic treatment, leading to major updates and revisions focused on this area.Additionally, minor modifications have been made in other sections, incorporating recent research findings. The level of evidence and grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation system. Key factors for recommendation included the level of evidence, benefit, harm, and clinical applicability. The working group reviewed and discussed the recommendations to reach a consensus. The structure of this guideline remains similar to the 2022 version.Earlier sections cover general considerations, such as screening, diagnosis, and staging of endoscopy, pathology, radiology, and nuclear medicine. In the latter sections, statements are provided for each KQ based on clinical evidence, with flowcharts supporting these statements through meta-analysis and references. This multidisciplinary, evidence-based gastric cancer guideline aims to support clinicians in providing optimal care for gastric cancer patients.

Objective: : Patients with traumatic brain injury (TBI) commonly exhibit a poor mental health status and can easily develop aspiration pneumonia. Thus, early proper nutrition through oral or tube feeding is difficult to achieve, leading to malnutrition. However, evidence regarding early nutritional support in the intensive care unit (ICU) is lacking. We aimed to assess the effect of early nutrition in patients with TBI admitted to the ICU. Methods: : Data of adult patients with TBI admitted to the trauma ICU of a regional trauma center in Korea between 2022 and 2023 were retrospectively analyzed. Those with ICU stay <7 days, younger than 18 years, and with underlying diseases that could alter baseline metabolism, were excluded. Nutritional support on day 4 of ICU admission was measured. The patients were classified into mortality and survival groups, and risk factors for mortality were evaluated. Subgroup analyses were performed based on TBI severity. Results: : Overall, 864 patients were diagnosed with acute TBI, of whom 227 were included in this study. The mortality rate in the study population was 15% (n=34). Those in the survival group were younger, had longer hospital stays, had a higher initial Glasglow coma scale (GCS) score, and had a higher intake of calorie supplements than those in the mortality group. In a subgroup analysis of patients with non-severe TBI (GCS >8), total calorie intake (751.4 vs. 434.2 kcal, p=0.029), total protein intake (37.5 vs. 22.1 g, p=0.045), and ratio of supplied to target calories (0.49 vs. 0.30, p=0.047) were higher in the survival group than in the mortality group. Logistic regression analysis revealed that calorie intake (B=-0.002, p=0.040) and initial hemoglobin level (B=-0.394, p=0.005) were risk factors for mortality in patients with non-severe TBI. Conclusion : More calories were supplied to the survival group than the mortality group among patients with TBI. Additionally, logistic regression analysis showed that increased calorie supply was associated with reduced mortality in patients with non-severe TBI. The mortality group had low protein intake; however, this did not emerge as a risk factor for mortality. Early sufficient nutritional support improves the prognosis of patients with TBI.

Neuronal intranuclear inclusion disease (NIID) is a rare neurodegenerative disorder characterized by the presence of eosinophilic nuclear inclusions in neurons and somatic cells. It clinically manifests as cognitive decline, seizures, and autonomic dysfunction. A 44-year-old man presented with a transient visual field defect and hemiparesis. Based on characteristic imaging findings and pathological findings, NIID was suspected and diagnosed through genetic testing. This case emphasizes the importance of comprehensive clinical phenotype analysis and accurate genetic diagnosis.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Neuronal intranuclear inclusion disease (NIID) is a rare neurodegenerative disorder characterized by the presence of eosinophilic nuclear inclusions in neurons and somatic cells. It clinically manifests as cognitive decline, seizures, and autonomic dysfunction. A 44-year-old man presented with a transient visual field defect and hemiparesis. Based on characteristic imaging findings and pathological findings, NIID was suspected and diagnosed through genetic testing. This case emphasizes the importance of comprehensive clinical phenotype analysis and accurate genetic diagnosis.

Objective: : Patients with traumatic brain injury (TBI) commonly exhibit a poor mental health status and can easily develop aspiration pneumonia. Thus, early proper nutrition through oral or tube feeding is difficult to achieve, leading to malnutrition. However, evidence regarding early nutritional support in the intensive care unit (ICU) is lacking. We aimed to assess the effect of early nutrition in patients with TBI admitted to the ICU. Methods: : Data of adult patients with TBI admitted to the trauma ICU of a regional trauma center in Korea between 2022 and 2023 were retrospectively analyzed. Those with ICU stay <7 days, younger than 18 years, and with underlying diseases that could alter baseline metabolism, were excluded. Nutritional support on day 4 of ICU admission was measured. The patients were classified into mortality and survival groups, and risk factors for mortality were evaluated. Subgroup analyses were performed based on TBI severity. Results: : Overall, 864 patients were diagnosed with acute TBI, of whom 227 were included in this study. The mortality rate in the study population was 15% (n=34). Those in the survival group were younger, had longer hospital stays, had a higher initial Glasglow coma scale (GCS) score, and had a higher intake of calorie supplements than those in the mortality group. In a subgroup analysis of patients with non-severe TBI (GCS >8), total calorie intake (751.4 vs. 434.2 kcal, p=0.029), total protein intake (37.5 vs. 22.1 g, p=0.045), and ratio of supplied to target calories (0.49 vs. 0.30, p=0.047) were higher in the survival group than in the mortality group. Logistic regression analysis revealed that calorie intake (B=-0.002, p=0.040) and initial hemoglobin level (B=-0.394, p=0.005) were risk factors for mortality in patients with non-severe TBI. Conclusion : More calories were supplied to the survival group than the mortality group among patients with TBI. Additionally, logistic regression analysis showed that increased calorie supply was associated with reduced mortality in patients with non-severe TBI. The mortality group had low protein intake; however, this did not emerge as a risk factor for mortality. Early sufficient nutritional support improves the prognosis of patients with TBI.