Background: and Purpose We aimed to determine the proportion of Korean patients with early Alzheimer’s disease (AD) who are eligible to receive lecanemab based on the United States Appropriate Use Recommendations (US AUR), and also identify the barriers to this treatment. Methods: We retrospectively enrolled 6,132 patients with amnestic mild cognitive impairment or mild amnestic dementia at 13 hospitals from June 2023 to May 2024. Among them, 2,058 patients underwent amyloid positron emission tomography (PET) and 1,199 (58.3%) of these patients were amyloid-positive on PET. We excluded 732 patients who did not undergo brain magnetic resonance imaging between June 2023 and May 2024. Finally, 467 patients were included in the present study. Results: When applying the criteria of the US AUR, approximately 50% of patients with early AD were eligible to receive lecanemab treatment. Among the 467 included patients, 36.8% did not meet the inclusion criterion of a Mini-Mental State Examination (MMSE) score of ≥22. Conclusions Eligibility for lecanemab treatment was not restricted to Korean patients with early AD except for those with an MMSE score of ≥22. The MMSE criteria should therefore be reconsidered in areas with a higher proportion of older people, who tend to have lower levels of education.

Purpose: Since 1995, the Korean Gastric Cancer Association (KGCA) has been periodically conducting nationwide surveys on patients with surgically treated gastric cancer. This study details the results of the survey conducted in 2023. Materials and Methods: The survey was conducted from March to December 2024 using a standardized case report form. Data were collected on 86 items, including patient demographics, tumor characteristics, surgical procedures, and surgical outcomes. The results of the 2023 survey were compared with those of previous surveys. Results: Data from 12,751 cases were collected from 66 institutions. The mean patient age was 64.6 years, and the proportion of patients aged ≥71 years increased from 9.1% in 1995 to 31.7% in 2023. The proportion of upper-third tumors slightly decreased to 16.8% compared to 20.9% in 2019. Early gastric cancer accounted for 63.1% of cases in 2023.Regarding operative procedures, a totally laparoscopic approach was most frequently applied (63.2%) in 2023, while robotic gastrectomy steadily increased to 9.5% from 2.1% in 2014.The most common anastomotic method was the Billroth II procedure (48.8%) after distal gastrectomy and double-tract reconstruction (51.9%) after proximal gastrectomy in 2023.However, the proportion of esophago-gastrostomy with anti-reflux procedures increased to 30.9%. The rates of post-operative mortality and overall complications were 1.0% and 15.3%, respectively. Conclusions The results of the 2023 nationwide survey demonstrate the current status of gastric cancer treatment in Korea. This information will provide a basis for future gastric cancer research.

This review provides a comprehensive framework for the diagnostic approach and management of Huntington’s disease (HD) tailored to the Korean population. Key topics include genetic counseling, predictive testing, and reproductive options like preimplantation genetic testing. Strategies for assessing disease progression in premanifest HD through laboratory investigations, biofluid, and imaging biomarkers are highlighted. Special considerations for juvenile and late-onset HD, along with associated comorbidities like diabetes mellitus, hypertension, and cardiovascular abnormalities, are discussed. The guide emphasizes personalized symptom management, including pharmacotherapy, physical therapy, and nutritional support, while exploring emerging disease-modifying treatments. A multidisciplinary care model is advocated to improve outcomes for HD patients and caregivers in Korea.

Background: and Purpose Previous research on patients with acute ischemic stroke (AIS) has shown a 0.5% incidence of major gastrointestinal bleeding (GIB) requiring blood transfusion during hospitalization. The existing literature has insufficiently explored the long-term incidence in this population despite the decremental impact of GIB on stroke outcomes. Methods: We analyzed the data from a cohort of patients with AIS admitted to 14 hospitals as part of a nationwide multicenter prospective stroke registry between 2011 and 2013. These patients were followed up for up to 6 years. The occurrence of major GIB events, defined as GIB necessitating at least two units of blood transfusion, was tracked using the National Health Insurance Service claims data. Results: Among 10,818 patients with AIS (male, 59%; mean age, 68±13 years), 947 (8.8%) experienced 1,224 episodes of major GIB over a median follow-up duration of 3.1 years. Remarkably, 20% of 947 patients experienced multiple episodes of major GIB. The incidence peaked in the first month after AIS, reaching 19.2 per 100 person-years, and gradually decreased to approximately one-sixth of this rate by the 2nd year with subsequent stabilization. Multivariable analysis identified the following predictors of major GIB: anemia, estimated glomerular filtration rate <60 mL/min/1.73 m2 , and a 3-month modified Rankin Scale score of ≥4. Conclusion Patients with AIS are susceptible to major GIB, particularly in the first month after the onset of AIS, with the risk decreasing thereafter. Implementing preventive strategies may be important, especially for patients with anemia and impaired renal function at stroke onset and those with a disabling stroke.

This review provides a comprehensive framework for the diagnostic approach and management of Huntington’s disease (HD) tailored to the Korean population. Key topics include genetic counseling, predictive testing, and reproductive options like preimplantation genetic testing. Strategies for assessing disease progression in premanifest HD through laboratory investigations, biofluid, and imaging biomarkers are highlighted. Special considerations for juvenile and late-onset HD, along with associated comorbidities like diabetes mellitus, hypertension, and cardiovascular abnormalities, are discussed. The guide emphasizes personalized symptom management, including pharmacotherapy, physical therapy, and nutritional support, while exploring emerging disease-modifying treatments. A multidisciplinary care model is advocated to improve outcomes for HD patients and caregivers in Korea.

Background: and Purpose Previous research on patients with acute ischemic stroke (AIS) has shown a 0.5% incidence of major gastrointestinal bleeding (GIB) requiring blood transfusion during hospitalization. The existing literature has insufficiently explored the long-term incidence in this population despite the decremental impact of GIB on stroke outcomes. Methods: We analyzed the data from a cohort of patients with AIS admitted to 14 hospitals as part of a nationwide multicenter prospective stroke registry between 2011 and 2013. These patients were followed up for up to 6 years. The occurrence of major GIB events, defined as GIB necessitating at least two units of blood transfusion, was tracked using the National Health Insurance Service claims data. Results: Among 10,818 patients with AIS (male, 59%; mean age, 68±13 years), 947 (8.8%) experienced 1,224 episodes of major GIB over a median follow-up duration of 3.1 years. Remarkably, 20% of 947 patients experienced multiple episodes of major GIB. The incidence peaked in the first month after AIS, reaching 19.2 per 100 person-years, and gradually decreased to approximately one-sixth of this rate by the 2nd year with subsequent stabilization. Multivariable analysis identified the following predictors of major GIB: anemia, estimated glomerular filtration rate <60 mL/min/1.73 m2 , and a 3-month modified Rankin Scale score of ≥4. Conclusion Patients with AIS are susceptible to major GIB, particularly in the first month after the onset of AIS, with the risk decreasing thereafter. Implementing preventive strategies may be important, especially for patients with anemia and impaired renal function at stroke onset and those with a disabling stroke.

Background and Objectives: The Valsalva test, although commonly utilized to assess the Eustachian tube function, is limited by drawbacks such as inconsistent pressure increases in the nasal cavity. Thus we introduced the “Popper test,” a tympanic membrane inflation test using the automatic middle ear inflation device known as middle ear inflation device (MEID), to explore its viability as an alternative to the Valsalva test.Subjects and Method We sampled 80 ears from patients between June 1, 2023, and August 1, 2023. Each patient underwent both the Valsalva and Popper tests using the MEID. Participants were divided into three categories: the “unable” group (patients who could not follow the Valsalva maneuver) and the “successful” and “unsuccessful” groups (patients whose attempts at the Valsalva or Popper tests either successed or failed). Success or failure was determined using an otoscope to assess the bulging of the tympanic membrane. Results: Of the 68 ears with normal middle ear pressure, 30.9% (21 ears) showed an inability to perform the Valsalva test, 45.6% (31 ears) successfully inflated the tympanic membrane via the Valsalva test, and 23.5% (16 ears) failed. Conversely, the Popper test resulted in an 88.2% (60 ears) success rate for inflating the tympanic membrane, with only 11.8% (8 ears) failing. Conclusion Variability observed in the Valsalva test outcomes may be attributed to individual differences and the instructor’s technique. MEID, as utilized in the Popper test, offers a promising alternative to the Valsalva test, potentially enhancing the reliability by minimizing individual variation. However, the diagnostic performance may be dependent on the properties of the MEID.

Background: Sanger sequencing is a technology used to identify the gene sequence variants causing rare genetic disorders. However, designing and implementing a proficiency scheme for Sanger sequencing-based genetic testing is challenging because many molecular diagnostic laboratories are running sequencing tests for tens to hundreds of target genes. As such, we aimed to design and implement a method-based proficiency testing (PT) method for Sanger sequencing and to assess its feasibility in Korea. Methods: A pathogenic low density lipoprotein receptor (LDLR) variant was chosen as the positive PT material, and material without an LDLR variant was used as the negative PT material. We distributed the two PT materials with primer pair sets to 17 molecular diagnostic laboratories nationwide.We calculated the correct results (%) for variation type, zygosity, nucleotide change, amino acid change, variant classification, and clinical interpretation. Results: Fourteen laboratories responded to the survey. The results for the two PT materials were 100% correct for all evaluation points including variant type, zygosity, nucleotide change, amino acid change, variant classification, and clinical interpretation. Conclusions This pilot PT survey demonstrates a feasibility of using method-based PT for assessing the Sanger sequencing performance of molecular diagnostic laboratories in Korea.

Purpose: This study aimed to define an optimal age cutoff for early-onset gastric cancer (EOGC) and compare its characteristics with those of late-onset gastric cancer (LOGC) using nationwide survey data. Methods: Using data from a nationwide survey, this comprehensive population-based study analyzed data spanning 3 years (2009, 2014, and 2019). The joinpoint analysis and interrupted time series (ITS) methodology were employed to identify age cutoffs for EOGC based on the sex ratio and tumor histology. Clinicopathologic characteristics and surgical outcomes were compared between the EOGC and LOGC groups. Results: The age cutoff for defining EOGC was suggested to be 50 years, supported by joinpoint and ITS analyses. Early gastric cancer was predominantly present in the EOGC and LOGC groups. Patients with EOGC comprised 20.3% of the total study cohort and demonstrated a more advanced disease stage compared to patients with LOGC. However, patients with EOGC underwent more minimally invasive surgeries, experienced shorter hospital stays, and had lower postoperative morbidity and mortality rates. Conclusion This study proposes an age of ≤50 years as a criterion for defining EOGC and highlights its features compared to LOGC. Further research using this criterion should guide tailored treatment strategies and improve outcomes for young patients with gastric cancer.