Background: Genetic alterations play a pivotal role in multiple myeloma (MM) development and therapeutic resistance. Traditionally, the genetic profiling of MM requires invasive bone marrow (BM) procedures; however, these procedures are associated with patient discomfort and cannot fully capture the spatial and temporal heterogeneity of the disease.Therefore, we investigated the clinical implications of liquid biopsy using targeted deep sequencing. Methods: We analyzed the genetic profiles of circulating tumor DNA (ctDNA) by targeted deep sequencing from 102 patients, including those with monoclonal gammopathy of undetermined significance (MGUS, N = 7), smoldering MM (N = 6), and symptomatic MM (N = 89). Results: The number of ctDNA mutations increased with disease progression from MGUS to MM, with averages of 1.0 mutations in MGUS, 1.8 mutations in smoldering MM, and 1.9 mutations in MM, respectively. Shared mutations between BM and ctDNA were more prevalent in MM (68.9%) than in MGUS (25.0%). RAS/RAF and TP53 mutations were significantly enriched in MM ctDNA. Specific mutations were associated with clinical features in patients with MM: hypercalcemia and TET2 (P = 0.006), renal insufficiency and NRAS (P = 0.012), paramedullary myeloma and TP53(P = 0.02), and extramedullary myeloma and NRAS (P = 0.007). TET2 mutations significantly affected 2-yr progression-free survival (hazard ratio = 7.11, P = 0.003). Serial ctDNA profiling accurately predicted treatment response in patients with MM. Conclusions Our findings highlight the potential of liquid biopsy for understanding MM progression and prognosis utilizing a minimally invasive approach, paving the way for its integration into personalized treatment strategies and real-time disease monitoring.

Enterococcus faecium, particularly in its multidrug-resistant forms, causes invasive nosocomial infections. Given the limited data comparing the effectiveness of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and the CLSI clinical breakpoints (CBPs) for quinupristin–dalfopristin (QD) resistance and the need to evaluate their practical application, we retrospectively investigated the susceptibility patterns of 287 E.faecium bloodstream isolates from Korean hospitals to QD using the updated EUCAST and CLSI CBPs and two antimicrobial susceptibility testing methods: disk diffusion (DD) and Sensititre broth microdilution (Sensititre). QD resistance rates were 5.9% (CLSI) and 18.8% (EUCAST) for DD and 22.6% (CLSI) and 28.2% (EUCAST) for Sensititre. The most prevalent QD resistance gene types among QD-resistant isolates were ermB+msrC+ or ermB– msrC+. Categorical agreement between DD and Sensititre ranged from 77.7% to 90.7%, depending on the testing method and CBPs applied. The EUCAST zone diameter CBPs more effectively help identify QD-resistant E. faecium isolates using the DD method than the CLSI zone diameter CBPs. In comparison, the CLSI minimum inhibitory concentration (MIC) CBPs provide more reliable results for resistance classification in the Sensititre method than EUCAST MIC CBPs. These findings would help improve clinical decision-making for treating multidrug-resistant E. faecium infections.

Background: Genetic neuromuscular diseases (NMDs) are a heterogeneous group of conditions that primarily affect the peripheral nerves, muscles, and neuromuscular junctions. This study was performed to identify pathogenic or likely pathogenic variants (PLPVs), calculate carrier frequencies, and predict the genetic prevalence of autosomal recessive-NMDs (AR-NMDs) in a Korean population. Methods: In total, 267 genes were associated with AR-NMDs. We analyzed genetic variants from 984 Korean whole genomes and identified PLPVs to assess the carrier frequency and genetic prevalence of the variants. Results: We identified 165 PLPVs, including 75 literature verified and 90 manually verified variants. Most PLPVs in AR-NMD genes were frameshifts (61, 37.0%), followed by nonsense (36, 21.8%), missense (35, 21.2%), and splice variants (28, 17.0%). The carrier frequency of the AR-NMDs was 27.1%. DYSF exhibited the highest carrier frequency (1.63%), followed by GAA (1.55%), HEXB (1.53%), PREPL (0.76%), NEB (0.66%), ADSS1 (0.65%), ALPK3 (0.65%), and CHRNG (0.65%). The predicted genetic prevalence of AR-NMDs in the Korean population was 38.0 cases per 100,000 individuals. DYSF (6.7 cases per 100,000 individuals) showed the highest genetic prevalence. The variant with the highest allele frequency was c.1250C>T in HEXB at 0.00764, followed by c.[752T>C; c.761C>T] in GAA at 0.00505, and c.2055+2T>G in DYSF at 0.00437. Conclusion Our study suggests that 27.1% of the Korean population are healthy carriers of at least one AR-NMD causing PLPV, revealing the genetic prevalence of NMDs in the Korean population.

Background: Genetic neuromuscular diseases (NMDs) are a heterogeneous group of conditions that primarily affect the peripheral nerves, muscles, and neuromuscular junctions. This study was performed to identify pathogenic or likely pathogenic variants (PLPVs), calculate carrier frequencies, and predict the genetic prevalence of autosomal recessive-NMDs (AR-NMDs) in a Korean population. Methods: In total, 267 genes were associated with AR-NMDs. We analyzed genetic variants from 984 Korean whole genomes and identified PLPVs to assess the carrier frequency and genetic prevalence of the variants. Results: We identified 165 PLPVs, including 75 literature verified and 90 manually verified variants. Most PLPVs in AR-NMD genes were frameshifts (61, 37.0%), followed by nonsense (36, 21.8%), missense (35, 21.2%), and splice variants (28, 17.0%). The carrier frequency of the AR-NMDs was 27.1%. DYSF exhibited the highest carrier frequency (1.63%), followed by GAA (1.55%), HEXB (1.53%), PREPL (0.76%), NEB (0.66%), ADSS1 (0.65%), ALPK3 (0.65%), and CHRNG (0.65%). The predicted genetic prevalence of AR-NMDs in the Korean population was 38.0 cases per 100,000 individuals. DYSF (6.7 cases per 100,000 individuals) showed the highest genetic prevalence. The variant with the highest allele frequency was c.1250C>T in HEXB at 0.00764, followed by c.[752T>C; c.761C>T] in GAA at 0.00505, and c.2055+2T>G in DYSF at 0.00437. Conclusion Our study suggests that 27.1% of the Korean population are healthy carriers of at least one AR-NMD causing PLPV, revealing the genetic prevalence of NMDs in the Korean population.

Background: and Purpose This study evaluated the diagnostic utility of an anti-signal-recognition particle 54 (anti-SRP54) antibody-based enzyme-linked immunosorbent assay (ELISA) as well as the clinical, serological, and pathological characteristics of patients with SRP immune-mediated necrotizing myopathy (IMNM). Methods: We evaluated 87 patients with idiopathic inflammatory myopathy and 107 healthy participants between January 2002 and December 2023. The sensitivity and specificity of the ELISA for anti-SRP54 antibodies were assessed, and the clinical profiles of patients with antiSRP54 antibodies were determined. Results: The ELISA for anti-SRP54 antibodies had a sensitivity and specificity of 88% and 99%, respectively, along with a test–retest reliability of 0.92 (p<0.001). The 32 patients diagnosed with anti-SRP IMNM using a line-blot immunoassay included 28 (88%) who tested positive for anti-SRP54 antibodies using the ELISA, comprising 12 (43%) males and 16 (57%) females whose median ages at symptom onset and diagnosis were 43.0 years and 43.5 years, respectively. Symptoms included proximal muscle weakness in all 28 (100%) patients, neck weakness in 9 (32%), myalgia in 15 (54%), dysphagia in 5 (18%), dyspnea in 4 (14%), dysarthria in 2 (7%), interstitial lung disease in 2 (7%), and myocarditis in 2 (7%). The median serum creatine kinase (CK) level was 7,261 U/L (interquartile range: 5,086–10,007 U/L), and the median anti-SRP54 antibody level was 2.0 U/mL (interquartile range: 1.0–5.6 U/mL). The serum CK level was significantly higher in patients with coexisting anti-Ro-52 antibodies. Conclusions This study has confirmed the reliability of the ELISA for anti-SRP54 antibodies and provided insights into the clinical, serological, and pathological characteristics of South Korean patients with anti-SRP IMNM.

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.

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.

Purpose: Prostate cancer ranks as the second most common cancer in men globally, representing a significant cause of cancer-related mortality. Metastasis, the spread of cancer cells from the primary site to distant organs, remains a major challenge in managing prostate cancer. Pyruvate dehydrogenase kinase 4 (PDK4) is implicated in the regulation of aerobic glycolysis, emerging as a potential player in various cancers. However, its role in prostate cancer remains unclear. This study aims to analyze PDK4 expression in prostate cancer cells and human samples, and to explore the gene's clinical significance. Materials and Methods: PDK4 expression was detected in cell lines and human tissue samples. Migration ability was analyzed using Matrigel-coated invasion chambers. Human samples were obtained from the Kyungpook National University Chilgok Hospital. Results: PDK4 expression was elevated in prostate cancer cell lines compared to normal prostate cells, with particularly high levels in DU145 and LnCap cell lines. PDK4 knockdown in these cell lines suppressed their invasion ability, indicating a potential role of PDK4 in prostate cancer metastasis. Furthermore, our results revealed alterations in epithelial-mesenchymal transition markers and downstream signaling molecules following PDK4 suppression, suggesting its involvement in the modulation of invasion-related pathways. Furthermore, PDK4 expression was increased in prostate cancer tissues, especially in castration-resistant prostate cancer, compared to normal prostate tissues, with PSA and PDK4 expression showing a significantly positive correlation. Conclusions PDK4 expression in prostate cancer is associated with tumor invasion and castration status. Further validation is needed to demonstrate its effectiveness as a therapeutic target.

Background: The novel sodium-glucose cotransporter-2 (SGLT2) inhibitor enavogliflozin effectively lowers glycosylated hemoglobin levels and body weights without the increased risk of serious adverse events; however, the long-term clinical benefits of enavogliflozin in terms of cardiovascular and renal outcomes have not been investigated. Methods: This study is an investigator-initiated, multicenter, randomized, pragmatic, open-label, active-controlled, non-inferiority trial. Eligible participants are adults (aged ≥19 years) with type 2 diabetes mellitus (T2DM) who have a history of, or are at risk of, cardiovascular disease. A total of 2,862 participants will be randomly assigned to receive either enavogliflozin or other SGLT2 inhibitors with proven cardiorenal benefits, such as dapagliflozin or empagliflozin. The primary endpoint is the time to the first occurrence of a composite of major adverse cardiovascular or renal events (Clinical Research Information Service registration number: KCT0009243). Conclusion This trial will determine whether enavogliflozin is non-inferior to dapagliflozin or empagliflozin in terms of cardiorenal outcomes in patients with T2DM and cardiovascular risk factors. This study will elucidate the role of enavogliflozin in preventing vascular complications in patients with T2DM.