Background/Aims: Hepatocellular carcinoma (HCC) exhibits high de novo recurrence rates post-resection. Current post-surgery recurrence prediction methods are limited, emphasizing the need for reliable biomarkers to assess recurrence risk. We aimed to develop methylation-based markers for classifying HCC patients and predicting their risk of de novo recurrence post-surgery. Methods: In this retrospective cohort study, we analyzed data from HCC patients who underwent surgical resection in Korea, excluding those with recurrence within one year post-surgery. Using the Infinium Methylation EPIC array on 140 samples in the discovery cohort, we classified patients into low- and high-risk groups based on methylation profiles. Distinctive markers were identified through random forest analysis. These markers were validated in the cancer genome atlas (n=217), Validation cohort 1 (n=63) and experimental Validation using a methylation-sensitive high-resolution melting (MS-HRM) assay in Validation cohort 1 and Validation cohort 2 (n=63). Results: The low-risk recurrence group (methylation group 1; MG1) showed a methylation average of 0.73 (95% confidence interval [CI] 0.69–0.77) with a 23.5% recurrence rate, while the high-risk group (MG2) had an average of 0.17 (95% CI 0.14–0.20) with a 44.1% recurrence rate (P<0.03). Validation confirmed the applicability of methylation markers across diverse populations, showing high accuracy in predicting the probability of HCC recurrence risk (area under the curve 96.8%). The MS-HRM assay confirmed its effectiveness in predicting de novo recurrence with 95.5% sensitivity, 89.7% specificity, and 92.2% accuracy. Conclusions Methylation markers effectively classified HCC patients by de novo recurrence risk, enhancing prediction accuracy and potentially offering personalized management strategies.

Background: Decreased acetabular version and posterior acetabular coverage of the femoral head have been regarded as the leading causes of sport-related posterior hip dislocation or subluxation. This study aimed to examine the posterior acetabular coverage of the femoral head in 21 patients who sustained posterior hip dislocation or subluxation during sport activities. Methods: The anterior and posterior acetabular rims on 3-dimensional computed tomography (3D-CT) images were delineated on the normal side in these patients. Radiologic signs, including crossover and posterior wall signs, were examined. The fracture center level (FCL) of the posterior acetabular wall was identified on axial CT images of the injured hip and the level was marked on the normal side. The difference in the femoral head coverage by posterior and anterior acetabular rims was measured by measuring the horizontal distance between anterior and posterior acetabular rims at the FCL (posterior-anterior [P-A] index). The acetabular version was measured at the femoral head and FCL using axial CT images of the normal side. Femoral head coverage by the posterior acetabular wall on the normal side was measured using 3D-CT (areal coverage). Results: The crossover and posterior wall signs were positive in 14 and 10 patients, respectively, in 3D-CT images. The FCL was evenly distributed in the proximal half of the posterior acetabular wall. Seven patients had a P-A index of ≤ 0, and all were positive for the crossover sign. The anterior acetabular rim was relatively prominent in these patients. The acetabular version was lower at the FCL than at the femoral head center (p < 0.001). The proximal half areal coverage of the posterior acetabular wall was significantly smaller than the whole areal coverage (p = 0.003). Conclusions Superior–posterior coverage of the femoral head by the posterior acetabular wall was insufficient in patients who sustained hip posterior dislocation or subluxation during sports activities.

Background/Aims: The study investigated the incidence, risk factors, and clinical outcomes of chronic antibiotic-refractory pouchitis (CARP) in Korean patients with ulcerative colitis (UC). Methods: This single-center retrospective study included patients with UC who underwent total proctocolectomy with ileal pouch-anal anastomosis at the Asan Medical Center in Korea between January 1987 and December 2022. The primary outcomes were endoscopic remission and pouch failure. The Cox’s proportional hazard model was used to identify the risk factors for CARP. Results: The clinical data of 232 patients were analyzed. The most common cause of surgery was steroid refractoriness (50.9%), followed by dysplasia/colorectal cancer (26.7%). Among 74 patients (31.9%) with chronic pouchitis (CP), 31 (13.4%) had CARP, and 43 (18.5%) had chronic antibiotic-dependent pouchitis (CADP). The most frequent endoscopic phenotype was focal inflammation of the pouch (CP, 47.3%; CARP, 35.5%; CADP, 55.8%). Patients with CARP were less likely to use concomitant probiotics than patients with CADP (29.0% vs 72.1%, p<0.01). The endoscopic remission rate of CP, CARP, and CADP was 14.9%, 9.7%, and 18.6%, respectively.The pouch failure rate associated with CP, CARP, and CADP was 13.5%, 16.1%, and 11.6%, respectively. Current smoking status (adjusted hazard ratio [aHR], 2.96; 95% confidence interval [CI], 1.27 to 6.90; p=0.01) and previous use of biologics/small molecules (aHR, 2.40; 95% CI, 1.05 to 5.53; p=0.04) were significantly associated with CARP development. Conclusions UC patients who were current smokers and previously used biologics/small molecules had a higher risk of developing CARP. Concomitant use of probiotics was less likely to be associated with CARP development.

Purpose: Myocardial strain imaging is a promising tool for evaluating altered cardiac wall mechanics in thickened myocardium. Circumferential transmural strain difference (cTSD) can be readily measured using feature-tracking magnetic resonance imaging (MRI). This study aimed to explore the correlations between cTSD and other markers of disease in apical hypertrophic cardiomyopathy (ApHCM). Materials and Methods: A retrospective, single-center, case-control study was conducted on patients with ApHCM who underwent 1.5-T or 3.0-T cardiac MRI. Left ventricular (LV) longitudinal and circumferential strains were analyzed using feature-tracking software. cTSD was calculated as the difference between epicardial and endocardial circumferential strains. Global and segmental strains were compared between groups, and correlations between cTSD and LV mass or late gadolinium enhancement (LGE) were analyzed. Results: A total of 29 participants (17 patients with ApHCM, median age 64 years, 71% men; 12 normal controls, median age 55 years, 67% men) were evaluated. Global and segmental cTSD were significantly higher in the ApHCM group than in the normal group from the base to the apex, with the greatest differences at the apex (base 19.6% vs.16.1%, mid 24.5% vs. 16.9%, and apex 36.8% vs. 21.6%, all p < 0.05). Global cTSD showed a moderate positive correlation with indexed LV mass (ρ = 0.599, p = 0.001), while segmental cTSD showed a weak positive correlation with LGE in patients with ApHCM (ρ = 0.239, p < 0.001). Conclusion Segmental cTSD was significantly higher in the ApHCM group than in the normal group, with the greatest difference at the apical segments. This difference was not observed in the full-thickness myocardial circumferential strain. These findings suggest that cTSD may serve as a sensitive imaging biomarker for ApHCM, not only in hypertrophied apex segments but also in non-hypertrophied myocardium.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Background: Postoperative pain management is challenging in patients with oral cancer, especially those undergoing reconstructive surgery. Patient-controlled analgesia (PCA) is widely used, and fentanyl (FTN) concentration adjustments may improve pain control. This study aimed to evaluate the effects of FTN PCA concentration and reconstructive surgery on postoperative pain in patients with oral cancer. Methods: This retrospective observational study analyzed 140 patients with oral cancer who underwent surgery under general anesthesia. Patients were categorized based on FTN PCA dosage (FTN 700 mcg and ketorolac 150 mg vs. FTN 1400 mcg and ketorolac 150 mg). Pain was assessed using the visual analog scale (VAS) at multiple time points postoperatively (0, 12, 24, 36, 48, 60, and 72 h). PCA usage patterns, including demand count, delivery count, and delivery/demand ratios, were compared across subgroups. Missing data were imputed using linear interpolation. Results: PCA usage and pain control were evaluated between the FTN 700 mcg (N = 40) and 1400 mcg (N = 100) groups, stratified by reconstruction status. Demographic characteristics showed no significant difference.In the reconstructive surgery subgroup, patients in the FTN 1400 mcg group showed lower PCA refill counts (1.45 ± 0.69 vs. 1.61 ± 0.58) and fewer delivery counts (17.1 ± 21.3 vs. 25.1 ± 28.5) compared to those in the FTN 700 mcg group, achieving similar or superior pain control with fewer interventions. Similarly, patients without reconstructive surgery in the FTN 1400 mcg group demonstrated lower PCA refill counts, shorter PCA usage times, and fewer delivery counts. VAS scores decreased consistently over time across all groups but remained higher in the reconstruction groups. Logistic regression analysis revealed that patients with reconstructive surgery in the FTN 1400 mcg group were more likely to achieve a VAS score of ≤ 3.0 at 72 h postoperatively (P = 0.022). These findings indicate FTN 1400 mcg’s superiority in managing postoperative pain. Conclusion Comparing FTN PCA dosages, 1400 mcg demonstrated superior pain control to 700 mcg in patients undergoing oral cancer surgery, particularly those who underwent reconstructive surgery. This finding underscores the importance of optimizing FTN dosages to enhance postoperative pain management, reduce PCA-related demands, and achieve better patient outcomes.

Purpose: This study aimed to evaluate the outcomes and current status of reduced-port laparoscopic distal gastrectomy (RLDG) compared with multiport laparoscopic distal gastrectomy (MLDG) based on a 2019 nationwide survey of surgical gastric cancer treatments by the Korean Gastric Cancer Association (KGCA). Materials and Methods: The study was conducted retrospectively from March to December 2020 using data from the 2019 KGCA nationwide survey database. To compare RLDG and MLDG based on age, sex, body mass index, American Society of Anesthesiologists score, histological type, tumor invasion, and lymph node metastasis, propensity score matching was performed. Results: Of the 14,076 registered patients with gastric cancer, the five-port approach was the most favored for multiport gastrectomy, accounting for 6,396 (70.9%) cases, followed by the four-port approach, with 1,462 (16.2%) cases. The single-port approach was used in 303 (3.4%) cases, the two-port approach in 95 (1.1%) cases, and the three-port approach in 731 (8.1%) cases. RLDG was performed in 805 patients (6.4%), MLDG was conducted in 4,831 patients (34.3%), and 804 patients were 1:1 matched in each group. The average operation time was shorter in the RLDG (168.2±49.1 min vs. 179.5±61.5 min, P<0.001). No significant difference was found in blood loss (84.8±115.9 cc vs. 75.5±119.6 cc, P=0.152), overall complication rates (11.3% vs. 13.1%, P=0.254), or complications ≥ to grade IIIa (3.2% vs. 4.4%, P=0.240). Conclusions This study revealed that RLDG is a safe and effective surgical option for gastric cancer with the potential to offer shorter operation times without increasing the risk of complications.

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.

Purpose: This qualitative study explored nurses' experiences in selecting hospitals within a dual labor market framework. Methods: Focus group interviews were conducted with 18 general nurses, divided into three groups of six, each representing both large and medium-sized hospitals. Results: The analysis revealed two themes, four categories, and nine subcategories, highlighting differences between large and medium-sized hospitals. Nurses who choose large hospitals prioritized "professional development" but faced "struggles to maintain professional identity" while those selecting medium-sized hospitals sought "stability and accessibility" but experienced "crisis of professional identity." Conclusion This study highlights significant differences in the factors influencing nurses' hospital choices based on hospital size. These findings provide foundational data for establishing the Enforcement Decree and Rules of the Nursing Act, emphasizing the importance of developing legal measures to strengthen nurses' professional identity and promote a balanced and sustainable nursing labor market.