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: Trapeziectomy with suspension arthroplasty is a reliable treatment for thumb carpometacarpal (CMC) osteoarthritis.We modified the suture suspension technique to add further support to maintain the arthroplasty space by interposition of the dermal allograft. Our aim was to investigate the surgical outcomes of our technique of suspension arthroplasty with dermal allograft interposition (SADI) compared with those of traditional ligament reconstruction with tendon interposition (LRTI) using a half-sling of the flexor carpi radialis (FCR) tendon. Methods: This retrospective study enrolled 26 patients (29 thumbs) with thumb CMC arthritis who underwent trapeziectomy with traditional LRTI using the FCR tendon (15 thumbs; LRTI group) or SADI (14 thumbs; SADI group) between January 2017 and May 2022. Patient-reported outcomes (visual analog scale; the Disabilities of the Arm, Shoulder and Hand score; and patient-rated wrist evaluation), grip strength, and scaphometacarpal distance were measured at baseline and 3 and 12 months postoperatively. The operation time was checked by reviewing medical records. All measurements were compared between the 2 groups. Results: Between baseline and 12-month postoperative follow-up, all patient-reported outcomes significantly improved in both groups. Patient-reported outcomes, grip strength, and scaphometacarpal distance showed no differences between the 2 groups at all follow-up assessments, except for the scaphometacarpal distance being significantly greater in the SADI group at 3 months postoperatively. The operation time was significantly shorter in the SADI group. No complication was observed in either group. Conclusions Our modified suture suspension arthroplasty technique using dermal allograft interposition results in markedly shorter surgical times with similar surgical outcomes compared with those of traditional LRTI using the FCR tendon. This procedure appears to be an effective alternative treatment for thumb CMC arthritis.

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 evaluated the postoperative quality of life (QoL) after various types of gastrectomy for gastric cancer. Materials and Methods: A multicenter prospective observational study was conducted in Korea using the Korean Quality of Life in Stomach Cancer Patients Study (KOQUSS)-40, a new QoL assessment tool focusing on postgastrectomy syndrome. Overall, 496 patients with gastric cancer were enrolled, and QoL was assessed at 5 time points: preoperatively and at 1, 3, 6, and 12 months after surgery. Results: Distal gastrectomy (DG) and pylorus-preserving gastrectomy (PPG) showed significantly better outcomes than total gastrectomy (TG) and proximal gastrectomy (PG) with regard to total score, indigestion, and dysphagia. DG, PPG, and TG also showed significantly better outcomes than PG in terms of dumping syndrome and worry about cancer. Postoperative QoL did not differ significantly according to anastomosis type in DG, except for Billroth I anastomosis, which achieved better bowel habit change scores than the others. No domains differed significantly when comparing double tract reconstruction and esophagogastrostomy after PG. The total QoL score correlated significantly with postoperative body weight loss (more than 10%) and extent of resection (P<0.05 for both).Reflux as assessed by KOQUSS-40 did not correlate significantly with reflux observed on gastroscopy 1 year postoperatively (P=0.064). Conclusions Our prospective observation using KOQUSS-40 revealed that DG and PPG lead to better QoL than TG and PG. Further study is needed to compare postoperative QoL according to anastomosis type in DG and PG.

The fundamental principles for treating ankle fractures, as with other intra-articular fractures, are anatomical reduction and stable internal fixation. Despite successful reduction, between 14% and 40% of patients continue to experience persistent pain or unsatisfactory functional outcomes. Furthermore, approximately 1% of patients progress to post-traumatic arthritis, necessitating further surgical intervention. Ankle fractures are frequently accompanied by intra-articular injuries, including osteochondral lesions, ligament tears, and syndesmosis injuries. Arthroscopy is becoming increasingly prevalent in managing acute ankle fractures by assessing intra-articular damage and facilitating accurate reduction. This review examined the role and indications for arthroscopy in ankle fractures, particularly emphasizing its benefits in diagnosing and managing associated injuries, including osteochondral lesions, syndesmosis, and deltoid ligament injuries. Furthermore, arthroscopy facilitates fracture reduction, offering a minimally invasive approach with a shorter recovery period and enhanced visualization. Its use extends to pediatric fractures and complex cases such as Maisonneuve and calcaneal fractures, potentially improving outcomes while minimizing complications. Understanding the evolving indications and benefits of arthroscopy for ankle fractures can lead to improved clinical outcomes and reduced complications.

Background: Barriers to treatment with intravenous thrombolysis (IVT) for patients with acute ischemic stroke (AIS) in South Korea remain incompletely characterized. We analyze a nationwide prospective cohort to determine patient-level features associated with delayed presentation and non-treatment of potential IVT-eligible patients. Methods: We identified consecutive patients with AIS from 01/2011 to 08/2023 from a multicenter and prospective acute stroke registry in Korea. Patients were defined as IVT candidates if they presented within 4.5 hours from the last known well, had no lab evidence of coagulopathy, and had National Institute of Health Stroke Scale (NIHSS) ≥ 4. Multivariable generalized linear mixed regression models were used to investigate the associations between their characteristics and the IVT candidates or the use of IVT among the candidates. Results: Among 84,103 AIS patients, 41.0% were female, with a mean age of 69 ± 13 years and presentation NIHSS of 4 [interquartile range, 1–8]. Out of these patients, 13,757 (16.4%) were eligible for IVT, of whom 8,179 (59.5%) received IVT. Female sex (adjusted risk ratio [RR], 0.90; 95% confidence interval [CI], 0.86–0.94) and lower years of education (adjusted RR, 0.90; 95% CI, 0.84–0.97 for 0–3 years, compared to ≥ 13 years) were associated with a decreased likelihood of presenting as eligible for IVT after AIS; meanwhile, young age (adjusted RR, 1.12; 95% CI, 1.01–1.24 for ≤ 44 years, compared to 75–84 years) was associated with an increased likelihood of being an IVT candidate. Among those who were eligible for IVT, only age was significantly associated with the use of IVT (adjusted RR, 1.09; 95% CI, 1.03–1.16 for age 65–74 and adjusted RR, 0.83; 95% CI, 0.76–0.90 for ≥ 85 years, respectively). Conclusion Most patients with AIS present outside IVT eligibility in South Korea, and only 60% of eligible patients were ultimately treated. We identified increased age, female sex and lower education as key features on which to focus interventions for improving IVT utilization.

Background: Factors influencing the decline in forced expiratory volume in one second (FEV1 )/forced vital capacity (FVC) for chronic obstructive pulmonary disease (COPD) progression remain uncertain. We aimed to identify risk factors associated with rapid FEV1 / FVC decline in patients with COPD. Methods: This multi-center observational study was conducted from January 2012 to December 2022. Eligible patients were monitored with symptoms, spirometric tests, and treatment patterns over 3 years. Rapid FEV1 /FVC decliners were defined as the quartile of patients exhibiting the highest annualized percentage decline in FEV1 /FVC. Results: Among 1,725 patients, 435 exhibited rapid FEV1 /FVC decline, with an annual change of −2.5%p (interquartile range, −3.5 to −2.0). Rapid FEV1 /FVC decliners exhibited lower body mass index (BMI), higher smoking rates, elevated post-bronchodilator (BD) FEV1 , higher post-BD FEV1 / FVC, and a lower prevalence of Staging of Airflow Obstruction by Ratio (STAR) stage IV. Rapid FEV1 /FVC decline was not linked to the annual exacerbation rate, but there was an association with symptom deterioration and FEV1 decline. In multivariable analyses, low BMI, current smoking, increased modified Medical Research Council dyspnoea score, low post-BD FEV1 , low STAR stage, high forced mid-expiratory flow (FEF 25-75% ), accelerated FEV1 decline, and not initiating dual BD therapy were identified as independent risk factors for rapid FEV1 /FVC decline. Conclusion We identified the risk factors for rapid FEV1 /FVC decline, including BMI, smoking, symptoms deterioration, FEV1 decline, and adherence to standard inhaler treatment. Our findings underscore the potential benefits of maintaining consistent use of long-acting beta-agonist/long-acting muscarinic antagonist even in the presence of worsening symptoms, in attenuating FEV1 /FVC decline.

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.

Purpose: This study aimed to present a novel method for estimating the effective atomic number(Zeff ) using dual-energy computed tomography (DECT) designed to improve accuracy andstreamline clinical workflows by reducing computational complexity. Methods: The proposed model leverages the DECT-derived mass attenuation coefficients without detailed compositional analysis. By incorporating additional parameters into the conventional Rutherford model, such as exponential and trigonometric functions, the model effectively capturescomplex variations in attenuation, enabling precise Zeff estimation. Model fitting was performedusing dual-energy data and evaluated using the percentage difference in error rates. Results: Compared with the Rutherford model, which recorded a maximum error rate of 0.55%, the proposed model demonstrated a significantly lower maximum error rate of 0.15%, highlightingits precision. Zeff estimates for various materials closely matched the reference values, confirmingthe improved accuracy of the model. Conclusions The proposed DECT-based model provides a practical and efficient approach to Zeff estimation, with potential applications in radiation oncology, particularly for accurate stopping power ratio calculations in proton and heavy ion therapies.

Background: Respiratory infections play a major role in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). This study assessed the prevalence of bacterial and viral pathogens and their clinical impact on patients with AECOPD. Methods: This retrospective study included 1,186 patients diagnosed with AECOPD at 28 hospitals in South Korea between 2015 and 2018. We evaluated the identification rates of pathogens, basic patient characteristics, clinical features, and the factors associated with infections by potentially drug-resistant (PDR) pathogens using various microbiological tests. Results: Bacteria, viruses, and both were detected in 262 (22.1%), 265 (22.5%), and 129 (10.9%) of patients, respectively. The most common pathogens included Pseudomonas aeruginosa (17.8%), Mycoplasma pneumoniae (11.2%), Streptococcus pneumoniae (9.0%), influenza A virus (19.0%), rhinovirus (15.8%), and respiratory syncytial virus (6.4%). Notably, a history of pulmonary tuberculosis (odds ratio [OR], 1.66; p=0.046), bronchiectasis (OR, 1.99; p=0.032), and the use of a triple inhaler regimen within the past 6 months (OR, 2.04; p=0.005) were identified as significant factors associated with infection by PDR pathogens. Moreover, patients infected with PDR pathogens exhibited extended hospital stays (15.9 days vs. 12.4 days, p=0.018) and higher intensive care unit admission rates (15.9% vs. 9.5%, p=0.030). Conclusion This study demonstrates that a variety of pathogens are involved in episodes of AECOPD. Nevertheless, additional research is required to confirm their role in the onset and progression of AECOPD.