Background: s/Aims: Phase angle (PhA), as measured by bioelectrical impedance analysis, provides insights into hydration and nutritional status, making it a prognostic indicator of frailty. While low preoperative PhA has been linked to postoperative complications in cancer patients, its predictive value in individuals undergoing pancreaticoduodenectomy (PD) has not been thoroughly investigated.This study aims to evaluate the clinical utility of preoperative PhA in predicting postoperative complications for patients undergoing PD. Methods: Among 41 patients who underwent PD at Seoul National University Hospital between September and December 2024, 35 were included in the analysis after excluding 6 patients who had concomitant blood vessel or other organ resections. Patients were divided into low (Comprehensive Complication Index [CCI] ≤ 20) and high (CCI > 20) complication groups based on the CCI, derived from the Clavien–Dindo classification. The differences in PhA between the two groups were analyzed, and logistic regression was performed to assess the relationship between PhA and CCI. Results: The mean PhA was significantly lower in the high-CCI group compared to the low-CCI group (5.7° vs. 6.7°, p = 0.025). Multivariate logistic regression analysis indicated that PhA (odds ratio: 0.17; 95% confidence interval: 0.04–0.68; p = 0.012) was an independent predictor of high CCI. A low preoperative PhA was associated with an increased risk of postoperative complications following PD. Conclusions Preoperative PhA may serve as a valuable predictive indicator of postoperative complications after PD, enabling the identification of patients who could benefit from preoperative prehabilitation, including nutritional support.

Background: Mycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) in children, with a rising incidence of macrolide resistance. Early diagnosis is crucial for reducing the disease burden; however, current diagnostic tools have limitations.We evaluated the diagnostic accuracy of serological assays and their performance based on symptom onset in children with CAP. Methods: From September 2023 to September 2024, we prospectively enrolled children with CAP, classified as M. pneumoniae pneumonia (MPP) or non-MPP, from 16 hospitals in Korea. Serological testing included chemiluminescence immunoassay (CLIA) and ELISA for detecting IgM and IgG, along with particle agglutination (PA) for total antibody measurements. Serological responses were analyzed at different times after symptom onset (0–4, 5–9, and 10–21 days). Results: Among 472 children with CAP (362 MPP, 110 non-MPP), 138 (29.2%) underwent PA testing, and 334 (70.8%) underwent IgM testing. PA at a 1:640 cutoff showed 48.0% sensitivity and 100% specificity. CLIA and ELISA showed comparable sensitivities (69.1% vs. 69.2%) and specificities (76.9% vs. 66.7%) for IgM testing. Seropositivity increased significantly with time since symptom onset (P for trend < 0.001), reaching 97.9% for IgM, 62.5% for IgG, and 94.7% for PA at 10–21 days. Conclusions The time post-symptom onset significantly influenced the diagnostic utility of serological tests for pediatric MPP, which showed limited value during the early stage of illness. These findings emphasize the importance of symptom onset-based interpretation of serological test results and their utility in complementing PCR when optimizing MPP diagnosis in children.

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.

This study aimed to determine the prevalence of human epidermal growth factor receptor 2 (HER2)–ultralow breast cancer among cases initially classified as HER2 immunohistochemistry (IHC) 0 and assess interobserver variability in interpreting low-level HER2 expression. Methods: In this multicenter retrospective study, all invasive breast cancer cases diagnosed between January and December 2022 across 10 Korean institutions were retrieved. Institutional pathologists reexamined HER2 IHC slides originally reported as IHC 0 according to the 2018 American Society of Clinical Oncology/College of American Pathologists guidelines and reclassified them as HER2-null (0), HER2-ultralow (0+), or HER2-low (1+). Slides from 10% of HER2-null and HER2-ultralow cases were digitized for central review and independently assessed by two pathologists, with discrepancies resolved by consensus. Results: Among 8,026 cases, 2,836 cases (35.5%) were initially reported as IHC 0. Upon re-review, 1,673 (59.0%), 1,139 (40.2%), and 24 (0.8%) cases were reclassified as HER2-null, HER2-ultralow, and HER2-low, respectively. The prevalence of HER2-ultralow breast cancer varied considerably across institutions (23.7%–78.1%). Central review of 268 digitized cases showed concordance in 193 cases (72.0%). Among the 75 discordant cases, 54 tumors (72.0%) were upgraded from HER2-null to HER2-ultralow, and 18 (24.0%) tumors were upgraded from HER2-ultralow to HER2-low. Furthermore, two tumors (2.7%) were downgraded from HER2-ultralow to HER2-null. Conclusions: Approximately 40% of cases initially categorized as IHC 0 were reclassified as HER2-ultralow. The substantial inter-institutional variability observed in interpreting low-level HER2 expression highlights the need for standardized training and quality assurance to ensure accurate identification of patients eligible for HER2-targeted antibody–drug conjugates.

Objective: To evaluate the prognostic impact of radiologic and pathologic features in patients with interstitial lung disease (ILD) other than idiopathic pulmonary fibrosis (IPF), and to identify the factors associated with the development of progressive pulmonary fibrosis (PPF) and survival. Materials and Methods: This study retrospectively enrolled 75 patients diagnosed with ILD other than IPF who underwent surgical lung biopsy between January 2004 and December 2020. Three chest radiologists independently reviewed the CT features and extent of fibrosis on preoperative and follow-up CT scans. Two pathologists reviewed the histopathological features, including the presence of interstitial pneumonia. The time to PPF and overall survival were estimated using the Kaplan-Meier method. The associations of CT and pathological features with PPF and all-cause mortality were examined using standard Cox regression and time-dependent Cox models, respectively. Results: A total of 75 non-IPF ILD patients (mean age ± standard deviations 56.4 ± 13.2 years; range, 40–88 years) were enrolled. The median follow-up duration was 75.3 months (range, 7.8–189.8 months). Traction bronchiectasis on CT (adjusted hazard ratio [HR], 6.40; P = 0.003) and body mass index (adjusted HR per 1-kg/m2 increase, 0.82; P = 0.002) were found to be significantly associated with PPF in multivariable analysis. Radiological progression (adjusted HR, 18.44;P < 0.001), symptomatic progression (adjusted HR, 4.19; P = 0.011), and age (adjusted HR for 1-year increase, 1.12; P < 0.001) were significantly associated with death. Conclusion Traction bronchiectasis on CT was a significant predictor of PPF, while radiologic and symptomatic progression and older age were associated with poorer survival in patients with ILD other than IPF. These findings indicate that careful radiological evaluation and symptom monitoring may help to predict disease progression and outcomes in patients with nonIPF ILD.

Objective: This study aimed to evaluate the accuracy of predicting final adult height (FAH) in Korean girls with central precocious puberty (CPP) using artificial intelligence (AI)-derived bone age assessments integrated into the Bayley–Pinneau (BP) or Korean National Growth Chart (KGC) prediction models. Materials and Methods: This single-center, retrospective study included 122 Korean girls with CPP who received gonadotropinreleasing hormone agonist (GnRHa) treatment for at least two years between January 2000 and November 2022. We assessed bone age and predicted adult height at the initiation and completion of GnRHa treatment. We used three bone age assessment methods: human expert assessment based on the Greulich-Pyle (GP) atlas (Human-GP), AI-derived GP (AI-GP), and AI-weighted GP scoring (AI-GPw). We calculated predicted adult heights (PAHs) using both the BP and KGC models, generating 12 PAH estimates per patient (2 time points x 3 bone-age methods x 2 height-prediction models). We assessed prediction accuracy and agreement with FAH using linear regression analysis and Bland–Altman plots and performed multivariable analysis to identify significant predictors of FAH. Results: Human-GP, AI-GP, and AI-GPw demonstrated comparable overall performance in predicting FAH (R 2 : 0.470–0.646 and 0.691–0.822 for treatment initiation and completion, respectively). AI-GPw combined with BP yielded slightly better point estimates but showed no statistically significant differences. At both time points, the BP model demonstrated consistently narrower 95% limits of agreement (LoA) than the KGC model. Multivariable analysis identified AI-GPw-BP and height percentile score as significant predictors of FAH at both time points; mid-parental height was significant only at treatment initiation. Conclusion Human-GP, AI-GP, and AI-GPw demonstrated comparable accuracy in predicting FAH. The BP model demonstrated consistently narrower 95% LoA than did the KGC model. AI-GPw-BP was an independent predictor of FAH. These findings support the clinical utility of AI-derived bone age assessments for individualized FAH prediction in patients with CPP.

BACKGROUND/OBJECTIVES: Dietary supplement use is common among breast cancer survivors, but studies on Asian populations remain limited. This study investigated dietary supplement use among Korean breast cancer survivors, distinguishing between vitamin/ mineral (VM) and non-vitaminon-mineral (NVNM) supplements. SUBJECTS/METHODS: This cross-sectional study included 1,136 stage I–III breast cancer survivors from 12 Korean hospitals, who survived more than 6 mon post-surgery. The participants completed a questionnaire on post-diagnostic dietary supplement use. Stepwise logistic regression was applied, calculating odds ratios (ORs) and 95% confidence intervals (CIs) to identify the demographic and clinical factors associated with VM and NVNM use. RESULTS: Seventy percent of survivors reported supplement use, with 25% using a single product. The most common VM supplements were multivitamins/minerals, vitamin D, and vitamin C, while the most common NVNM supplements included omega-3 fatty acids, probiotics, and ginseng. Survivors with higher education and greater physical activity were more likely to use VM supplements (ORs [95% CIs], 2.74 [1.76–4.25] for college graduates or above vs. middle school or below; 1.38 [1.02–1.88] for the most active group vs. the least active group). NVNM use was associated with higher education, greater physical activity levels, and a history of smoking (ORs [95% CIs], 2.29 [1.46–3.58] for college graduates or above vs. middle school or below; 1.52 [1.13–2.06] for the most active group vs. the least active group; 2.00 [1.23–3.25] for ever smokers vs. never smokers). Survivors who had undergone chemotherapy were also more likely to use NVNM supplements than those who had not (OR [95% CI], 1.37 [1.02–1.84]). CONCLUSION Seventy percent of Korean breast cancer survivors used dietary supplements in this study. VM use was associated with higher education and physical activity, while higher NVNM use was associated with higher education, greater physical activity, a history of smoking, and chemotherapy.

Purpose: Although host body composition, nutritional and systemic inflammatory status have been suggested to have an impact on prognosis in patients with colorectal cancer (CRC), their impact on patients with stage IV CRC remains unclear.This study investigated the prognostic effects of those parameters in patients initially diagnosed with stage IV CRC who underwent surgery. Methods: Patients with stage IV CRC who underwent surgery were selected. Preoperative computed tomography images were evaluated for skeletal muscle index, skeletal muscle density (SMD), visceral fat area (VFA), and subcutaneous fat area (SFA). For nutritional status and systemic inflammation, prognostic nutritional index (PNI), neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) were used. The Cox proportional hazard model was used to evaluate the prognostic significance of progression-free survival (PFS) after adjustment for the other covariates in the model. Results: Data of 134 patients with stage IV CRC who underwent surgery between January 2005 and February 2014 were included. SMD, VFA, SFA, PNI, NLR, LMR, and PLR were associated with PFS in the univariable analysis. In the multivariable analysis, SFA (hazard ratio [HR], 0.612; 95% confidence interval [CI], 0.389–0.961; P = 0.033), and PNI (HR, 0.536; 95% CI, 0.345–0.832; P = 0.005) were identified to be independent prognostic factors for PFS. Conclusion SFA and PNI both demonstrated prognostic significance in patients with stage IV CRC. Accordingly, we believe further studies are warranted to determine whether incorporating these factors can aid in surgical decision-making for stage IV CRC patients.

Purpose: Colorectal cancer (CRC) remains a leading cause of cancer-related mortality, necessitating the identification of novel therapeutic targets. The E3 ubiquitin ligase WW domain-containing E3 ubiquitin protein ligase 2 (WWP2) has been implicated in various cancers, yet its specific role and underlying molecular mechanisms in CRC are poorly understood. This study aimed to investigate the functional role of WWP2 in CRC progression and to elucidate its regulatory mechanisms. Methods: WWP2 expression was evaluated in CRC patient tissues and cell lines using immunohistochemistry, quantitative real-time polymerase chain reaction, and western blotting. The biological functions of WWP2 were assessed using in vitro assays for cell proliferation, migration, and invasion following adenovirus-mediated overexpression. The molecular mechanism was investigated by analyzing the protein expression levels of p53 and its downstream target, p21, via western blot. An in vivo xenograft mouse model was used to confirm the oncogenic role of WWP2. Results: WWP2 expression was significantly upregulated in CRC tissues. Overexpression of WWP2 promoted CRC cell proliferation, migration, and invasion. Mechanistically, increased WWP2 expression led to a marked reduction in the protein levels of the tumor suppressor p53. Consequently, the expression of the p53 downstream target, the cell cycle inhibitor p21, was also suppressed. In the xenograft model, WWP2 overexpression significantly enhanced tumor growth. Conclusion Our findings demonstrate that WWP2 functions as an oncogene in CRC. It promotes cancer progression by destabilizing the tumor suppressor p53 and downregulating p21. This study highlights the WWP2-p53-p21 axis as a potential novel therapeutic target for CRC.

Soft tissue sarcomas (STSs), a diverse group of mesenchymal malignancies, are characterized primarily by copy-number alterations rather than a high tumor mutation burden. In this study, we sought to identify expression-based biomarkers in complex karyotype STS (CKS) with CDK4-amplification to support improved therapeutic strategies. Using transcriptome data from National Cancer Center (NCC)-CKS samples, we selected genes whose expression levels were more than two-fold higher or less than half in tumor tissues compared with normal tissues. These genes were further filtered by CDK4-amplification status, resulting in 30 candidates, which were refined to 14 differentially expressed genes (DEGs) based on false discovery rate (FDR) significance. Bioinformatics analyses revealed enriched pathways and gene–gene networks related to redox regulation and growth-factor–driven signal transduction, indicating metabolic alterations that may promote tumor survival in CDK4-amplified CKS. A subset of the 14 genes demonstrated prognostic significance in CDK4-amplified patients from the TCGA cohort. Additionally, immune cell marker analysis showed associations between CDK4-amplification and innate immune cell signatures. Together, our findings identify promising therapeutic and prognostic targets linked to CDK4-amplification in CKS. These biomarkers warrant further investigation and may ultimately contribute to improved clinical outcomes for patients with CKS.