Purpose: The aim of this study is to compare the detection ability of quality of life (QoL) changes and responsiveness of the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS)-40 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ). Materials and Methods: A multicenter prospective observational study was conducted to evaluate QoL changes after various gastrectomies between January 2021 and April 2022. Participants were instructed to complete the KOQUSS-40 and EORTC QLQ-C30/STO22 preoperatively and at 1, 3, 6, and 12 months postoperatively. QoL changes over time and QoL responsiveness were assessed for each questionnaire. Results: Data from 491 patients who underwent curative gastrectomy for gastric cancer at 22 institutions were analyzed. The summary scores of the KOQUSS-40 and EORTC QLQ-STO22 showed significant differences between the total and proximal gastrectomy groups (p=0.044 and p=0.038, respectively), but no difference was observed for the EORTC QLQ-C30. Dysphagia on the KOQUSS-40 was significantly different between the total and proximal gastrectomy groups (p=0.031); however, dysphagia on the EORTC QLQ-STO22 did not differ. The responsiveness of the KOQUSS-40 was similar to that of the EORTC QLQ in patients who experienced ≥ 10% body weight loss, but approximately 10% less in patients receiving adjuvant chemotherapy than the EORTC QLQ. Conclusion KOQUSS-40 has several advantages over EORTC QLQ-C30/STO22 when comparing QoL between the total and proximal gastrectomy groups. The findings provide information for researchers investigating the QoL of patients who have undergone curative gastrectomy for gastric cancer.

Purpose: The male predominance in the incidence of gastric cancer (GC) is established; however, sex differences in the prognosis of GC remain controversial. As such, this study analyzed the prognosis of patients with GC based on age and sex. Materials and Methods: Data from 14,739 patients diagnosed with GC at Seoul National University Bundang Hospital between 2003 and 2023 were analyzed. Baseline characteristics, histological types of GC, overall and GC-specific survival rates (age and stage stratification), and associated risk factors were analyzed. Results: Females were significantly younger (p < 0.001) and exhibited more gastric body cancers (p < 0.001) and tumors with diffuse-type or poorly differentiated histology (p < 0.001) than males. Females exhibited an advantage over males in terms of overall survival (p=0.004), but not in GC-specific survival. However, age stratification revealed significant sex differences, that females < 50 years of age exhibited survival disadvantages (p < 0.001); however, this trend was reversed with age, and females > 60 years exhibited survival advantages (p < 0.001) for both overall and GC-specific survival. This may be explained by the lower ratio of diffuse-type GC as females age. Furthermore, in the analysis according to stage, females with stage IV disease exhibited significant survival disadvantages, with significantly younger age and a higher proportion of diffuse-type GC which exhibits aggressive features, resulting in poorer survival than in males. Conclusion Age and stage stratification revealed significant differences in survival between the sexes, which can be helpful for public health strategies.

Purpose: This retrospective study evaluated the efficacy and safety of a weekly carfilzomib, cyclophosphamide, and dexamethasone (KCd) regimen in patients with relapsed or refractory multiple myeloma (RRMM) who had been previously treated with both bortezomib- and lenalidomide-containing regimens. Materials and Methods: We conducted a retrospective analysis of 33 patients with RRMM who received the KCd regimen between March 2020 and February 2024. All patients had prior exposure to both bortezomib and lenalidomide, and the majority (93.9%) were refractory to lenalidomide. Carfilzomib was administered once weekly at 70 mg/m2 (after a step-up dose), along with oral cyclophosphamide and dexamethasone. Treatment response was assessed according to the International Myeloma Working Group criteria, and survival outcomes were analyzed. Results: The overall response rate was 66.7%, including a complete response or better in 15.1% of patients and a very good partial response or better in 42.4%. With a median follow-up of 31.7 months, the median progression-free survival was 13.5 months (95% confidence interval, 11.47 to 15.53), while the median overall survival was not reached. The most common grade ≥ 3 adverse event was neutropenia (15.2%). Non-hematologic grade ≥ 3 toxicities were infrequent and manageable. Conclusion The weekly KCd regimen demonstrated encouraging efficacy and tolerability in a heavily pretreated RRMM population. These findings support its use as a feasible treatment option, particularly in patients refractory to lenalidomide.

Purpose: This study compared healthy lifestyle (HLS) practices and awareness regarding the use of chatbots (A-uC) for health management between childhood and adolescent cancer survivors (CACSs) and their parents, with the aim of assessing the feasibility of tailored artificial intelligence (AI) chatbot-based interventions for holistic survivorship care. Methods: A descriptive comparative design was employed involving 80 CACSs and 80 parents (N=160) recruited through the Korean Pediatric Cancer Foundation. HLS practices were assessed using a validated seven-domain instrument encompassing physical activity, nutrition, interpersonal relations, stress management, positive life perspective, health responsibility, and spiritual health. A-uC was evaluated using an extended technology acceptance model-based tool. Responses to the open-ended question addressing unmet HLS practices were analyzed using latent Dirichlet allocation topic modeling. Results: No significant differences were observed between CACSs and parents in overall HLS (CACSs: 3.16±0.80; parents: 3.18±0.36, p=.74). While perceptions across most A-uC domains did not differ significantly, parents demonstrated a significantly higher “intention to use” chatbots for health management than CACSs (p=.03). The mean A-uC scores exceeded 4 (out of 5) in both groups, reflecting positive perceptions of chatbot-based HLS support. Topic modeling identified “exercise,” “healthy diet,” and “regular lifestyle” as common unmet areas. Conclusion CACSs and their parents share largely concordant views on HLS and A-uC, with a strong interest in chatbot interventions. These findings underscore the potential of tailored AI chatbot programs to address unmet lifestyle needs and promote holistic survivorship care.

Limited data exist regarding the real-world practices and clinical outcomes in patients with ischemic heart failure with reduced left ventricular ejection fractions (LVEFs).Using nationwide registry data from South Korea, we aimed to investigate long-term outcomes and clinical practices, especially implantable cardioverter defibrillators (ICDs) implantation, in patients with reduced LVEFs at least 40 days after acute myocardial infarction (AMI). Of 13,056 patients with AMI between 2011 and 2015, we analyzed 350 (median age, 66 years [interquartile range, 56-75]) who had LVEFs <40% on follow-up transthoracic echocardiogram 40 days after the index event. The primary outcome was cardiac-cause mortality at 3 years. Secondary outcomes comprised major cardiovascular events as well as outcomes defined by the use of ICDs, cardiac resynchronization therapy defibrillators (CRT-Ds), and electrophysiology studies. Among 350 patients, 39 (11.1%) died from cardiac causes during 3 years of follow-up. Eleven (3.1%) were hospitalized for ventricular tachycardia. The rate of ICD or CRT-D implantation up to 3 years was 5.7% (20/350). Cox time-to-event analysis revealed older age, LVEF <30%, diabetes mellitus, and previous MI or revascularization as positively associated with cardiac death, whereas the use of statins and body weight <67 kg were negatively associated. This nationwide Korean registry demonstrated that only 5.7% of patients who had reduced LVEFs after 40 days of AMI underwent ICD implantations over 3 years. Considering the high mortality, concerted efforts are needed to improve clinical outcomes for patients who may have been candidates for ICD implantation.

Pharmacogenomic variations may significantly influence responses to commonly prescribed stroke medications. Despite accumulating evidence, genetic testing has not yet been widely integrated into stroke care. This review summarizes current evidence and provides practical guidance for clinical implementation. Pharmacogenomic studies and clinical guidelines related to antiplatelet agents, anticoagulants, and statins were reviewed, with particular emphasis on East Asian populations. Substantial evidence supports genotype-guided use of clopidogrel (CYP2C19), warfarin (CYP2C9, VKORC1, CYP4F2), and statins (SLCO1B1, ABCG2). For aspirin, PTGS1/2 and PEAR1 variants have been investigated; however, current data remain insufficient for clinical application. Regarding direct oral anticoagulants (DOACs), candidate genes such as ABCB1 and CES1 demonstrate pharmacokinetic associations, though robust clinical outcome data are lacking. Distinct allele frequencies in East Asians—such as higher prevalence of CYP2C19 and ABCG2 variants—underscore the need for population-specific strategies. Beyond single-gene approaches, polygenic risk scores, pharmacogenomic panels, and integration with multi-omics data and artificial intelligence represent promising directions for personalized therapy. Pharmacogenomic testing can enhance stroke pharmacotherapy, particularly in populations with high frequencies of actionable variants. Broader implementation requires rapid testing platforms, clinician education, tailored clinical guidelines, and real-world validation of aspirin, DOACs, and multi-gene approaches. Future research should expand population-specific studies and integrate pharmacogenomics within the broader framework of precision medicine to ensure equitable clinical benefit.

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.

The recent approval of trastuzumab deruxtecan for human epidermal growth factor receptor 2 (HER2)–low and HER2-ultralow breast cancer mandates an adequate assessment of these categories. Methods: Seven breast pathologists from the Breast Pathology Study Group of the Korean Society of Pathologists held an on-site expert consensus meeting. Fifteen sets of virtual whole slide images (WSI) of hematoxylin and eosin stain and HER2 immunohistochemistry were provided. The pathologists were given 60 minutes to submit their diagnosis of HER2 expression into null, ultralow, 1+, 2+, or 3+. Afterwards, in-depth discussion and consensus diagnoses were made by real-time visualization of the WSI. Results: After the consensus meeting, unanimous 100% agreements were seen only in five (33.3%) of the examined cases, which consisted of three 1+ cases and two 2+ cases. Two cases (13.3%) had mild disagreement, with only one pathologist’s disagreement. Of note, eight cases (53.3%) showed significant disagreement, defined by more than two pathologists’ disagreement. All HER2-null cases were reclassified as ultralow after consensus review, suggesting potential widespread underclassification of ultralow cases in clinical practice. Conclusions: Experts had significant discrepancies in interpreting HER2-low/ultralow status. It is important to assess if the distinction between HER2-low and ultralow is strictly required and if HER2-null breast cancer exists in reality.

Objective: This study aims to compare the incidence of active tuberculosis (TB) among Korean patients with rheumatoid arthritis (RA) initiating treatment with tumor necrosis factor inhibitors (TNFi) or tofacitinib. Methods: Using the Korean National Health Insurance database, we conducted a nationwide, retrospective cohort study of RA patients who started TNFi or tofacitinib therapy between 2015 and 2018. We calculated the incidence rates of active TB based on the treatment type and results from latent tuberculosis infection (LTBI) screening tests. A multivariable Cox proportional hazards model was employed to evaluate the risk of active TB in RA patients beginning TNFi or tofacitinib treatment. Results: Among 3,382 RA patients (596 on tofacitinib and 2,786 on TNFi), LTBI screening was predominantly conducted using the IGRA (interferon-gamma release assays) test. Of these patients, 624 (18.5%) with a positive LTBI test received prophylactic treatment. No cases of active TB occurred in tofacitinib users, while 32 cases were observed in TNFi users. The adjusted hazard ratio for active TB in LTBI-positive patients was 5.47 (95% confidence interval 2.74 to 10.92) compared to LTBI-negative patients.In subgroup analyses, TB incidence was significantly higher among individuals aged over 65 years. Conclusion Despite LTBI treatment, active TB remains prevalent among RA patients on TNFi therapy and in those with positive LTBI tests.

In forensic medicine, age estimation commonly involves assessing age-related changes in teeth and skeletal structures. Vertebral morphological alterations, such as osteophyte formation, serve as age indicators. Recent studies using deep-learning techniques, such as neural networks, for age estimation from radiographic images have been conducted, reporting significantly higher accuracy than previous studies. This study aimed to estimate age using neural network-based deep-learning techniques applied to computed tomography (CT) cross-sectional images of the spine and evaluate its feasibility. Postmortem CT scans of 214 cadavers with varying decomposition levels were used. Coronal and sagittal cross-sectional images penetrating the center of each vertebral body were extracted for the 11th and 12th thoracic vertebrae and the first to fifth lumbar vertebrae. Using these images, along with the chronological ages of deceased individuals, an age estimation model was developed through regression analysis in PyTorch, employing a convolutional neural networks architecture with five-fold cross-validation. The model achieved a mean absolute error of 5.385 years, root mean squared error of 7.029 years, and coefficient of determination of 0.793. Although the sample size was relatively small, the results suggested the potential applicability of vertebral imagingbased age estimation in the Korean population. Further research using a larger dataset may improve the accuracy and reliability of the model.