Purpose: Radiotherapy is used to reduce the risk of breast cancer recurrence after surgery, but it is a potential cause of secondary cancer. We validated the risk of secondary cancer in primary breast cancer who received radiotherapy compared with those who did not from a matched cohort using a large-scale observational study of the Observational Health Data Sciences and Informatics (OHDSI) data network. Materials and Methods: A retrospective comparative cohort study using propensity score-matched cohorts was performed using two Observational Medical Outcome Partnership common data model databases, from tertiary general hospitals in South Korea. Among female patients who underwent surgery after the diagnosis of breast cancer, the risk of secondary primary malignant occurrence after 1:1 matching was analyzed. Results: Among 27,078 patients with breast cancer, there was no significant difference in the risk of secondary cancer following radiotherapy in 4,426 patients after 1:1 propensity-score matching. Further, there were no significant differences in the sensitivity analysis according to age, latency period, and number of radiation treatments. Conclusion There was no difference in the risk of secondary cancer in the patients diagnosed with breast cancer depending on whether or not radiotherapy was performed after surgery. In the future, it is necessary to analyze including data generated during cancer treatment.

Objective: To explain process of developing basic veterinary clinical performance guidelines, based on frequently observable clinical manifestations, thereby supporting competencybased veterinary education in Korea. Methods: A structured review of learning outcomes established by Korean Association of Veterinary Medical Colleges (KAVMC) was conducted by a planning committee including veterinary educators, practitioners, and advisory members. Owner-oriented descriptions were used to frame each performance task, and each was mapped to corresponding learning outcomes. These tasks were aligned with learning outcomes recommended by the KAVMC to support the development of communication, clinical reasoning, and performance-related competencies among veterinary students, thereby enhancing day-one clinical readiness. Results: In total, 63 clinical manifestations for a guidebook format that can be used for clinical education were identified and categorized by organ systems that are described in language understandable to animal owners. Conclusions and Relevance: The basic veterinary clinical performance guidelines based on common clinical manifestations would serve as a vital component in veterinary education to reinforce core graduation competencies.

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: 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: 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.

Purpose: Fish allergy is rare in children, and there have been few studies on childhood fish allergy. This study aims to investigate the clinical characteristics and laboratory findings of white meat fish (WMF) allergy in Korean children. Methods: In this study, we enrolled 150 children with a history of WMF consumption who underwent serum specific immunoglobulin E to cod (cod-sIgE) at Ajou University Hospital from January 2019 to December 2022. The demographic characteristics, clinical symptoms, history of consuming 6 major Korean WMF (cod, cutlass, yellow croaker, brown sole, olive flounder, and anchovy), and cod-sIgE were investigated. Results: Sixty-five subjects (43.3%) had clinical responses to at least 1 of the 6 WMF (WMF-allergic), and 85 subjects had no allergic reaction to all 6 WMF (WMF-tolerant). The median age of first symptom onset in the WMF-allergic group was 15 months. Major causative WMF were yellow croaker (30.6%), cutlass (28.7%), cod (26.1%), brown sole (20.4%), anchovy (14.7%), and olive flounder (6.5%). Twenty-three of 65 WMF-allergic children (35.4%) had anaphylaxis. The median level of cod-sIgE was 4.61 kUA/L (range, 0.04–100.10 kUA/L) in the WMF-allergic group, and this value was significantly higher (P < 0.001) than that of the WMF-tolerant group (0.04 kUA/L; range, 0.04–3.08 kUA/L). The positive rates ( ≥ class 2, 0.7 kUA/L) of cod-sIgE for the 6 individual WMF ranged from 69% to 90%. Conclusion We propose that WMF allergy can develop in young children, with 35.4% experiencing anaphylaxis. Cod-sIgE is considered a useful tool for diagnosing not only cod allergy but also other WMF allergy in children.

Purpose: Fish allergy is the ninth common food allergy, and cutlassfish is one of the common allergenic fishes in Korean children.However, there is no commercial diagnostic tool for testing cutlassfish allergy in the world. We evaluated the usefulness of serum cod specific IgE (cod-sIgE) to diagnose cutlassfish allergy and cross-reaction between cutlassfish and cod. Methods: Nineteen children who experienced immediate type reactions after consumption of cutlassfish were enrolled. Cod-sIgE was measured by ImmunoCAP, and serum samples were obtained from 11 allergic patients and 11 controls. Using our own homemade crude extracts, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), anti-parvalbumin (PV) immunoglobulin G immunoblot, enzyme-linked immunosorbent assay (ELISA), and ELISA inhibition were performed. Results: Thirteen patients were clinically allergic to both cutlassfish and cod, and 6 were allergic to cutlassfish alone. The median age and cod-sIgE concentrations were not significantly different between the 2 groups. The clear fish protein bands and PVs were identified on SDS-PAGE and immunoblotting. Serum cod-sIgE was positive in 4 out of 6 cutlassfish mono-allergic patients, however, there was no significant correlation between cod-sIgE by ImmunoCAP and cutlassfish-specific IgE by ELISA. The cutlassfish IgE ELISA was profoundly inhibited by cutlassfish, while the cod IgE ELISA was profoundly inhibited by cod but partially inhibited by cutlassfish. Conclusion We found a potential diagnostic value of cod-sIgE to diagnose cutlassfish allergy and the asymmetric cross-reaction between cutlassfish and cod. These results could help diagnose and provide a dietary guidance in cutlassfish allergic children.

Purpose: This study aimed to validate the Korean version of the Global Interprofessional Therapeutic Communication Scale (K-GITCS), with the ultimate goal of improving therapeutic communication and patient engagement among Korean nurses. Methods: The study rigorously adhered to the original authors’ translation guidelines. A sample of 300 registered nurses from a tertiary hospital in South Korea participated in this research. Confirmatory factor analysis was conducted to verify the tool’s validity, and Cronbach’s ⍺ coefficients were calculated to evaluate the internal consistency of the K-GITCS. Results: The instrument’s reliability was substantiated by an adequate comparative fit index (0.984) and a high Cronbach’s ⍺ coefficient (0.94). The empirical results supported the three-factor structure of the K-GITCS, which comprised trust and rapport building, power sharing, and empathy. Conclusion The study confirms that the K-GITCS is a valid, reliable, and culturally sensitive instrument for assessing therapeutic communication skills among nurses in Korea. It also highlights the importance of culturally tailored therapeutic communication training, particularly for promoting empathy in patient care. The study emphasizes the potential of the K-GITCS to significantly enhance nurses’ therapeutic communication practices, thereby improving the quality and safety of patient care. It is recommended to apply this tool among nursing students, academic institutions, and interprofessional healthcare providers to facilitate structured educational interventions that will improve therapeutic communication.

The decision to discontinue intensive care unit (ICU) treatment during the end-oflife stage has recently become a significant concern in Korea, with an observed increase in life-sustaining treatment (LST) withdrawal. There is a growing demand for evidence-based support for patients, families, and clinicians in making LST decisions. This study aimed to identify factors influencing LST decisions in ICU inpatients and to analyze their impact on healthcare utilization. Methods: We retrospectively reviewed medical records of ICU patients with neurological disorders, infectious disorders, or cancer who were treated at a single university hospital between January 1, 2019 and July 7, 2021. Factors influencing the decision to withdraw LST were compared between those who withdrew LST and those who did not. Results: Among 54,699 hospital admissions, LST was withdrawn in 550 cases (1%). Cancer was the most common diagnosis, followed by pneumonia and cerebral infarction. Among ICU inpatients, LST was withdrawn from 215 (withdrawal group). The withdrawal group was older (78 vs. 75 years, P=0.002), had longer total hospital stays (16 vs. 11 days, P<0.001), and higher ICU readmission rates than the control group. There were no significant differences in the healthcare costs of ICU stay between the two groups. Most LST decisions (86%) were made by family. Conclusions: The decisions to withdraw LST of ICU inpatients were influenced by age, readmission, and disease category. ICU costs were similar between the withdrawal and control groups. Further research is needed to tailor LST decisions in the ICU.

The decision to discontinue intensive care unit (ICU) treatment during the end-oflife stage has recently become a significant concern in Korea, with an observed increase in life-sustaining treatment (LST) withdrawal. There is a growing demand for evidence-based support for patients, families, and clinicians in making LST decisions. This study aimed to identify factors influencing LST decisions in ICU inpatients and to analyze their impact on healthcare utilization. Methods: We retrospectively reviewed medical records of ICU patients with neurological disorders, infectious disorders, or cancer who were treated at a single university hospital between January 1, 2019 and July 7, 2021. Factors influencing the decision to withdraw LST were compared between those who withdrew LST and those who did not. Results: Among 54,699 hospital admissions, LST was withdrawn in 550 cases (1%). Cancer was the most common diagnosis, followed by pneumonia and cerebral infarction. Among ICU inpatients, LST was withdrawn from 215 (withdrawal group). The withdrawal group was older (78 vs. 75 years, P=0.002), had longer total hospital stays (16 vs. 11 days, P<0.001), and higher ICU readmission rates than the control group. There were no significant differences in the healthcare costs of ICU stay between the two groups. Most LST decisions (86%) were made by family. Conclusions: The decisions to withdraw LST of ICU inpatients were influenced by age, readmission, and disease category. ICU costs were similar between the withdrawal and control groups. Further research is needed to tailor LST decisions in the ICU.