Varicella, caused by the varicella-zoster virus, was once nearly universal in childhood before the advent of vaccination and may lead to severe complications and even fatalities. Monitoring varicella vaccine effectiveness is crucial yet often overlooked in settings with limited surveillance infrastructure. The Korean Varicella Immunization Monitoring (K-VIM) Scheme was established to address this gap by assembling a national, insurance-based birth cohort of children born between 2011 and 2022 (n=4,505,165). This cohort leverages comprehensive healthcare databases in Korea to capture vaccination records, medical visits, and varicella infection outcomes for virtually all children within the target birth years. We describe the enrollment and key characteristics of the K-VIM cohort, including vaccination coverage, demographic features, and varicella incidence to date. The structure and completeness of Korea’s national health insurance and immunization registries enable robust longitudinal tracking of varicella infections among vaccinated versus unvaccinated children. Early findings demonstrate distinct patterns in infection rates and disease severity according to vaccination status. The K-VIM Scheme provides a foundation for ongoing epidemiological studies of varicella vaccine effectiveness and public health impact in Korea. Future plans include evaluating the long-term effects of varicella vaccination, including potential impacts on herpes zoster incidence, using diverse study designs to strengthen causal inference and inform immunization policy.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Purpose: Bilateral axillo-breast approach robotic parathyroidectomy (BABA-RP) aims to remove overactive or enlarged parathyroid glands with no visible neck collar incision. In this study, we compared the safety and surgical outcomes of BABA-RP vs. those of an open surgery group to ascertain whether BABA-RP is a safe and feasible surgical approach for patients with primary hyperparathyroidism (pHPT). Methods: This single-institution retrospective cohort study included 74 patients with primary HPT who underwent open parathyroidectomy (n = 37) or BABA-RP (n = 37) at our institution between November 2014 and March 2023. Patient demographics, biochemical cure rates, operative time, blood loss rates, and complication rates were examined and compared. Results: The patients in the BABA-RP group were younger and had a longer mean operative time. Regarding complication events, 2 patients in the open surgery group and 1 patient in the BABA-RP group had transient hypoparathyroidism. All 74 patients achieved biochemical cure at <6 months, regardless of the approach used. Two patients in the BABA-RP group and 1 patient in the open surgery group had carcinoma on surgical pathology. All 3 patients with parathyroid carcinoma remained recurrence-free at 1-year follow-up. Conclusion Compared with the open procedure, BABA-RP is a safe and feasible procedure that provides an excellent biochemical cure rate for patients with pHPT and has superior cosmetic benefits with equivalent surgical outcomes.

Background: Global Lung Function Initiative (GLI)-2012 reference equation is currently suggested for interpretation of spirometry results and a new local reference equation has been developed in South Korea. However, lung function profiles according to the different reference equations and their clinical relevance have not been identified in chronic obstructive pulmonary disease (COPD) patients. Methods: Our cross-sectional study evaluated Choi’s, Korean National Health and National Examination Survey (KNHANES)-VI, and GLI-2012 reference equations. We estimated the percentages of predictive forced expiratory volume in one second (FEV 1) and airflow limitation severity according to reference equations and analyzed their associations with patient reported outcomes (PROs): COPD assessment test (CAT) score, St. George's Respiratory Questionnaire for COPD patients (SGRQ-C) score, and six minute walk distance (6MWD). Results: In the eligible 2,180 COPD patients, lower predicted values of FEV 1 and forced vital capacity (FVC) were found in GLI-2012 compared to Choi's and KNHANES-VI equations.GLI-2012 equation resulted in a lower proportion of patients being classified as FEV 1 < 80% or FVC < 80% compared to the other equations. However, the Z-scores of FEV 1 and FVC were similar between the KNHANES-VI and GLI-2012 equations. Three reference equations exhibited significant associations between FEV 1 (%) and patient-reported outcomes (CAT score, SGRQ-C score, and 6MWD). Conclusion GLI-2012 reference equation may not accurately reflect FEV 1 (%) in the Korean population, but the Z-score using GLI-2012 equation can be a viable option for assessing FEV 1 and airflow limitation in COPD patients. Similar to the other two equations, the GLI-2012 equation demonstrated significant associations with PROs.

Purpose: We compared the surgical outcomes of radical nephrectomy (RN) and partial nephrectomy (PN) in adult patients with clinical T2 stage (cT2) renal cell carcinoma (RCC) by utilizing data from the Korean Renal Cell Carcinoma (KORCC) database. Materials and Methods: We retrospectively analyzed adult patients with cT2 RCC from 8 tertiary hospitals who were registered in the KORCC between 2003 and 2023. Patients with a solitary kidney or bilateral tumors were excluded. The patient cohort was divided into RN and PN arms, and propensity score matching (PSM) was conducted with a 1:3 ratio. Perioperative and survival outcomes were compared between arms. Results: After PSM, the PN and RN arms included 44 and 132 patients, respectively. No significant differences were observed in baseline characteristics, apart from laterality, following PSM. Regarding perioperative outcomes, complications of Clavien-Dindo classification grade III or higher (11.4%, p<0.001) and urological complications (9.1%, p=0.045) were more common in the PN arm than in the RN arm. Postoperative renal function was superior in the PN arm, whereas the incidence of de novo chronic kidney disease (CKD) at 6 months was higher among the recipients of RN (37.6%, p<0.001). Pathological examination indicated a higher pathological T stage in the RN arm. Overall, cancer-specific, and recurrence-free survival rates did not differ significantly between arms. Based on Cox regression analysis, the use of PN was not a significant predictor of recurrence-free survival (hazard ratio, 0.675; p=0.474). Conclusions In cT2 RCC, PN was associated with a lower incidence of de novo CKD than RN. No significant differences in survival outcomes were noted. PN may represent a viable alternative to RN for certain patients with cT2 RCC. Further research is warranted to explore the management of advanced RCC.

In mid-2022, as the wave of pediatric coronavirus disease 2019 (COVID-19) cases escalated in South Korea, a public-private partnership was made to establish a Pediatric COVID-19 Module Clinic (PMC). We describe the utilization of the first prototype children’s modular clinic in Korea University Anam Hospital functioning as the COVID-19 PMC. Between August 1 and September 30, 2022, a total of 766 children visited COVID-19 PMC. Daily number of patient visits to the COVID-19 PMC ranged between 10 and 47 in August; and less than 13 patients per day in September 2022. Not only the model provided timely care for the COVID-19 pediatric patients, but it also enabled safe and efficacious care for the non-COVID-19 patients in the main hospital building while minimizing exposure risk to severe acute respiratory syndrome coronavirus 2 transmission. Current description highlights the importance of spatial measures for mitigating in-hospital transmission of COVID-19, in specifically on pediatric care.

Purpose: As thyroid cancer patients are experiencing longer disease-free survival periods, evaluating their quality of life after surgery has become crucial. However, studies on this topic have primarily focused on Western populations, leaving a gap in understanding the Korean patient population’s experiences and needs. This study aims to address this gap and provide insights into the quality of life of thyroid cancer patients in Korea. Methods: This cross-sectional study evaluated the quality of life of Korean thyroid cancer patients who underwent thyroid lobectomy or total thyroidectomy. Patients were surveyed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ-C30, ver. 3.0) during outpatient clinic visits from January to September 2015. The results were analyzed by comparing them to scores of the general population and based on the time elapsed since surgery. This approach allowed for a comprehensive evaluation of the quality-of-life outcomes in this patient population. Results: The study found that thyroidectomy had a notable impact on patients’ role and cognitive functions. Patients also experienced worsened symptoms such as fatigue, dyspnea, and constipation, which improved over time and returned to normal levels. However, there were no significant changes in other functions and symptoms after surgery. Conclusion The study’s findings showed that thyroidectomy had a relatively minor impact on the functional and symptomatic well-being of patients. Therefore, the results suggest that thyroid surgery may be a safe and effective treatment option for thyroid cancer patients seeking to maintain a good quality of life.