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.

Background: The rapid increase in the number of coronavirus disease (COVID-19) patients led to the operation of COVID-19 facilities for patients with mild COVID-19 in South Korea. We analyzed the correlation and effect of risk factors associated with the worsening of patients with mild COVID-19 leading to their transfer from a community treatment center to a hospital. Methods: This retrospective cohort observational study included 1,208 COVID-19 patients with mild symptoms who were admitted to the Namsan Community Treatment Center between June 2020 and January 2021. A chi-square test was performed to examine the differences in the transfer rate by age, sex, nationality, presence of symptoms at admission, and season, and a multivariable logistic regression analysis was performed to examine the association of variables to the hospitalization rate. Results: Of the 1,208 patients, 212 (17.5%) were transferred to a hospital due to clinical deterioration. Increasing odds of hospital transfer were associated significantly with higher age and presentation in autumn, whereas sex and symptomatic illness at admission did not show a statistically significant association. Conclusion The findings indicate the importance of the initial risk classification of COVID-19 patients based on thorough assessment and close monitoring, timely allocation of appropriate resources to high-risk groups that are likely to develop severe disease, and reduction of medical resource wastage and limiting of administrative force to ensure that patients receive the best treatment.

Background: In response to the disaster of coronavirus disease 2019 (COVID-19) pandemic, Seoul Metropolitan Government (SMG) established a patient facility for mild condition patients other than hospital. This study was conducted to investigate the operation and necessary resources of a community treatment center (CTC) operated in Seoul, a metropolitan city with a population of 10 million. Methods: To respond COVID-19 epidemic, the SMG designated 5 municipal hospitals as dedicated COVID-19 hospitals and implemented one CTC cooperated with the Boramae Municipal Hospital for COVID-19 patients in Seoul. As a retrospective cross-sectional observational study, retrospective medical records review was conducted for patients admitted to the Seoul CTC. The admission and discharge route of CTC patients were investigated. The patient characteristics were compared according to route of discharge whether the patient was discharged to home or transferred to hospital. To report the operation of CTC, the daily mean number of tests (reverse transcription polymerase chain reaction and chest X-ray) and consultations by medical staffs were calculated per week. The list of frequent used medications and who used medication most frequently were investigated. Results: Until May 27 when the Seoul CTC was closed, 26.5% (n = 213) of total 803 COVID-19 patients in Seoul were admitted to the CTC. It was 35.7% (n = 213) of 597 newly diagnosed patients in Seoul during the 11 weeks of operation. The median length of stay was 21 days (interquartile range, 12–29 days). A total of 191 patients (89.7%) were discharged to home after virologic remission and 22 (10.3%) were transferred to hospital for further treatment.Fifty percent of transferred patients were within a week since CTC admission. Daily 2.5–3.6consultations by doctors or nurses and 0.4–0.9 tests were provided to one patient. The most frequently prescribed medication was symptomatic medication for COVID-19 (cough/ sputum and rhinorrhea). The next ranking was psychiatric medication for sleep problem and depression/anxiety, which was prescribed more than digestive drug. Conclusion In the time of an infectious disease disaster, a metropolitan city can operate a temporary patient facility such as CTC to make a surge capacity and appropriately allocate scarce medical resource.

Until now microsatellite (MS) have been a popular choice of markers for parentage verification. Recently many countries have moved or are in process of moving from MS markers to single nucleotide polymorphism (SNP) markers for parentage testing. FAO-ISAG has also come up with a panel of 200 SNPs to replace the use of MS markers in parentage verification. However, in many countries most of the animals were genotyped by MS markers till now and the sudden shift to SNP markers will render the data of those animals useless. As National Institute of Animal Science in South Korea plans to move from standard ISAG recommended MS markers to SNPs, it faces the dilemma of exclusion of old animals that were genotyped by MS markers. Thus to facilitate this shift from MS to SNPs, such that the existing animals with MS data could still be used for parentage verification, this study was performed. In the current study we performed imputation of MS markers from the SNPs in the 500-kb region of the MS marker on either side. This method will provide an easy option for the labs to combine the data from the old and the current set of animals. It will be a cost efficient replacement of genotyping with the additional markers. We used 1,480 Hanwoo animals with both the MS data and SNP data to impute in the validation animals. We also compared the imputation accuracy between BovineSNP50 and BovineHD BeadChip. In our study the genotype concordance of 40% and 43% was observed in the BovineSNP50 and BovineHD BeadChip respectively.
Animals ; Cattle ; Genotype ; Korea* ; Methods ; Microsatellite Repeats* ; Polymorphism, Single Nucleotide

BACKGROUND AND OBJECTIVES: Tympanostomy tube insertion is one of the most common surgical procedures in children. Despite aseptic procedures with prophylactic antibiotic treatment, postoperative otorrhea may be encountered in some patients. The purpose of this study is to identify the relation between the types of immune cells in otitis media with effusion (OME) and tympanostomy tube otorrhea (TTO) in children. SUBJECTS AND METHOD: Fifty-six patients underwent tympanostomy tube insertion with OME were analyzed retrospectively. Fluid from OME was harvested by suction via syringe connector after myringotomy. Light microscopic examination of middle ear effusion was performed by a pathologist after hematoxylin and eosin staining. We analyzed the relation between the types of immune cells from middle ear effusion and TTO. RESULTS: Of 56 children, 36 were male and 22 were female. The mean age for tympanostomy tube insertion was 3.56 (±2.63) years, with the average follow-up period of 12.56 (±9.96) months. Neutrophils were detected in 19, eosinophils in 14, lymphocytes in 22, mast cells in 2, plasma cells in 7, and histiocytes in 9. TTO occurred in 15 patients. In patients with early TTO, eosinophils were detected more frequently than in patients without TTO (p=0.006). Plasma cells were detected more frequently in patient with late TTO than without TTO (p=0.011). CONCLUSION: According to the analysis of different types of immune cells, eosinophils in the middle ear effusion related with the occurrence of TTO.
Child* ; Ear, Middle* ; Eosine Yellowish-(YS) ; Eosinophils ; Female ; Follow-Up Studies ; Hematoxylin ; Histiocytes ; Humans ; Lymphocytes ; Male ; Mast Cells ; Methods ; Middle Ear Ventilation* ; Neutrophils ; Otitis Media with Effusion* ; Otitis Media* ; Otitis* ; Plasma Cells ; Retrospective Studies ; Suction ; Syringes

PURPOSE: Gallstone formation is one of the most common problems after gastrectomy. This retrospective cohort study used the South Korean nationwide claims database to evaluate the incidence and risk factors of gallstone after gastrectomy for gastric cancer. METHODS: All consecutive patients who underwent gastrectomy for gastric cancer in South Korea in 2008–2010 were identified. Incidence of gallstone formation 5 years after gastrectomy in males and females, in various age groups, and after different types of gastrectomy was determined. Multivariate logistic regression analysis served to identify gallstone risk factors. RESULTS: Of the 47,752 patients, 2,506 (5.2%) developed gallstone during the 5-year follow-up period. At 12, 24, 36, and 48 months, the cumulative incidences were 1.2%, 2.2%, 3.3%, and 4.3%, respectively. Males had a higher incidence than females (5.8% vs. 4.1%, P < 0.001). Older patients (60–89 years) had a higher incidence than younger patients (30–59 years) (6.1% vs. 4.3%, P < 0.001). Gallstone was most common after total gastrectomy (6.6%), followed by proximal gastrectomy (5.4%), distal gastrectomy (4.8%), and pylorus-preserving distal gastrectomy (4.0%) (P < 0.001). Multivariate analysis showed that male sex (odds ratio [OR], 1.39), an older age (OR, 1.44), and total gastrectomy (OR, 1.40 vs. distal gastrectomy) were significant independent risk factors for postgastrectomy gallstone. CONCLUSION: The cumulative incidence of gallstone 5 years after gastrectomy for gastric cancer was 5.2%. Male sex, an older age, and total gastrectomy were significant risk factors. More careful monitoring for gallstone may be necessary in patients with such risk factors.
Cholecystectomy ; Cohort Studies ; Female ; Follow-Up Studies ; Gallstones* ; Gastrectomy ; Humans ; Incidence* ; Korea ; Logistic Models ; Male ; Multivariate Analysis ; Retrospective Studies ; Risk Factors ; Stomach Neoplasms*

PURPOSE: The preoperative diagnosis of acute appendicitis is often challenging. Sometimes, pathologic results of the appendix embarrass or confuse surgeons. Therefore, more and more imaging studies are being performed to increase the accuracy of appendicitis diagnoses preoperatively. However, data on the effect of this increase in preoperative imaging studies on diagnostic accuracy are limited. We performed this study to explore unexpected appendiceal pathologies and to delineate the role of preoperative imaging studies in the diagnosis of acute appendicitis. METHODS: The medical records of 4,673 patients who underwent an appendectomy for assumed appendicitis between 1997 and 2012 were reviewed retrospectively. Pathological results and preoperative imaging studies were surveyed, and the frequencies of pathological results and preoperative imaging studies were investigated. RESULTS: The overall rate of pathology compatible with acute appendicitis was 84.4%. Unexpected pathological findings, such as normal histology, specific inflammations other than acute appendicitis, neoplastic lesions, and other pathologies, comprised 9.6%, 3.3%, 1.2%, and 1.5%, respectively. The rate of unexpected pathological results was significantly reduced because of the increase in preoperative imaging studies. The decrease in normal appendices contributed the most to the reduction while other unexpected pathologies did not change significantly despite the increased use of imaging studies. This decrease in normal appendices was significant in both male and female patients under the age of 60 years, but the differences in females were more prominent. CONCLUSION: Unexpected appendiceal pathologies comprised 15.6% of the cases. Preoperative imaging studies reduced them by decreasing the negative appendectomy rate of patients with normal appendices.
Appendectomy ; Appendicitis ; Appendix ; Diagnosis ; Female ; Humans ; Inflammation ; Male ; Medical Records ; Pathology* ; Retrospective Studies ; Surgeons