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.

Juvenile xanthogranuloma (JXG) is a histiocytic proliferative tumor that predominantly affects infants and young children. It is classified as a benign disease that comprises the majority of non-Langerhans cell histiocytes and is characterized by reddish-brown or yellow papules and nodules commonly found on the face and trunk. Although JXG presents with distinct clinical features, an exceedingly uncommon subset of JXG includes lesions that surpass 20 mm in diameter, referred to as giant JXG, which can occasionally be misdiagnosed as other tumors. Herein, we report a rare case of a giant JXG in a 1-month-old Korean boy, highlighting the significance of accurate diagnoses. Additionally, we provide a comprehensive literature review to enhance our understanding of this rare variant.

Prurigo pigmentosa (PP) is a rare inflammatory skin disease that commonly affects Asian women. It is characterized by symmetric pruritic eruptions in a reticular pattern, primarily on the back, chest, or neck. The etiology of PP is unclear; however, it is estimated that neutrophil-mediated inflammation of the skin is induced by various exogenous stressors, such as friction from clothing and sweating. In addition to exogenous factors, some cases are thought to be related to ketosis, diabetes mellitus, fasting, or dieting to lose weight. With the increasing popularity of ketogenic diets, cases of PP are being more commonly reported. To raise awareness of this disease, we present two cases of PP that occurred after following a ketogenic diet.

Erythema nodosum (EN) is the most common form of panniculitis and may be triggered by a variety of stimuli, including infections, drugs, pregnancy, sarcoidosis, inflammatory bowel disease, and malignancies. Rare cases of vaccination-related EN have been reported, but none due to the coronavirus disease 2019 (COVID-19) vaccine of Pfizer have been documented. We report a case of EN associated with the Pfizer vaccine. A 43-year-old woman presented with acute-onset painful nodular lesions that appeared bilaterally on the extensor surface of the lower legs. These lesions appeared 5 days after the first dose of Pfizer vaccination. The patient reported no recent infectious history other than fever for 3 days after vaccination. Skin biopsy revealed inflammation extending into the subcutaneous fat with a septal distribution. It is important for physicians to be aware of the side effects of the COVID-19 vaccine because more people are bound to be vaccinated.

Background: and Purpose We aimed to develop a model predicting early recanalization after intravenous tissue plasminogen activator (t-PA) treatment in large-vessel occlusion. Methods: Using data from two different multicenter prospective cohorts, we determined the factors associated with early recanalization immediately after t-PA in stroke patients with large-vessel occlusion, and developed and validated a prediction model for early recanalization. Clot volume was semiautomatically measured on thin-section computed tomography using software, and the degree of collaterals was determined using the Tan score. Follow-up angiographic studies were performed immediately after t-PA treatment to assess early recanalization. Results: Early recanalization, assessed 61.0±44.7 minutes after t-PA bolus, was achieved in 15.5% (15/97) in the derivation cohort and in 10.5% (8/76) in the validation cohort. Clot volume (odds ratio [OR], 0.979; 95% confidence interval [CI], 0.961 to 0.997; P=0.020) and good collaterals (OR, 6.129; 95% CI, 1.592 to 23.594; P=0.008) were significant factors associated with early recanalization. The area under the curve (AUC) of the model including clot volume was 0.819 (95% CI, 0.720 to 0.917) and 0.842 (95% CI, 0.746 to 0.938) in the derivation and validation cohorts, respectively. The AUC improved when good collaterals were added (derivation cohort: AUC, 0.876; 95% CI, 0.802 to 0.950; P=0.164; validation cohort: AUC, 0.949; 95% CI, 0.886 to 1.000; P=0.036). The integrated discrimination improvement also showed significantly improved prediction (0.097; 95% CI, 0.009 to 0.185; P=0.032). Conclusions The model using clot volume and collaterals predicted early recanalization after intravenous t-PA and had a high performance. This model may aid in determining the recanalization treatment strategy in stroke patients with large-vessel occlusion.

Background: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are potentially fatal acute hypersensitivity reactions that involve the skin and mucous membranes. Because they are relatively rare diseases, it is difficult to obtain well-organized epidemiological data. The clinicodemographic characteristics, culprit drugs, and factors related to disease prognosis may vary. Objective: To identify the characteristics of SJS/TEN by investigating patient clinicopathological characteristics, laboratory findings, suspected drugs, and mortality through a retrospective study using medical record data. Methods: The clinical records of patients diagnosed with SJS/TEN between February 2009 and February 2019 at three medical institutions of Soonchunhyang University were retrospectively reviewed. Data pertaining to sex, age, history, suspected drugs, latent period, laboratory findings, and mortality were collected, and their correlations were analyzed. Results: We identified SJS/TEN in 88 patients. Among the probable causative agents, antibiotics were the most common (29 cases, 33.0%), followed by nonsteroidal anti-inflammatory drugs (NSAIDs) in 20 cases (22.7%). The period between drug administration and symptom onset varied with the causative agent. Patients who died had high SCORTEN scores. In addition, hypertension, diabetes, renal failure, and cardiac disease had a statistically significant association with high SCORTEN. Conclusion Antibiotics, NSAIDs, antiepileptics and allopurinol were the most commonly implicated drugs in our retrospective study. There was a significant correlation between comorbidities. Because SJS/TEN is a life-threatening condition, early recognition of the suspected drug are important. The results of this study may provide insights that aid in the early diagnosis and prediction of disease outcomes of SJS/TEN in the Korean population.

Background: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are potentially fatal acute hypersensitivity reactions that involve the skin and mucous membranes. Because they are relatively rare diseases, it is difficult to obtain well-organized epidemiological data. The clinicodemographic characteristics, culprit drugs, and factors related to disease prognosis may vary. Objective: To identify the characteristics of SJS/TEN by investigating patient clinicopathological characteristics, laboratory findings, suspected drugs, and mortality through a retrospective study using medical record data. Methods: The clinical records of patients diagnosed with SJS/TEN between February 2009 and February 2019 at three medical institutions of Soonchunhyang University were retrospectively reviewed. Data pertaining to sex, age, history, suspected drugs, latent period, laboratory findings, and mortality were collected, and their correlations were analyzed. Results: We identified SJS/TEN in 88 patients. Among the probable causative agents, antibiotics were the most common (29 cases, 33.0%), followed by nonsteroidal anti-inflammatory drugs (NSAIDs) in 20 cases (22.7%). The period between drug administration and symptom onset varied with the causative agent. Patients who died had high SCORTEN scores. In addition, hypertension, diabetes, renal failure, and cardiac disease had a statistically significant association with high SCORTEN. Conclusion Antibiotics, NSAIDs, antiepileptics and allopurinol were the most commonly implicated drugs in our retrospective study. There was a significant correlation between comorbidities. Because SJS/TEN is a life-threatening condition, early recognition of the suspected drug are important. The results of this study may provide insights that aid in the early diagnosis and prediction of disease outcomes of SJS/TEN in the Korean population.