Objectives: This study, part of the ongoing Korean National Burden of Disease (KNBD) updates, assesses disability-adjusted life years (DALYs) and disability-adjusted life expectancy (DALE) in Korea, taking into account the effects of coronavirus disease 2019 and emphasizing the importance of analyzing these metrics jointly. Methods: Data were obtained from Statistics Korea, the National Health Insurance Service, and the Korea Disease Control and Prevention Agency. DALYs and DALE were calculated using an incidence-based approach, following disease classification, disability weights, and estimation procedures consistent with prior KNBD research. Results: Compared with earlier estimates, DALYs showed a slight decline in 2020 followed by an increase in 2021, with this pattern observed across all income quintiles. For DALE, both men and women experienced modest gains relative to earlier studies; however, a decrease occurred across all income levels in 2021 compared with 2020. Regional disparities in DALE also narrowed beginning in 2020, with a more marked reduction among women. Conclusions Unlike previous studies, this research presents DALYs and DALE concurrently, offering a more comprehensive perspective on summary measures of population health. The post-2020 rise in DALYs underscores the growing need for effective chronic disease management. Additionally, widening income-based disparities in DALE highlight the urgency of addressing health inequities. Continued monitoring and updates of DALYs and DALE are necessary to understand and respond to these evolving trends.

Rotator cuff tears are a common musculoskeletal disorder that significantly impairs shoulder function, especially in the elderly. Traditionally, mechanical wear and age-related degeneration have been considered the leading causes. Recent studies, however, emphasize that systemic metabolic disorders, such as diabetes mellitus, obesity, and dyslipidemia, play a crucial role in the development and healing of rotator cuff disease. This narrative review comprehensively examines the biological mechanisms and clinical outcomes associated with these metabolic comorbidities in rotator cuff degeneration and surgical repair failure. Based on relevant clinical and experimental studies, this study analyzed how each metabolic disease contributes to tendon injury and impaired regeneration. Diabetes mellitus induces chronic inflammation, inhibits collagen synthesis, and impairs microvascular perfusion, hindering tendon healing. Obesity increases the mechanical load on the shoulder and promotes systemic inflammation, exacerbating fatty infiltration of muscles and delaying tissue repair. Dyslipidemia accelerates tendon degeneration through the accumulation of fat, oxidative stress, and fatty infiltration of the rotator cuff muscles. These systemic factors are associated with higher re-tear rates, delayed functional recovery, and poorer surgical outcomes. As the prevalence of metabolic syndrome increases, precise assessment and perioperative management of these metabolic disorders are essential to improve patient outcomes and develop personalized treatment strategies for rotator cuff tears.

Rotator cuff (RC) injuries cause degenerative changes, including muscle atrophy and fatty infiltration, which remain key pathophysiological factors limiting functional recovery and increasing the risk of re-tears even after surgical repair. In particular, these changes tend to progress to fibrofatty replacement over time, highlighting the limitations of surgery-focused treatments alone. Recent research has addressed this by increasingly focusing on biological therapeutic strategies that directly target the degenerative pathology of the RC muscle. This review article examines the current trends in preclinical and clinical research on three main biological approaches: stem cell-based tissue regeneration, modulation of pathological signaling pathways, and metabolic reprogramming strategies that restore the pathological metabolic environment. Building upon these pathophysiological foundations, this review aims to develop recent biological treatment strategies and explore their potential clinical applications.

In patients with differentiated thyroid cancer (DTC), initial recurrence risk stratification based on clinical, histopathological, and perioperative data remains the key determinant for guiding management strategies during the first 1-2 years post-treatment. However, the adoption of ongoing risk stratification (ORS), which dynamically reassesses risk by integrating longitudinal clinical data and treatment response, enables more precise long-term prognostic assessment and facilitates highly individualized management. Building upon recent guidelines, the 2026 KTA guideline has been further refined by incorporating robust evidence from large-scale national cohorts and comprehensive systematic reviews. These updated recommendations outline contemporary concepts of ORS, risk-adapted TSH suppression targets, optimized surveillance modalities for recurrence detection, and disease-specific long-term follow-up strategies. Reflecting the paradigm shift toward de-escalated treatment, this revision integrates evolved perspectives on TSH suppression intensity, the clinical interpretation of thyroglobulin levels, and tailored follow-up intervals. These evidence-based recommendations aim to minimize unnecessary treatment and excessive surveillance in the large proportion of patients with excellent prognosis after initial therapy, while ensuring that each patient receives appropriately tailored and effective long-term management.

The detrimental effects of hyperlipidemia on the healing of rotator cuff tears are well documented. The proposed underlying mechanisms for these effects include alterations in the extracellular matrix, inflammation, and oxidative stress, which hamper the reparative processes in the affected tendon tissues. Recent therapeutic strategies target these pathways, reflecting a growing body of research dedicated to mitigating these effects and promoting healing. This literature review aims to provide a comprehensive understanding of the pathophysiology underlying rotator cuff tears, examine the interplay between hyperlipidemia and rotator cuff tear healing, synthesize current knowledge on contributing biological mechanisms, and outline potential therapeutic interventions to optimize clinical management and treatment outcomes for patients.

Background: This study aimed to investigate changes after repeated subacromial drug injections in a rat model of normal rotator cuff. Methods: Thirty-nine male Sprague-Dawley rats were divided into groups 1 (no injection, n = 3), 2 (parecoxib, n = 18; 6 subgroups, n = 3 each; 0.5 mg/kg), and 3 (triamcinolone, n = 18; 6 subgroups, n = 3 each; 0.3 mg/kg). Groups 2 and 3 received subacromial injections 1–6 times once weekly for 6 weeks. The supraspinatus and infraspinatus tendons and muscles were used for biomechanical and histological evaluation. The subacromial bursa was used to analyze the prostaglandin E2 (PEG2) level. Results: In the biomechanical test, load-to-failure and ultimate stress decreased in groups 2 and 3 with repeated injections and the values were significantly lower in group 3 than in group 1 only at the sixth injection (p = 0.007 and p = 0.008, respectively). On the Bonar score, the cellularity, ground substance, and total score were significantly different among the 3 groups at the fifth and sixth injections (cellularity: p = 0.028 and p = 0.033, ground substance: p = 0.018 and p = 0.006, and total score: p = 0.029 and p = 0.027, respectively). The myocyte cross-sectional area of the infraspinatus muscle showed a significant difference among the 3 groups at the third and fourth injections (p = 0.031 and p = 0.020, respectively). The PEG2 level in the subacromial bursa was significantly different among the 3 groups at the third, fifth, and sixth injections (p = 0.019, p = 0.004, and p = 0.004, respectively). Conclusions In the rat model of normal rotator cuff, repeated local injections of the cyclooxygenase-2 inhibitor showed fewer negative effects on the biomechanical and histological properties of the normal tendon than triamcinolone.

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: Given that 40%-50% of primary central nervous system lymphoma (PCNSL) tissues exhibit aberrancy on 9p24.1, immune checkpoint inhibitors (ICI) may work for the disease. Materials and Methods: To define the role of ICIs in PCNSL, we carried out a nationwide retrospect analysis for 22 patients who had been treated with nivolumab monotherapy for relapsed or refractory PCNSL. Results: The median age at diagnosis was 66, and male: female ratio was 1:1. Patients received nivolumab after a median of 3 lines (range, 2 to 6) of therapy and at the median age of 67 years (range, 37 to 82 years). Eleven patients (50%) were refractory to the last treatment prior to nivolumab. With a median follow-up duration of 22.3 months (95% confidence interval [CI], 13.1 to 31.5), nine patients (41%) had an objective response (6 complete responses, 3 partial responses), and the median duration of response was 20.9 months (95% CI, 1.7 to 40.0). The median progression-free survival and overall survival were 2.1 months (95% CI, 0.2 to 4.0) and 18.9 months (95% CI, 5.0 to 32.8), respectively. Nivolumab was generally well-tolerated as no patients required dose reduction and only two patients required delay of treatment. Conclusion Our study suggests that nivolumab can be a reasonable option with the durable response for RR PCNSL.

Purpose: Given that 40%-50% of primary central nervous system lymphoma (PCNSL) tissues exhibit aberrancy on 9p24.1, immune checkpoint inhibitors (ICI) may work for the disease. Materials and Methods: To define the role of ICIs in PCNSL, we carried out a nationwide retrospect analysis for 22 patients who had been treated with nivolumab monotherapy for relapsed or refractory PCNSL. Results: The median age at diagnosis was 66, and male: female ratio was 1:1. Patients received nivolumab after a median of 3 lines (range, 2 to 6) of therapy and at the median age of 67 years (range, 37 to 82 years). Eleven patients (50%) were refractory to the last treatment prior to nivolumab. With a median follow-up duration of 22.3 months (95% confidence interval [CI], 13.1 to 31.5), nine patients (41%) had an objective response (6 complete responses, 3 partial responses), and the median duration of response was 20.9 months (95% CI, 1.7 to 40.0). The median progression-free survival and overall survival were 2.1 months (95% CI, 0.2 to 4.0) and 18.9 months (95% CI, 5.0 to 32.8), respectively. Nivolumab was generally well-tolerated as no patients required dose reduction and only two patients required delay of treatment. Conclusion Our study suggests that nivolumab can be a reasonable option with the durable response for RR PCNSL.

The detrimental effects of hyperlipidemia on the healing of rotator cuff tears are well documented. The proposed underlying mechanisms for these effects include alterations in the extracellular matrix, inflammation, and oxidative stress, which hamper the reparative processes in the affected tendon tissues. Recent therapeutic strategies target these pathways, reflecting a growing body of research dedicated to mitigating these effects and promoting healing. This literature review aims to provide a comprehensive understanding of the pathophysiology underlying rotator cuff tears, examine the interplay between hyperlipidemia and rotator cuff tear healing, synthesize current knowledge on contributing biological mechanisms, and outline potential therapeutic interventions to optimize clinical management and treatment outcomes for patients.