1.Unique TTR Variants D38A and M13dup Among Korean Patients with Hereditary Transthyretin Amyloidosis:A Retrospective Single-Center Cohort Study
Min-Seung PARK ; Jae Joon LEE ; Darae KIM ; Jin-Oh CHOI ; Seok Jin KIM ; Kihyun KIM ; Ju-Hong MIN ; Hyun-Young KIM ; Hee-Jin KIM
Annals of Laboratory Medicine 2026;46(3):309-318
Background:
Transthyretin amyloidosis, a protein-misfolding disorder characterized by systemic amyloid deposition, can be classified as wild-type transthyretin amyloidosis (ATTRwt) or hereditary transthyretin amyloidosis (ATTRv), depending on the presence of transthyretin (TTR) gene variants. We examined the genetic distribution of TTR variants in Korean patients diagnosed with ATTRv.
Methods:
We retrospectively reviewed 801 participants who underwent TTR analysis at Samsung Medical Center from 2012 to 2024. The participants were categorized into two groups: in-house probands or relatives, and externally referred probands or relatives.
Results:
Pathogenic or likely pathogenic TTR variants were detected in 36 of 165 in-house probands (21.8%), among which D38A was the most frequent variant (50.0%; 18/36), followed by M13dup and E89K (8.3% each). Among referred probands, D38A was predominant (54.5%; 12/22), followed by M13dup (22.7%; 5/22). Cardiac amyloid involvement was the most common manifestation, observed in 97.2% (35/36) of in-house probands with ATTRv, followed by peripheral nervous system (PNS; 94.4%) and autonomic nervous system (ANS; 88.9%) involvement. In contrast, ANS involvement was most prevalent among in-house relatives who underwent organ evaluation (61.5%; 24/39), followed by cardiac (52.1%; 25/48) and PNS (48.7%; 19/39) involvement. Five of the eight in-house relatives harboring M13dup (62.5%) showed organ involvement, primarily in the ANS, supporting the pathogenicity of this variant.
Conclusions
This study provides the largest single-institution dataset of Korean patients with ATTRv, incorporating systematic organ assessments. The predominance of the unique TTR variants D38A and M13dup delineates a distinct genetic landscape that may facilitate accurate and timely diagnosis of ATTRv in the Korean population.
2.Multicenter evaluation of the PASS score as a negative predictive tool and the impact of inter-observer variability in pheochromocytoma and paraganglioma risk stratification
Sungyeon JUNG ; Hye-Ri SHIN ; Su-Jin SHIN ; Hee Young NA ; Soon-Won HONG ; So Yeon PARK ; Chan Kwon JUNG ; Kyeong Cheon JUNG ; Young Lyun OH ; Jae-Kyung WON
Journal of Pathology and Translational Medicine 2026;60(2):202-213
The Pheochromocytoma of the Adrenal Gland Scaled Score (PASS) is widely used for risk stratification in pheochromocytoma and paraganglioma (PPGL), but its clinical utility is limited by inter-observer variability of its parameters and inconsistent predictive performance. Methods: We conducted a multicenter retrospective study of 1,518 patients with PPGL from five tertiary referral centers in Korea. Prognostic utility of PASS system was assessed using logistic regression, Kaplan-Meier analysis, and receiver operating characteristic (ROC) curve analysis. Inter-observer variability was inferred by comparing area under the ROC curve (AUCs) across institutions. Simplified PASS systems were developed based on multivariable analysis of key histopathological parameters. Results: The PASS system was a significant predictor of adverse events and recurrence-free survival. Although the PASS system demonstrated only modest discriminative ability (AUC, 0.673), it showed a high negative predictive value (NPV, 0.885), supporting its usefulness as a screening tool for benign behavior. However, there was significant inter-institutional variability in PASS performance (AUC; range, 0.513 to 0.727; p < .05). The 3-factor Simple PASS, which incorporates necrosis, spindling, and mitotic figures, exhibited less inter-observer variation. The 4-factor Simple PASS, which adds vascular invasion to the 3-factor model, also showed reduced inter-observer variability and improved AUC and NPV compared to the original PASS system. Conclusions: In this multicenter cohort, the PASS system demonstrated high NPV and screening potential, but significant inter-observer variability remains a challenge. Simplification of the PASS system and enhanced pathologist training may improve reproducibility and clinical utility in PPGL risk stratification.
3.Structural Transformation of the Korean Healthcare System to Protect National Health Rights:From the Perspective of Consumers and Primary Care
Mihwa YOO ; Hee Gyung KANG ; Jae-Heon KANG ; Minjoung KO ; Jong Myoung KIM ; Kunhee PARK ; Serng Bai PAK ; Chiwon SEO ; Junghee AHN ; Juhwan OH ; Eunyoung CHO ; Eun Jin HA
Korean Journal of Family Practice 2026;16(1):9-12
The South Korean healthcare system has achieved rapid quantitative growth; however, it continues to face critical challenges in ensuring the fundamental right to health of its citizens. From the perspective of healthcare consumers and civil society, this article identifies structural problems such as imbalances in medical accessibility, instability in essential and emergency care, and the limited participation of consumers in healthcare policy-making. Although the constitution stipulates the state’s responsibility to protect public health, current healthcare policies often prioritize administrative efficiency and provider-centered interests over patient experiences and health outcomes. In particular, this article argues that these challenges are closely related to the inadequate functioning of an accountable healthcare management framework. Structural failures in essential care, workforce shortages, and regional disparities are insufficiently monitored and addressed at the system level, resulting in responsibilities being blurred or shifted to individual healthcare providers. Consequently, the risks and burdens arising from systemic weaknesses are ultimately borne by citizens. To address these issues, this article emphasizes two major shifts. First, meaningful consumer participation must be institutionalized within healthcare governance to strengthen accountability, transparency, and responsiveness. Second, family medicine and primary care should be reinforced as the cornerstone of a sustainable, community-based healthcare system that ensures continuity of care, prevention, and chronic disease management. Re-establishing the healthcare system based on the right to health is not merely a technical adjustment, but a structural transformation toward a responsible and accountable system in which the state clearly assumes responsibility for monitoring, learning, and corrective action.
4.Current Status and Improvement Strategies for the Resident Training System in South Korea:Focusing on Patient Safety and Sustainable Healthcare
Seung-Won OH ; HaDa RYUOK ; Ilyoung OH ; Jae-Heon KANG ; Eun Jin HA ; Hee Gyung KANG ; Serng Bai PAK ; Junghee AHN ; Mihwa YOO ; Eunyoung CHO ; Juhwan OH
Korean Journal of Family Practice 2026;16(1):48-58
The South Korean resident training system is currently at a critical turning point, facing structural crises characterized by excessive labor-intensive environments and deteriorating quality of education. Since the medical standoff in 2024, the limitations of relying on junior doctors’ labor for hospital operations have become increasingly apparent. This review examines the current status and problems of the resident training system, including long working hours exceeding Organisation for Economic Co-operation and Development (OECD) standards, lack of systematic competency-based education, and worsening regional and essential medical imbalances. By analyzing international cases from the United States, United Kingdom, Japan, and Australia, this article proposes four core strategies for reform: (1) establishing a sustainable working and educational environment through the expansion of hospitalist systems and legalizing physician assistant roles; (2) innovating the curriculum and evaluation systems based on entrustable professional activities and milestones; (3) implementing a network-based training model to bridge the gap between metropolitan and regional healthcare; and (4) securing stable financial support and strengthening governance through the establishment of an independent evaluation body (e.g., K-ACGME). Ultimately, reforming the training system is essential not only for the rights and professional growth of residents but also for ensuring patient safety and the long-term sustainability of the national healthcare system.
5.Impact of Low-Density Lipoprotein Cholesterol Levels on Atherosclerotic Vascular Changes: Analysis of Korean Treat Stroke to Target Trial
Sang Hee HA ; Jae-Chan RYU ; Sung Hee AHN ; Jae-Kwan CHA ; Sang Min SUNG ; Tae-Jin SONG ; Kyung Bok LEE ; Eung-Gyu KIM ; Yong-Won KIM ; Ji Hoe HEO ; Man Seok PARK ; Kyusik KANG ; Byung-Chul LEE ; Keun-Sik HONG ; Oh Young BANG ; Jei KIM ; Jong S. KIM
Journal of Stroke 2026;28(2):330-333
6.Early Onset, High Comorbidity Burden, and Regional Disparities of CADASIL:A Nationwide Cohort Study in South Korea
Ju-Yeun LEE ; Minwoo LEE ; Jae-Sung LIM ; Mi Sun OH ; Kyung-Ho YU ; Young Eun KIM ; Hyeo-Il MA ; Yun Jin KIM ; Jong Ho PARK ; Young Hee JUNG
Journal of Clinical Neurology 2026;22(2):172-182
Background:
and Purpose To compare the epidemiological and clinical features of the rare patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) with age- and sex-matched controls in a nationwide cohort from South Korea.
Methods:
This observational cohort study analyzed newly diagnosed CADASIL patients aged at least 20 years and matched controls using data from the National Health Information Database for 2004–2022. The cumulative incidence of CADASIL was assessed by age and sex, and compared between regions. Neurologic and systemic diseases were compared between the CADASIL and control groups.
Results:
The study analyzed 816 CADASIL patients and 816 age- and sex-matched controls aged 56.8±15.2 years (mean±standard deviation), among whom 48.3% were male. The cumulative incidence of CADASIL was 1.86 per 100,000 people (95% confidence interval [CI]=1.85– 1.87 per 100,000), and peaked at 60–69 years of age. In terms of regional distribution, the incidence was highest for Jeju, at 39.67 per 100,000 (95% CI 37.84–41.49 per 100,000). Neurologic diseases were more frequent in CADASIL patients, including Alzheimer’s disease (33.1% vs.20.0%), vascular dementia (84.9% vs. 5.0%), epilepsy (34.6% vs. 15.9%), stroke (70.7% vs. 27.6%), parkinsonism (18.9% vs. 11.0%), and depression (60.8% vs. 44.9%). Systemic diseases such as diabetes mellitus (78.9% vs. 68.9%) were also more common in CADASIL patients, while cancer (27.9% vs. 38.7%) and myocardial infarction (10.0% vs. 13.6%) were less common than in controls. The onset ages of all diseases were lower in CADASIL patients.
Conclusions
This study has provided a precise nationwide estimate of the CADASIL incidence and its regional distribution in South Korea. CADASIL patients showed higher incidence rates and earlier onsets of diverse clinical manifestations.
7.Clinical Practice Guideline for the Prehospital Stage of Acute Stroke : III. Initial Decision for Primary Treatment in Subarachnoid Hemorrhage
Jae Sang OH ; Jong Min LEE ; Hong Suk AHN ; Jung-Jae KIM ; Kyoung Min JANG ; Gi-Yong YUN ; Jang Hun KIM ; Dongwook SEO ; Hyeong Jin LEE ; Yuna JO ; Jinwoo JEONG ; Kyoung-Chul CHA ; Yong Soo CHO ; Su Jin KIM ; Jongkyu PARK ; Won-Sang CHO ; Hoon KIM ; Young Woo KIM ; Seung Hun SHEEN ; Sang Weon LEE ; Jae Whan LEE ; Tae Gon KIM ; Sung-kon HA ; Sukh Que PARK ; Dae-Won KIM ; Soon Chan KWON
Journal of Korean Neurosurgical Society 2026;69(1):35-50
Subarachnoid hemorrhage (SAH) is a stroke subtype with high mortality and poor functional outcomes. Prompt occlusion of a ruptured aneurysm at an early stage is crucial to prevent rebleeding, which can result in even higher mortality and more severe disabilities. The most critical initial decision in SAH management is the choice of treatment method with surgical clipping or endovascular coiling. We aimed to develop an evidence-based clinical guideline to select the optimal initial treatment in patients with SAH. We developed this guideline based on evidence from systematic reviews and meta-analyses via a de novo process. A systematic literature review was conducted across four databases (MEDLINE, Embase, Cochrane, and KoreaMed) to answer two population, intervention, comparison, outcome questions comparing clipping and coiling. The risk of bias was assessed using ROB 2.0 and the Newcastle-Ottawa Scale. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagrams and meta-analyses were generated for functional outcome and mortality. We included six randomized control trials (RCTs) and 58 observational studies. Meta-analysis of RCTs showed that coiling improved functional outcomes compared to clipping (odds ratio [OR], 0.91; 95% confidence interval [CI], 0.86–0.97). No significant mortality difference was observed in RCTs (OR, 1.38; 95% CI, 0.91–2.09), but non-RCTs favored clipping for reduced mortality (OR, 0.77; 95% CI, 0.69–0.86). However, it is difficult to generalize these findings to all clinical situations, as patients with SAH have a highly variable clinical course. Final treatment decision should be tailored to the individual patient’s status, including aneurysm location, morphology, and the expertise available at the treatment center. Such decisions are best made by specialists such as a board-certified physician and should be explained to the patient and their caregivers, along with the rationale for selecting the most appropriate treatment at the given hospital. Korea has many certified endovascular neurosurgeons, cerebrovascular surgeons, and certified cerebrovascular centers. Proper selection of the most suitable treatment method by certified physicians and centers would greatly benefit patient outcomes and healthcare professionals.
8.Clinical Practice Guideline for the Prehospital Stage in Acute Stroke : I. Use of Emergency Medical Services Assessment Tools
Jae Sang OH ; Dongwook SEO ; Jinwoo JEONG ; Kyoung-Chul CHA ; Yong Soo CHO ; Su Jin KIM ; Jongkyu PARK ; Won-Sang CHO ; Se Won OH ; Jang Hun KIM ; Hyeong Jin LEE ; Hong Suk AHN ; Yuna JO ; Jung-Jae KIM ; Kyoung Min JANG ; Gi-Yong YUN ; Jong Min LEE ; Hoon KIM ; Young Woo KIM ; Tae Gon KIM ; Sung-kon HA ; Sukh Que PARK ; Soon Chan KWON
Journal of Korean Neurosurgical Society 2026;69(1):7-22
Accurate and early identification of stroke and large vessel occlusion (LVO) in emergency settings is essential for improving patient outcomes and ensuring the efficient allocation of medical resources. This clinical practice guideline systematically reviews domestic and international literature and conducts meta-analyses to evaluate the utility and diagnostic accuracy of stroke assessment tools used in prehospital emergency medical services (EMS). We developed a guideline based on evidence from systematic reviews and meta-analyses via a de novo process. A systematic literature review was conducted to evaluate the usefulness of diagnostic EMS assessment tools for diagnosing stroke and LVO. Overall, 70 non-randomized control studies were selected for this study. A meta-analysis was conducted with a subgroup analysis to distinguish between patients with stroke and those with LVO. EMS tools demonstrated high sensitivity but low specificity for diagnosing stroke. In the prehospital setting, using validated EMS stroke assessment tools is recommended for the early identification of stroke and LVO. Upon hospital arrival, stroke specialists should conduct further evaluation and triage to confirm the diagnosis and guide appropriate management. Delays in diagnosing LVO are frequently unacceptable. While experts advocate for the use of EMS assessment tools to facilitate early identification of LVO, these tools alone lack adequate sensitivity. Therefore, further diagnostic evaluations and consultation with stroke specialists upon hospital arrival are recommended.
9.Clinical Practice Guidelines for the Prehospital Stage of Acute Stroke in Korea II : Transport Decisions for Patients with Acute Ischemic Stroke
Jae Sang OH ; Yuna JO ; Jong Min LEE ; Hong Suk AHN ; Jung-Jae KIM ; Kyoung Min JANG ; Gi-Yong YUN ; Jang Hun KIM ; Dongwook SEO ; Hyeong Jin LEE ; Jinwoo JEONG ; Kyoung-Chul CHA ; Yong Soo CHO ; Su Jin KIM ; Jongkyu PARK ; Won-Sang CHO ; Hoon KIM ; Young Woo KIM ; Seung Hun SHEEN ; Sang Weon LEE ; Jae Whan LEE ; Tae Gon KIM ; Sung-kon HA ; Sukh Que PARK ; Soon Chan KWON
Journal of Korean Neurosurgical Society 2026;69(1):23-34
The mothership (MS) model, where patients are directly transferred to a thrombectomy-capable center, and the drip-and-ship (DS) model, where thrombolysis is initiated at the nearest primary stroke center before transfer for thrombectomy, are the primary transport modes for patients with stroke. We aimed to establish guidelines for selecting the appropriate transfer strategy based on emergent large vessel occlusion (LVO). We developed this guideline based on evidence from systematic reviews and meta-analyses via a de novo process. A systematic literature review was conducted across four databases (MEDLINE, Embase, Cochrane, and KoreaMed) to answer three Population, Intervention, Comparison, and Outcome questions comparing MS and DS models. The risk of bias was assessed using the Newcastle-Ottawa Scale. Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagrams and meta-analyses were generated for functional outcomes, mortality, and successful recanalization. Twenty-six non-randomized controlled studies showed that the MS model improved good functional outcomes by approximately 14% compared with the DS model (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.00–1.30). Fifteen studies reported that mortality in the MS and DS models showed no significant differences (OR, 0.97; 95% CI, 0.84–1.11). Twenty-four studies revealed no significant difference in successful recanalization between the MS and DS models (OR, 0.87; 95% CI, 0.68–1.10). The MS model should be considered first to improve the functional outcome of patients with LVO. However, if thrombectomy cannot be performed immediately after thrombolysis, or if a thrombectomy-enabled hospital is not nearby, the DS model should be considered by stroke specialists depending on transportation time and regional factors. We suggest a mixed approach with the DS model based on specific circumstances or regions to ensure the optimum treatment of patients with acute ischemic stroke (AIS). Appropriate transport for patients with LVO improves the prognosis of AIS.
10.Short-Segment Fixation with Anterior Support versus Long-Segment Fixation with Separation Surgery for Thoracolumbar Spinal Metastatic Tumors : A Comparative Analysis
Younggyu OH ; Subum LEE ; Jinuk KIM ; Seo Eun KIM ; Jae Hwan CHO ; Jin Hoon PARK
Journal of Korean Neurosurgical Society 2026;69(1):71-80
Objective:
: This study aims to evaluate and compare the clinical and radiographic outcomes of patients with metastatic spinal tumors who underwent either short-segment fixation with anterior support or long-segment fixation with a separation surgery in the thoracic or lumbar spine.
Methods:
: We conducted a retrospective analysis of adult patients who were treated surgically for spinal metastases in the thoracic or lumbar spine at a single tertiary referral center between April 2014 and December 2022. Surgical treatments included spinal cord decompression, short-segment fixation with maximal circumferential debulking of the lytic tumor portion and anterior support, or longsegment fixation without anterior support, followed by separation surgery and posterolateral fusion. We compared the two fixation strategies based on patient demographics, preoperative diagnoses, surgical data, neurological assessments, and changes in segmental Cobb angles immediately after surgery, and at the final follow-up.
Results:
: A total of 91 patients were included (short-segment, 44; long-segment, 47). No significant differences were observed between the groups regarding age, sex, comorbidities, primary cancer location, postoperative complications, or reoperation rates. Furthermore, no significant differences in the sagittal Cobb angles, including global angle (thoracic kyphosis, lumbar lordosis) and segmental angle were noted from the preop to the final follow-up. Compared to traditional long-segment fixation, short-segment fixation with anterior support significantly improved neurological outcomes in the thoracic region and reduced the length of hospital stay. No significant differences were observed between the two groups regarding complications or other clinical outcomes.
Conclusion
: Short-segment fixation is comparable to long-segment fixation in the management of thoracolumbar metastatic spinal tumors, with no significant differences in radiographic outcomes. However, short-segment fixation provides the added advantages of improved neurological outcomes in the thoracic region and shorter hospital stays.

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