Background: and Purpose The relationship between thrombus histology and long-term stroke patient outcomes remains unexplored. We aimed to determine whether the histological characteristics of thrombi are associated with long-term outcomes in stroke patients and to identify the thrombus features linked to these outcomes. Methods: This retrospective multicenter cohort study included 512 patients with ischemic stroke who underwent endovascular thrombectomy between July 2017 and July 2023. Patients were followed up for long-term major adverse cardiovascular events occurrence. Thrombus histology was assessed using immunohistochemistry, including the proportion of fibrin, red blood cells, and platelets, as well as the distribution patterns categorized as layered, erythrocytic, diffuse platelet, and mixed. Results: During a median follow-up of 38.1 months, 164 patients experienced major adverse cardiovascular events, with an incidence rate of 3.02 per 100 person-years. Major adverse cardiovascular events occurrence was associated with the diffuse platelet pattern and proportion of platelets and red blood cells within the thrombus. After adjusting for confounders, the diffuse platelet pattern independently predicted major adverse cardiovascular events, including mortality and stroke recurrence. Subgroup analysis also demonstrated that the association between the diffuse platelet pattern and major adverse cardiovascular events was consistent across key clinical subgroups based on age (≥65 vs. <65 yr), atrial fibrillation, cancer status, and discharge medications. Conclusions Thrombus histology could provide predictive value for long-term prognosis. In particular, histological distribution patterns may be more important than simple composition in thrombus research, including in the prediction of prognosis.

Objectives: This study was performed to quantify the impact of coronavirus disease 2019 (COVID-19) on hospital profitability in Korea by analyzing changes in the medical revenue-to-profit ratio (MRPR) and net income before reserve fund allocation (NIBR) before and after the pandemic onset. Additionally, it examined how financial outcomes varied by hospital ownership, geographic location, and type (secondary or tertiary), providing insights into the financial resilience of various hospital types during public health crises. Methods: We conducted a longitudinal analysis using publicly available financial disclosure data from 243 general hospitals in Korea (2016–2022). We then performed a quadrant analysis to classify hospitals based on changes in MRPR and NIBR, identifying patterns of financial impact. For inferential analysis, we employed linear mixed-effects models incorporating a difference-in-differences framework, enabling estimation of both time-varying and hospital-specific effects. Results: Following the onset of COVID-19, MRPR declined significantly, reaching −10.62% in 2020. NIBR initially dropped but later increased, reaching 21.09 billion Korean won per 100 beds in 2022. Quadrant analysis revealed substantial heterogeneity in financial responses, with national/public hospitals experiencing the most severe MRPR decline, whereas educational foundation and medical corporation hospitals displayed stronger financial recovery. Regression results confirmed significant interactions between outcomes after COVID-19 onset and hospital ownership type, indicating differential financial impacts across hospital categories. Conclusions The findings highlight the uneven financial effects of COVID-19 on Korean hospitals, emphasizing the importance of targeted government financial support. Policy measures should prioritize structural financial reforms to ensure hospital sustainability beyond short-term crisis management.

Purpose: To investigate the clinical characteristics, onset timing, and anatomical and functional outcomes of MEK inhibitor–associated retinopathy (MEKAR) in Korean patients receiving systemic MEK inhibitor therapy. Methods: This retrospective study included 16 patients diagnosed with MEKAR between January 2011 and August 2025. Best-corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal choroidal thickness (CT), and optical coherence tomography (OCT) findings were evaluated at baseline, at MEKAR onset, and at final follow-up. Results: Mean age was 57.8 ± 10.6 years, with a male predominance (68.8%). Colorectal cancer was the most common primary malignancy (56.3%), followed by lung cancer and malignant melanoma (18.7% each). MEKAR developed after a median of 3.3 weeks (IQR, 1.9–4.4 weeks) following therapy initiation, and the median time to initial improvement was 2.4 weeks (IQR, 1.3–8.1 weeks). At onset, 62.6% of patients reported ocular symptoms, while 37.4% were asymptomatic. OCT showed reversible retinal changes, most commonly ellipsoid zone thickening (68.8%) and focal subretinal fluid (43.8%), all of which resolved completely. CMT increased transiently at onset compared with baseline (p = 0.002) and normalized at final follow-up (p < 0.001), with no baseline–final difference (p = 0.489). CT remained stable (p = 0.159). BCVA was preserved, with a median of 0.00 logMAR at baseline, onset and final follow-up. Patients undergoing dose modification or interruption showed faster improvement than those continuing therapy (median, 9 vs. 81 days; p = 0.004). One patient showed multiple recurrent episodes, all of which resolved without visual deterioration. Conclusions MEKAR developed early after treatment initiation and followed a transient, fully reversible course with preserved visual function. Although dose modification accelerated anatomical recovery, long-term outcomes remained favorable even with continued therapy, supporting close monitoring and individualized management rather than routine interruption, particularly in mild or asymptomatic cases.

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.

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.

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.

Purpose: Triple-negative breast cancer (TNBC) is a frequent phenotype of BRCA-mutanttumors. Tumors with BRCAness may show characteristics of BRCA-mutant tumors and respond to similar treatments. Next-generation sequencing is an efficient and cost-effective method for simultaneously sequencing multiple cancer susceptibility genes, surpassing conventional Sanger testing. Methods: A total of 148 women with TNBC were recruited from December 2015 to November 2018, as part of a sub-analysis based on the PEARLY trial data. Of them, 103 patients received neoadjuvant chemotherapy (NCT). The targeted genes related to hereditary cancers were sequenced using the 65-gene germline next-generation sequencing (gNGS) panel pathogenic and likely pathogenic variants (P&LPs) were determined by Sanger sequencing. We examined the occurrence of pathologic complete remission (ypCR) in patients with P&LPs. Results: The patients’ median age was 47 years (range, 27–69 years). Twenty (13.7%) of 148 patients had P&LP in six genes, including BARD1 (n = 2), BRCA1 (n = 9), BRCA2 (n = 5), CHEK2 (n = 1), RAD51C (n = 1), and RAD51D (n = 2). Among the 103 patients with NCT, 43 (41.7%) achieved ypCR (P&LPs; 9 individuals vs. non-variants; 34 individuals). Among the 103 patients with NCT, 14 (9.3%) had P&LPs. Nine of 14 patients with P&LPs, including BARD1 (n = 2), BRCA1 (n = 4), BRCA2 (n = 1), RAD51C (n = 1), and RAD51D (n = 1), achieved ypCR, showing a trend toward statistical significance (p = 0.066). Conclusion Germline P&LP mutations in TNBC patients can be detected by gNGS. This panel test can identify BRCA and BRCAness mutations that may predict ypCR in TNBC.

Purpose: The novel curability criteria for elderly (EL) patients have been proposed to stratify their risk of lymph node metastasis (LNM), following non-curative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). Hence, this study aimed to evaluate the effectiveness of the EL criteria and compare them with those of the well-known eCura system. Materials and Methods: A retrospective analysis was performed on 143 patients who did not meet the curative ESD criteria at a tertiary hospital in Korea between 2011 and 2022. Of these, 102 underwent additional surgery, while 41 were followed up without further treatment. The LNM rates based on the EL and eCura systems were stratified and compared. Results: In the surgery group, 29.4% (30/102) patients were classified as EL-low (EL-L) and 70.2% (72/102) as EL-high (EL-H). The LNM rates (95% confidence interval) were 0.0% (0.0–11.6) and 9.7% (4.0–19.0) for EL-L and EL-H, respectively (P=0.102). EL-L was closely aligned with the eCura low-risk category, with a similar patient proportion (32.4%) and an LNM rate of 0.0% (0.0–10.6). The eCura system classified 94.1% (48/51) of the EL-L patients as lowrisk, with an 86% concordance rate (123/143). Discordant cases included patients with positive vertical margins, but without other risk factors, who were classified as EL-H without LNM. Conclusions Patients with EL-L showed no LNM, and the EL criteria demonstrated high concordance with the eCura system. The EL criteria may be as effective as the eCura system in identifying low-risk patients after non-curative ESD for EGC.

Background: Group B Streptococcus (GBS) is one of the leading causes of neonatal earlyonset sepsis, resulting in high mortality and significant comorbidity. Intrapartum penicillin prophylaxis is recommended for pregnant women with GBS colonization to prevent vertical transmission. For pregnant women at high risk of anaphylaxis to penicillin, clindamycin is recommended only if the susceptibility of GBS isolates has been identified. We retrospectively examined the GBS detection rate and clindamycin resistance among Korean women of reproductive age over the last 20 years. Methods: Microbiologic studies using vaginal, vaginal–rectal or vaginal–perianal swabs from female patients 15–49 years of age during 2003–2022 were reviewed. Annual GBS detection rates and clindamycin resistance rates were calculated. The study period was divided into two periods (period 1, 2003–2015; period 2, 2016–2022) based on the introduction of universal culture-based GBS screening in our center in 2016. GBS detection rates and clindamycin resistance rates were compared between the periods using χ2 tests. Results: A total of 14,571 women were tested 16,879 times and GBS was isolated in 1,054 tests (6.2%), with 423 clindamycin-resistant isolates (40.1%). The GBS detection rate increased from 3.4% (301/8,869) in period 1 to 9.4% (2,753/8,010) in period 2 (P < 0.001). Even during period 1, the GBS detection rate was higher in 2009–2015 compared to 2003–2008 (P < 0.001). Clindamycin resistance rates have remained at similar levels since 2009, which were 39.5% (199/301) in period 1 and 40.2% (303/753) in period 2 (P = 0.833). Conclusion This study demonstrated that GBS detection rates in Korean women of reproductive age significantly increased almost three times during the twenty years of the study period, with a persistently high clindamycin resistance rate of up to 40%.

Background/Aims: As the number of lower gastrointestinal endoscopies and high-risk examinees increases, the incidence of adverse events associated with these endoscopies has also increased. Medical disputes and lawsuits related to adverse events are rapidly increasing. Methods: Medical disputes related to lower gastrointestinal endoscopy that had been filed in Korean Medical Dispute Mediation and Arbitration Agency (K-medi) from April 2012 to August 2020 were evaluated with the corresponding medical records and written appraisal. Facilities, patients, procedures, adverse events, and outcome-related variables related to medical disputes were analyzed. Results: As the number of lower gastrointestinal endoscopies in Korea increases each year, the number of medical disputes related to lower gastrointestinal endoscopy appraised by K-medi has also increased yearly during the same period. Among the 121 cases analyzed, 86 (71.1%) were conciliated and 35 (28.9%) were cosigned by prosecution. Perforations accounted for the largest proportion of cases (93 cases, 76.9%). Most patients (n = 119, 98.3%) underwent non-emergent procedures, and only 10 (8.3%) underwent them for therapeutic purposes. Approximately one-fifth of the patients (n = 25, 20.7%) died. Conclusions The number of medical disputes related to lower gastrointestinal endoscopy are increasing. To prevent this, it is important to review the data on existing cases and establish specific response guidelines.