The importance of considering competing risks in recurrence analysis of intracranial meningioma.

BACKGROUND: The risk of recurrence is overestimated by the Kaplan-Meier method when competing events, such as death without recurrence, are present. Such overestimation can be avoided by using the Aalen-Johansen method, which is a direct extension of Kaplan-Meier that accounts for competing events. Meningiomas commonly occur in older individuals and have slow-growing properties, thereby warranting competing risk analysis. The extent to which competing events are considered in meningioma literature is unknown, and the consequences of using incorrect methodologies in meningioma recurrence risk analysis have not been investigated. METHODS: We surveyed articles indexed on PubMed since 2020 to assess the usage of competing risk analysis in recent meningioma literature. To compare recurrence risk estimates obtained through Kaplan-Meier and Aalen-Johansen methods, we applied our international database comprising ~ 8,000 patients with a primary meningioma collected from 42 institutions. RESULTS: Of 513 articles, 169 were eligible for full-text screening. There were 6,537 eligible cases from our PERNS database. The discrepancy between the results obtained by Kaplan-Meier and Aalen-Johansen was negligible among low-grade lesions and younger individuals. The discrepancy increased substantially in the patient groups associated with higher rates of competing events (older patients with high-grade lesions). CONCLUSION: The importance of considering competing events in recurrence risk analysis is poorly recognized as only 6% of the studies we surveyed employed Aalen-Johansen analyses. Consequently, most of the previous literature has overestimated the risk of recurrence. The overestimation was negligible for studies involving low-grade lesions in younger individuals; however, overestimation might have been substantial for studies on high-grade lesions.

Fully Automated Continuous Centrifugal Microfluidics Isolates Natural Killer Cells with High Performance and Minimal Stress.

Natural killer (NK) cells are a part of the innate immune system, providing the first line of defense against cancer cells and pathogens at an early stage. Hence, they are attracting attention as a valuable resource for allogeneic cell immunotherapy. However, NK cells exist with limited proportion in blood, and obtaining sufficient clinical-grade NK cells with highly viable and minimal stress is critical for successful immune cell therapy. Conventional purification methods via immunoaffinity or density gradient centrifugation had several limitations in yield, purity, and cellular stress, which might cause an increased risk for graft versus host disease and reduced efficacy due to NK cell malfunction, exhaustion, and apoptosis. Moreover, reducing the variations of isolation performance caused by the manual process is another unmet need for uniform quality of the living drug. Here, an automated system using an NK disc (NKD) based on continuous centrifugal microfluidics (CCM) technology was developed to isolate NK cells from whole blood with high yield, purity, reproducibility, and low stress. The CCM technology, which operates fluidic manipulation under disc rotation, enabled precise extraction of the ultra-thin target fluid layer generated by blood centrifugation. Compared to the conventional manual method, the CCM-NKD isolated NK cells with higher yield (recovery rate) and purity, while maintaining better reproducibility. Furthermore, since the CCM-NKD maintained substantially milder centrifugation conditions (120 ×g for 10 min) compared to the conventional approach (1200 ×g for 20 min), it showed reduced cellular stress and increased antioxidant capacity in the isolated NK cells. Based on the results, the CCM-NKD is expected to be a useful tool to provide highly intact and viable cell weapons for successful immune cell therapy.

Epigenetic Regulation of the Expression of T Cell Stimulatory and Inhibitory Factors by Histone H3 Lysine Modification Enzymes and Its Prognostic Roles in Glioblastoma.

BACKGROUND: This study aimed to identify the specific T cell co-stimulatory and co-inhibitory factors that play prognostic roles in patients with glioblastoma. Additionally, the unique histone H3 modification enzymes that regulate the expression levels of these specific co-stimulatory and co-inhibitory factors were investigated. METHODS: The medical records of 84 patients newly diagnosed with glioblastoma at our institution from January 2006 to December 2020 were retrospectively reviewed. Immunohistochemical (IHC) staining for T cell co-stimulatory factors (CD27, CD28, CD137, OX40, and ICOS), T cell co-inhibitory factors (CTLA4, PD1, PD-L1, TIM3, and CD200R), and histone H3 lysine modification enzymes (MLL4, RIZ, EZH1, NSD2, KDM5c, JMJD1a, UTX, and JMJD5) was performed on archived paraffin-embedded tissues obtained by biopsy or resection. Quantitative real time-polymerase chain reaction (qRT-PCR) was performed for specific factors, which demonstrated causal relationships, in order to validate the findings of the IHC examinations. RESULTS: The mean follow-up duration was 27.5 months (range, 4.1-43.5 months). During this period, 76 patients (90.5%) died, and the mean OS was 19.4 months (95% confidence interval, 16.3-20.9 months). Linear positive correlations were observed between the expression levels of CD28 and JMJD1a (R2 linear = 0.982) and those of CD137 and UTX (R2 linear = 1.528). Alternatively, significant negative correlations were observed between the expression levels of CTLA4 and RIZ (R2 linear = -1.746) and those of PD-L1 and EZH1 (R2 linear = -2.118); these relationships were confirmed by qRT-PCR. In the multivariate analysis, increased expression levels of CD28 (P = 0.042), and CD137 (P = 0.009), and decreased expression levels of CTLA4 (P = 0.003), PD-L1 (P = 0.020), and EZH1 (P = 0.040) were significantly associated with longer survival. CONCLUSION: These findings suggest that the expression of certain T cell co-stimulatory factors, such as CD28 and CD 137, and co-inhibitory factors, such as CTLA4 and PD-L1 are associated with prognosis of glioblastoma patients.

Comparative Analysis of the Patients with Spontaneous Thalamic Hemorrhage with Concurrent Intraventricular Hemorrhage and Those without Intraventricular Hemorrhage.

BACKGROUND: This study aimed to compare the characteristics of patients with spontaneous thalamic hemorrhage (STH) accompanied by intraventricular hemorrhage (IVH) with those of patients without IVH. METHODS: The medical records of consecutive patients with STH admitted to our institute between January 2000 and December 2018 were reviewed retrospectively. The laboratory and radiological results, mortality, and functional recovery were compared between the STH patients with IVH and those without IVH. RESULTS: Among 2,389 patients with spontaneous intracerebral hemorrhage, 233 (9.8%) patients were included in this study. Concurrent IVH was detected in 159 (68.2%) patients with STH, and more frequently in those with body mass index ≥ 25, Glasgow Coma Scale score of 3-8, underlying disease, family history of stoke, posterior/medial/global location of hematoma, ventriculomegaly, large volume of hemorrhage, and midline shift ≥ 5 mm. The 3-month mortality was 25.8% and 8.1% (P = 0.039), the rate of good functional recovery at 6 months was 52.2% and 31.0% (P = 0.040), and incidence of delayed normal pressure hydrocephalus (NPH) at 12 months was 10.8% and 24.5% (P = 0.062) in the STH patients with IVH and those without IVH, respectively. At 12 months, delayed NPH developed in 28 of 47 (59.6%) patients who received external ventricular drainage (EVD)-based treatment, 5 of 45 (11.1%) patients who underwent endoscopic evacuation-based treatment, and 8 of 45 (17.8%) patients who underwent other surgeries. CONCLUSION: Concurrent IVH is strongly associated with mortality in patients with STH. Delayed NPH may develop more frequently in STH patients with IVH who were treated with EVD.

Association of Aortic Arch Calcification on Chest X-ray with Procedural Thromboembolism after Mechanical Thrombectomy for Acute Ischemic Stroke.

Background and Objective: Procedural thromboembolism after a mechanical thrombectomy (MT) for an acute ischemic stroke (AIS) has rarely been studied. It may occur from the artery-to-artery embolization of atherosclerotic plaque in the aortic arch. We investigated the relationship between aortic arch calcification (AoAC) on a chest X-ray and procedural thromboembolism on diffusion-weighted imaging (DWI) after an MT. Materials and Methods: From January 2017 to December 2020, 131 patients underwent DWI within two days following an MT for an AIS. Procedural thromboembolism was defined as new DWI-positive lesions in other territories from the occluded artery on DWI within two days after MT. Results: Procedural thromboembolism was observed in 30 (22.9%) patients. Procedural thromboembolism was associated with old age (72.3 ± 9.44 vs. 65.7 ± 12.8 years, p = 0.003), a longer procedural time (77.6 ± 37.6 vs. 60.1 ± 29.7 min, p = 0.024), and AoAC (calcification (73.3%) vs. no calcification (29.7%), p < 0.001). Multivariable logistic regression analysis showed that procedural thromboembolism was independently associated with AoAC (adjusted odds ratio (OR): 6.107, adjusted 95% confidence interval (CI): 2.374-15.705, p < 0.001) and a longer procedural time (adjusted OR: 1.015, adjusted 95% CI: 1.001-1.030, p = 0.031). Conclusions: Procedural thromboembolism after an MT for an AIS was related to AoAC on a chest X-ray and a longer procedural time. Our results suggest that although rapid recanalization is the most crucial goal of an MT for an AIS, the importance of the careful advance of the guiding catheter through the aortic arch should not be underestimated to reduce the risk of procedural thromboembolism, especially in patients with AoAC on a chest X-ray.

Factors Associated with Procedural Thromboembolisms after Mechanical Thrombectomy for Acute Ischemic Stroke.

Background and objective: Procedural thromboembolisms after mechanical thrombectomy (MT) for acute ischemic stroke has rarely been studied. We retrospectively evaluated factors associated with procedural thromboembolisms after MT using diffusion-weight imaging (DWI) within 2 days of MT. Materials and Methods: From January 2018 to March 2020, 78 patients with acute ischemic stroke who underwent MT were evaluated using DWI. Procedural thromboembolisms were defined as new cerebral infarctions in other territories from the occluded artery on DWI after MT. Results: Procedural thromboembolisms were observed on DWI in 16 patients (20.5%). Procedural thromboembolisms were associated with old age (73.8 ± 8.18 vs. 66.8 ± 11.2 years, p = 0.021), intravenous (IV) thrombolysis (12 out of 16 (75.0%) vs. 25 out of 62 (40.3%), p = 0.023), heparinization (4 out of 16 (25.0%) vs. 37 out of 62 (59.7%), p = 0.023), and longer procedural time (90.9 ± 35.6 vs. 64.4 ± 33.0 min, p = 0.006). Multivariable logistic regression analysis revealed that procedural thromboembolisms were independently associated with procedural time (adjusted odds ratio (OR); 1.020, 95% confidence interval (CI); 1.002-1.039, p = 0.030) and IV thrombolysis (adjusted OR; 4.697, 95% CI; 1.223-18.042, p = 0.024). The cutoff value of procedural time for predicting procedural thromboembolisms was ≥71 min (area under the curve; 0.711, 95% CI; 0.570-0.851, p = 0.010). Conclusions: Procedural thromboembolisms after MT for acute ischemic stroke are significantly associated with longer procedural time and IV thrombolysis. This study suggests that patients with IV thrombolysis and longer procedural time (≥71 min) are at a higher risk of procedural thromboembolisms after MT for acute ischemic stroke.

Cell Seeding Technology for Microarray-Based Quantitative Human Primary Skeletal Muscle Cell Analysis.

Pipetting techniques play a crucial role in obtaining reproducible and reliable results, especially when seeding cells on small target areas, such as on microarrays, biochips or microfabricated cell culture systems. For very rare cells, such as human primary skeletal muscle cells (skMCs), manual (freehand) cell seeding techniques invariably result in nonuniform cell spreading and heterogeneous cell densities, giving rise to undesirable variations in myogenesis and differentiation. To prevent such technique-dependent variation, we have designed and fabricated a simple, low-cost pipet guidance device (PGD), and holder that works with hand-held pipettes. This work validates the accuracy and reproducibility of the PGD platform and compares its effectiveness with manual and robotic seeding techniques. The PGD system ensures reproducibility of cell seeding, comparable to that of more expensive robotic dispensing systems, resulting in a high degree of cell uniformity and homogeneous cell densities, while also enabling cell community studies. As compared to freehand pipetting, PGD-assisted seeding of C2C12 mouse myoblasts showed 5.3 times more myotube formation and likewise myotubes derived from PGD-seeded human primary skMCs were 3.6 times thicker and 2.2 times longer. These results show that this novel, yet simple PGD-assisted pipetting technique provides precise cell seeding on small targets, ensuring reproducible and reliable high-throughput cell assays.

A feedback loop comprising PRMT7 and miR-24-2 interplays with Oct4, Nanog, Klf4 and c-Myc to regulate stemness.

Self-renewal and pluripotency are two fundamental characteristics of embryonic stem cells (ESCs) and are controlled by diverse regulatory factors, including pluripotent factors, epigenetic regulators and microRNAs (miRNAs). Although histone methyltransferases are key epigenetic regulators, whether and how a histone methyltransferase forms a network with miRNAs and the core pluripotent factor system to regulate ESC stemness is little known. Here, we show that the protein arginine methyltransferase 7 (PRMT7) is a pluripotent factor essential for the stemness of mouse ESCs. PRMT7 repressed the miR-24-2 gene encoding miR-24-3p and miR-24-2-5p by upregulating the levels of symmetrically dimethylated H4R3. Notably, miR-24-3p targeted the 3' untranslated regions (UTRs) of the major pluripotent factors Oct4, Nanog, Klf4 and c-Myc, whereas miR-24-2-5p silenced Klf4 and c-Myc expression. miR-24-3p and miR-24-2-5p also targeted the 3'UTR of their repressor gene Prmt7 miR-24-3p and miR-24-2-5p induced mouse ESC differentiation, and their anti-sense inhibitors substantially reversed spontaneous differentiation of PRMT7-depleted mouse ESCs. Oct4, Nanog, Klf4 and c-Myc positively regulated Prmt7 expression. These findings define miR-24-3p and miR-24-2-5p as new anti-pluripotent miRNAs and also reveal a novel epigenetic stemness-regulatory mechanism in which a double-negative feedback loop consisting of PRMT7 and miR-24-3p/miR24-2-5p interplays with Oct4, Nanog, Klf4 and c-Myc to control ESC stemness.

An essential role for UTX in resolution and activation of bivalent promoters.

Trimethylated histone H3 lysine 27 (H3K27me3) is linked to gene silencing, whereas H3K4me3 is associated with gene activation. These two marks frequently co-occupy gene promoters, forming bivalent domains. Bivalency signifies repressed but activatable states of gene expression and can be resolved to active, H3K4me3-prevalent states during multiple cellular processes, including differentiation, development and epithelial mesenchymal transition. However, the molecular mechanism underlying bivalency resolution remains largely unknown. Here, we show that the H3K27 demethylase UTX (also called KDM6A) is required for the resolution and activation of numerous retinoic acid (RA)-inducible bivalent genes during the RA-driven differentiation of mouse embryonic stem cells (ESCs). Notably, UTX loss in mouse ESCs inhibited the RA-driven bivalency resolution and activation of most developmentally critical homeobox (Hox) a-d genes. The UTX-mediated resolution and activation of many bivalent Hox genes during mouse ESC differentiation were recapitulated during RA-driven differentiation of human NT2/D1 embryonal carcinoma cells. In support of the importance of UTX in bivalency resolution, Utx-null mouse ESCs and UTX-depleted NT2/D1 cells displayed defects in RA-driven cellular differentiation. Our results define UTX as a bivalency-resolving histone modifier necessary for stem cell differentiation.

A clinical analysis of brain metastasis in gynecologic cancer: a retrospective multi-institute analysis.

This study analyzes the clinical characteristics of the brain metastasis (BM) of gynecologic cancer based on the type of cancer. In addition, the study examines the factors influencing the survival. Total 61 BM patients of gynecologic cancer were analyzed retrospectively from January 2000 to December 2012 in terms of clinical and radiological characteristics by using medical and radiological records from three university hospitals. There were 19 (31.1%) uterine cancers, 32 (52.5%) ovarian cancers, and 10 (16.4%) cervical cancers. The mean interval to BM was 25.4 months (21.6 months in ovarian cancer, 27.8 months in uterine cancer, and 33.1 months in cervical cancer). The mean survival from BM was 16.7 months (14.1 months in ovarian cancer, 23.3 months in uterine cancer, and 8.8 months in cervical cancer). According to a multivariate analysis of factors influencing survival, type of primary cancer, Karnofsky performance score, status of primary cancer, recursive partitioning analysis class, and treatment modality, particularly combined therapies, were significantly related to the overall survival. These results suggest that, in addition to traditional prognostic factors in BM, multiple treatment methods such as neurosurgery and combined chemoradiotherapy may play an important role in prolonging the survival for BM patients of gynecologic cancer.

Epigenetic Role of Histone 3 Lysine Methyltransferase and Demethylase in Regulating Apoptosis Predicting the Recurrence of Atypical Meningioma.

Alteration of apoptosis is related with progression and recurrence of atypical meningiomas (AMs). However, no comprehensive study has been conducted regarding histone modification regulating apoptosis in AMs. This study aimed to determine the prognostic values of certain apoptosis-associated factors, and examine the role of histone modification on apoptosis in AMs. The medical records of 67 patients with AMs, as diagnosed during recent 13 yr, were reviewed retrospectively. Immunohistochemical staining was performed on archived paraffin-embedded tissues for pro-apoptotic factors (CASP3, IGFBP, TRAIL-R1, BAX, and XAF1), anti-apoptotic factors (survivin, ERK, RAF1, MDM2, and BCL2), and the histone modifying enzymes (MLL2, RIZ, EZH1, NSD2, KDM5c, JMJD2a, UTX, and JMJD5). Twenty-six (38.8%) patients recurred during the follow-up period (mean duration 47.7 months). In terms of time-to-recurrence (TTR), overexpression of CASP3, TRAIL-R1, and BAX had a longer TTR than low expression, and overexpression of survivin, MDM2, and BCL2 had a shorter TTR than low expression (P<0.05). Additionally, overexpression of MLL2, UTX, and JMJ5 had shorter TTRs than low expression, and overexpression of KDM5c had a longer TTR than low expression. However, in the multi-variate analysis of predicting factors for recurrence, low expression of CASP3 (P<0.001), and BAX (P<0.001), and overexpression of survivin (P=0.007), and MDM2 (P=0.037) were associated with recurrence independently, but any enzymes modifying histone were not associated with recurrence. Conclusively, this study suggests certain apoptosis-associated factors should be associated with recurrence of AMs, which may be regulated epigenetically by histone modifying enzymes.

Recent Trends in the Withdrawal of Life-Sustaining Treatment in Patients with Acute Cerebrovascular Disease : 2017-2021.

OBJECTIVE: The Act on Life-Sustaining Treatment (LST) decisions for end-of-life patients has been effective since February 2018. An increasing number of patients and their families want to withhold or withdraw from LST when medical futility is expected. This study aimed to investigate the status of the Act on LST decisions for patients with acute cerebrovascular disease at a single hospital. METHODS: Between January 2017 and December 2021, 227 patients with acute cerebrovascular diseases, including hemorrhagic stroke (n=184) and ischemic stroke (n=43), died at the hospital. The study period was divided into the periods before and after the Act. RESULTS: The duration of hospitalization decreased after the Act was implemented compared to before (15.9±16.1 vs. 11.2±18.6 days, p=0.127). The rate of obtaining consent for the LST plan tended to increase after the Act (139/183 [76.0%] vs. 27/44 [61.4%], p=0.077). Notably, none of the patients made an LST decision independently. Ventilator withdrawal was more frequently performed after the Act than before (52/183 [28.4%] vs. 0/44 [0%], p<0.001). Conversely, the rate of organ donation decreased after the Act was implemented (5/183 [2.7%] vs. 6/44 [13.6%], p=0.008). Refusal to undergo surgery was more common after the Act was implemented than before (87/149 [58.4%] vs. 15/41 [36.6%], p=0.021) among the 190 patients who required surgery. CONCLUSION: After the Act on LST decisions was implemented, the rate of LST withdrawal increased in patients with acute cerebrovascular disease. However, the decision to withdraw LST was made by the patient's family rather than the patient themselves. After the execution of the Act, we also observed an increased rate of refusal to undergo surgery and a decreased rate of organ donation. The Act on LST decisions may reduce unnecessary treatments that prolong end-of-life processes without a curative effect. However, the widespread application of this law may also reduce beneficial treatments and contribute to a decline in organ donation.

Brain Invasion and Trends in Molecular Research on Meningioma.

Meningiomas are the most common primary brain tumors in adults. The treatment of non-benign meningiomas remains a challenging task, and after the publication of the 2021 World Health Organization classification, the importance of molecular biological classification is emerging. In this article, we introduce the mechanisms of brain invasion in atypical meningioma and review the genetic factors involved along with epigenetic regulation. First, it is important to understand the three major steps for brain invasion of meningeal cells: 1) degradation of extracellular matrix by proteases, 2) promotion of tumor cell migration to resident cells by adhesion molecules, and 3) neovascularization and supporting cells by growth factors. Second, the genomic landscape of meningiomas should be analyzed by major categories, such as germline mutations in NF2 and somatic mutations in non-NF2 genes (TRAF7, KLF4, AKT1, SMO, and POLR2A). Finally, epigenetic alterations in meningiomas are being studied, with a focus on DNA methylation, histone modification, and RNA interference. Increasing knowledge of the molecular landscape of meningiomas has allowed the identification of prognostic and predictive markers that can guide therapeutic decision-making processes and the timing of follow-up.

Clinical Application of the Association between Genetic Alteration and Intraoperative Fluorescence Activity of 5-Aminolevulinic Acid during the Resection of Brain Metastasis of Lung Adenocarcinoma.

The primary objective of this study was to investigate the association of certain genetic alterations and intraoperative fluorescent activity of 5-aminolevulinic acid (ALA) in brain metastasis (BM) of lung adenocarcinoma. A retrospective cohort study was conducted among 72 patients who underwent surgical resection of BM of lung adenocarcinoma at our institute for five years. Cancer cell infiltration was estimated by the intraoperative fluorescent activity of 5-ALA, and genetic alterations were analyzed by next-generation sequencing (NGS). The sensitivity and specificity for detecting cancer cell infiltration using 5-ALA were 87.5% and 96.4%, respectively. Genes associated with cell cycle regulation (p = 0.003) and cell proliferation (p = 0.044) were significantly associated with positive fluorescence activity of 5-ALA in the adjacent brain tissue. Genetic alterations in cell cycle regulation and cell proliferation were also associated with shorter recurrence-free survival (p = 0.013 and p = 0.042, respectively) and overall survival (p = 0.026 and p = 0.042, respectively) in the multivariate analysis. The results suggest that genetic alterations in cell cycle regulation and cell proliferation are associated with positive fluorescence activity of 5-ALA in the adjacent infiltrative brain tissue and influence the clinical outcome of BM of lung adenocarcinoma.

Role of Neurosurgeons in the Treatment of Acute Ischemic Stroke in the Emergency Room.

OBJECTIVE: With the recent increase in mechanical thrombectomy (MT) for acute ischemic stroke (AIS), the role of neurosurgeons in AIS treatment has become increasingly important. This study aimed to assess the outcomes of patients with AIS treated by neurosurgeons and neurologists in the emergency room (ER) of a tertiary hospital in South Korea. METHODS: From January 2020 to June 2021, 536 patients with AIS within 24 hours of symptom onset were admitted to our hospital via the ER. Based on the type of doctors who provided initial care for AIS in the ER, patients were divided into two groups : (a) neurosurgeon group (n=119, 22.2%) and (b) neurologist group (n=417, 77.8%). RESULTS: Intravenous tissue plasminogen activator (tPA) was administered in 82 (15.3%) of 536 patients (n=17 [14.3%] in the neurosurgeon group and n=65 [15.6%] in the neurologist group). The door-to-tPA time was not significantly different between both groups (median, 53 minutes; interquartile range [IQR], 45-58 vs. median, 54 minutes; IQR, 46-74; p=0.372). MT was performed in 69 patients (12.9%) (n=25, 36.2% in the neurosurgeon group and n=44, 63.8% in the neurologist group). The neurosurgeon group achieved a shorter door-to-puncture time than the neurologist group (median, 115 minutes; IQR, 107-151 vs. median, 162 minutes; IQR, 117-189; p=0.049). Good clinical outcomes (3-month modified Rankin Scale 0-2) did not differ significantly between the two groups (96/119 [80.7%] vs. 322/417 [77.2%], p=0.454). CONCLUSION: The neurosurgeon group showed similar door-to-treatment time and clinical outcomes to the neurologist group in patients with AIS in the ER. This study suggests that neurosurgeons have comparable abilities to care for patients with AIS in the ER.

Lossless Immunocytochemistry Based on Large-Scale Porous Hydrogel Pellicle for Accurate Rare Cell Analysis.

Rare cells, such as circulating tumor cells or circulating fetal cells, provide important information for the diagnosis and prognosis of cancer and prenatal diagnosis. Since undercounting only a few cells can lead to significant misdiagnosis and incorrect decisions in subsequent treatment, it is crucial to minimize cell loss, particularly for rare cells. Moreover, the morphological and genetic information on cells should be preserved as intact as possible for downstream analysis. The conventional immunocytochemistry (ICC), however, fails to meet these requirements, causing unexpected cell loss and deformation of the cell organelles which may mislead the classification of benign and malignant cells. In this study, a novel ICC technique for preparing lossless cellular specimens was developed to improve the diagnostic accuracy of rare cell analysis and analyze intact cellular morphology. To this end, a robust and reproducible porous hydrogel pellicle was developed. This hydrogel encapsulates cells to minimize cell loss from the repeated exchange of reagents and prevent cell deformation. The soft hydrogel pellicle allows stable and intact cell picking for further downstream analysis, which is difficult with conventional ICC methods that permanently immobilize cells. The lossless ICC platform will pave the way for robust and precise rare cell analysis toward clinical practice.

Impact on Endovascular Thrombectomy for Acute Ischemic Stroke of Aortic Arch Calcification on Chest X-ray.

BACKGROUND: Vascular conditions can affect the recanalization rates after endovascular thrombectomy (EVT) for acute ischemic stroke (AIS). Chest radiography can assess the conditions of the aortic arch based on the presence or absence of aortic arch calcification (AoAC). The aim of this study was to investigate the relationship between AoAC on chest radiography and first-pass successful recanalization (modified thrombolysis in cerebral infarction 2b/3 after the first-pass). METHODS: We compared the rate of first-pass successful recanalization between patients with and without AoAC. A total of 193 patients with anterior circulation occlusion who underwent EVT between January 2017 and December 2021 were included. RESULTS: AoAC was observed in 80 (41.5%) patients. Patients with AoAC were older (74.5 ± 7.78 vs. 63.9 ± 12.4 years, p < 0.001), had more EVT attempts (3.04 ± 1.95 vs. 2.01 ± 1.34 times, p < 0.001), and a longer procedural time (71.7 ± 31.2 vs. 48.7 ± 23.1 min, p < 0.001) than those without AoAC. Moreover, Patients with AoAC showed a lower incidence of first-pass successful recanalization (18.8% vs. 47.8%, p < 0.001) and a higher incidence of postprocedural hemorrhage (45.0% vs. 27.7%, p = 0.015) than those without AoAC. On multivariate analysis, AoAC was independently associated with first-pass successful recanalization (odds ratio: 0.239 [0.121-0.475], p < 0.001). CONCLUSIONS: AoAC on chest radiography can be used as a preoperative predictor of successful first-pass recanalization in patients undergoing EVT for AIS.

Dosimetric comparison between RapidArc and HyperArc in hippocampal-sparing whole-brain radiotherapy with a simultaneous integrated boost.

The HyperArc technique is known for generating high-quality radiosurgical treatment plans for intracranial lesions or hippocampal-sparing whole-brain radiotherapy (WBRT). However, there is no reported feasibility of using the HyperArc technique in hippocampal-sparing WBRT with a simultaneous integrated boost (SIB). This study aimed to compare dosimetric parameters of 2 commercially-available volumetric-modulated arc radiotherapy techniques, HyperArc and RapidArc, when using hippocampal-sparing WBRT with a SIB to treat brain metastases. Treatment plans using HyperArc and RapidArc techniques were generated retrospectively for 19 previously treated patients (1 to 3 brain metastases). The planning target volumes for the whole brain (excluding the hippocampal avoidance region; PTVWB) and metastases (PTVmet) were prescribed 25 and 45 Gy, respectively, in 10 fractions. Each plan included homogeneous and inhomogeneous delivery to the PTVmet. Dosimetric parameters for the target (conformity index [CI], homogeneity index [HI], target coverage [D95%]), and nontarget organs at risk were compared for the HyperArc and RapidArc plans. For homogeneous delivery, dosimetric parameters, including mean CI, HI, and target coverage in PTVWB and PTVmet, were superior for HyperArc than RapidArc plans (all p < 0.01). The PTVWB and PTVmet target coverage for HyperArc plans was significantly greater than for RapidArc plans (96.17% vs 93.38%, p < 0.01; 94.02% vs 92.21%, p < 0.01, respectively). HyperArc plans had significantly lower mean hippocampal Dmax and Dmin values than RapidArc plans (Dmax: 15.53 Gy vs, 16.71 Gy, p < 0.01; Dmin: 8.33 Gy vs 8.93 Gy, p < 0.01, respectively). Similarly, inhomogeneous delivery of hyperArc produced a superior target and lower hippocampal dosimetric parameters than RapidArc, except for the HI of PTVmet (all p < 0.01). HyperArc generated superior conformity and target coverage with lower hippocampal doses than RapidArc. HyperArc could be an attractive technique for hippocampal-sparing WBRT with an SIB.

The Overview of Practical Guidelines for Gliomas by KSNO, NCCN, and EANO.

Gliomas have been histologically diagnosed as the third most common primary tumor of the central nervous system (CNS) in a relatively small portion of Korea. Despite the rarity of gliomas, the disease entity is very dynamic due to its various molecular characteristics, compared with other CNS tumors. The practice of managing glioma patients is not globally established as a precise standard guideline because of the different socio-medical environments of individual countries. The Korean Society for Neuro-Oncology (KSNO) published guidelines for managing adult glioma in 2019, and the National Comprehensive Cancer Network and European Association of Neuro-Oncology published guidelines in September 2021 and March 2021, respectively. However, these guidelines have several different recommendations in practice, including tissue management, adjuvant treatment after surgical resection, and salvage treatment for recurrent/progressive gliomas. Currently, the KSNO guideline working group is preparing an updated version of the guideline for managing adult gliomas. In this review, common features have been verified and different points are analyzed. Consequently, this review is expected to be informative and helpful to provide high quality evidence and a strong recommendation level for the establishment of new KSNO guidelines for managing gliomas.

Effect of Antiplatelet Preparation Before Endovascular Thrombectomy for Cerebral Infarction on Procedural Thromboembolism.

AIM: To compare an antiplatelet-preparation group with a no-preparation group to evaluate the effect of the antiplatelet preparation on procedural thromboembolism during endovascular thrombectomy (EVT) with diffusion-weighted imaging (DWI), retrospectively. MATERIAL AND METHODS: From January 2017 to April 2020, EVT was performed in 60 patients with cerebral infarction. Patients were categorized into the antiplatelet-preparation group (n=25) or the no-preparation group (n=35). Procedural thromboembolism was defined as new DWI-positive lesions in other areas of the occluded artery after EVT. RESULTS: The antiplatelet-preparation and no-preparation groups did not differ in the rate of procedural thromboembolism occurrence (6/25 [24.0%] vs. 6/35 [17.1%]; p=0.532). Procedural thromboembolism was associated with age (74.4 ± 6.95 years vs. 65.7 ± 12.9 years; p=0.028), atherosclerotic occlusion (66.7% vs. 29.2%; p=0.022), and procedural time (97.4 ± 45.7 min vs. 60.1 ± 28.8 min; p=0.001). Multivariable logistic regression analysis showed that factors affecting procedural thromboembolism during EVT for cerebral infarction were old age (odds ratio [OR], 1.133; 95% confidence interval [CI], 1.009-1.273; p=0.035), atherosclerotic occlusion (OR, 7.434; 95% CI, 1.272-43.431; p=0.026), and longer procedural time (OR, 1.023; 95% CI, 1.001 - 1.046; p=0.006). CONCLUSION: The antiplatelet preparation had no significant protective effect on procedural thromboembolism during EVT for cerebral infarction. Old age, atherosclerotic occlusion, and longer procedural time were independent risk factors for procedural thromboembolism during EVT for cerebral infarction.