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.

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.

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.

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.

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.

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.

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.

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.

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.

EPCO-42. HYPO-TRIMETHYLATION OF HISTONE H3 LYSINE 4 AND HYPER-DI/TRIMETHYLATION OF HISTONE H3 LYSINE 27 AS THE EPIGENETIC MARKERS OF POOR PROGNOSIS FOR PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA PATIENTS

PURPOSE

This study aimed to investigate the methylation status of major histone modification sites in PCNSL samples and examine their prognostic role in PCNSL patients.

METHODS

Between 2007 and 2020, 87 patients were histopathologically diagnosed as PCNSL, and they were treated with same protocol of high-dose methotrexate-based combination chemotherapy. Clinical data for PFS and OS was obtained from medical records retrospectively. Immunohistochemical staining for FFPE samples of PCNSL from pathological archives in our institute was performed for major histone modification site such as histone H3K4, H3K9, H3K27, H3K14, and H3K36. After detection of meaningful methylation site, we examine the histone modification enzyme which induce methylation or demethylation on each site using immunohistochemical staining. The meaningful immunoreactivity was validated with qRT-PCR and western blotting using fresh tissue of PCNSL under refrigerated state in N2O container.

RESULTS

Among 87 patients, 28 patients (32.2%) experienced recurrence or progression and 11 patients (12.6%) succumbed their disease during follow-up for 12 months or more. More frequent recurrences was found in hypomethylation of H3K4me3 (p=0.004), and hypermethylation of H3K27me2 (p&lt; 0.001) and H3K27me3 (p=0.002). These factors were also statistically related with short PFS and OS in univariate and multivariate analysis. At the next step, histone modification enzyme inducing demethylation of H3K4 (LSD1/2, KDM5A-D, NO66), and methylation of H3K27 (EZH1/2) was immunohistochemically stained. Among them, the immunoreactivity of KDM5A was reversely associated with methylation status of H3K4me3 (R2=-1.243), and immunoreactivity of EZH2 was directly associated with methylation status of H3K27me2 (R2=0.988) and H3K27me3 (R2=1.139). These results was confirmed using RT-PCR and western blotting in fresh sample of PCNSL.

CONCLUSION

Our presenting study suggest that hypomethylation of H3K4me3, and hypermethylation of H3K27me2 and H3K27me3 could be associated with poor outcome of PCNSL patients. These relationship was modified by KDM5A as H3K4 demethylase and EZH2 as H3K27 methyltransferase.

Diffusion-weighted imaging-positive lesions following endovascular treatment for ruptured and unruptured aneurysms: Its incidence according to antithrombotic drugs

Objective

Microembolic infarcts are frequently observed on diffusion-weighted imaging (DWI) following endovascular treatment. We investigated DWI-positive lesions and symptomatic ischemic complications (SICs) in patients with ruptured and unruptured aneurysms following coiling and the relationship between DWI-positive lesions and antithrombotic drugs.

Methods

Between January 2016 and December 2020, 83 patients underwent DWI within 48 h following endovascular treatment for ruptured (n=30) and unruptured (n=53) aneurysms.

Results

The overall rate of DWI-positive lesions was 55.4%. There were no significant differences in the occurrence rate (45.3% vs. 43.3%, p=1.000) and the number of lesions (2.7±4.6 vs. 4.0±5.3, p=0.237) between unruptured and ruptured aneurysms. SIC occurred more frequently in patients with ruptured aneurysms than unruptured ones (20.0% vs. 1.9%, p=0.015). The cutoff value of DWI-positive lesions for predicting SIC was 5 (sensitivity 100%, specificity 78.9%). The procedure time was significantly longer in patients with DWI-positive lesions ≥5 than those with DWI-positive lesions <5 (104.1±43.8 vs. 85.1±30.8 min, p=0.030). Patients with DWI-positive lesions <5 were more frequently observed in the postprocedural heparinization group than in the no heparinization group (85.7% vs. 58.5%, p=0.012).

Conclusions

The incidence of DWI-positive lesions did not differ significantly between the ruptured and unruptured aneurysms. However, SIC occurred more frequently in patients with ruptured aneurysms. Longer procedure time is a risk factor for DWI-positive lesions, and postprocedural heparinization seems to reduce the incidence of DWI-positive lesions.

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.

Ki67 index is the most powerful factor for predicting the recurrence in atypical meningioma: Retrospective analysis of 99 patients in two institutes

Objective

The primary objective of this study was to identify predicting factors for local control (LC) of atypical meningioma, and we validated them with comparing the predicting factors for recurrence-free survival (RFS). We also examined the rate of LC after surgical resection with or without adjuvant treatment and RFS.

Methods

Clinical and radiological records of patients with atypical meningiomas diagnosed at two institutes from January 2000 to December 2018 were reviewed retrospectively. Histopathological features were also reviewed using formalin-fixed paraffin embedded samples from pathological archives.

Results

Of the 99 atypical meningiomas eligible for analysis, 36 (36.4%) recurred during the follow-up period (mean, 83.3 months; range, 12–232 months). The rate of 3-year LC and 5-year LC was 80.8% and 74.7%, respectively. The mean time-to-recurrence was 49.4 months (range, 12–150). The mean RFS was 149.3 months (95% confidence interval, 128.8–169.8 months) during the mean follow-up duration of 83.3 months (range, 12–232 months). Multivariate analysis using Cox proportional-hazard regression model showed that the extent of resection (hazard ratio [HR], 4.761; p=0.013), Ki67 index (HR, 8.541; p=0.004), mitotic index (HR, 3.275; p=0.044), and tumor size (HR, 3.228; p=0.041) were independently associated with LC. These factors were also statistically associated with RFS. In terms of radiotherapy after surgical resection, the recurrence was not prevented by immediate radiotherapy because of the strong effect of proliferative index on recurrence.

Conclusion

The present study suggests that the extent of resection, proliferative index (according to Ki67 expression) and mitotic index, and tumor size are associated with recurrence of atypical meningiomas. However, our results should be further validated through prospective and randomized clinical trials to overcome the inborn bias of retrospective nature of the study design.

Impact of the Coronavirus Disease Pandemic on Patients with Head Injuries in South Korea

Objective

The coronavirus disease 2019 (COVID-19) pandemic is affecting the characteristics of patients with head injuries. This study aimed to evaluate the effect of the COVID-19 pandemic on patients with head injuries at a regional emergency medical center in South Korea.

Methods

From April 2019 to November 2020, 350 patients with head injuries were admitted to our hospital. The study period was divided into the pre-COVID-19 (n=169) and COVID-19 (n=181) eras (10 months each). Patients with severe head injuries requiring surgery (n=74) were categorized into those who underwent surgery (n=41) and those who refused surgery (n=33).

Results

Head injuries in pediatric patients (<3 years) were more frequent in the COVID-19 era than in the pre-COVID-19 era (8.8% vs. 3.6%, p=0.048). More patients refused surgery in the COVID-19 era than in the pre-COVID-19 era (57.9% vs. 30.6%, p=0.021). Refusal of surgery was associated with old age (67.7±14.5 vs. 52.4±19.1, p<0.001), marital status (married, 84.8% vs. 61.0%, p=0.037), unemployment (42.4% vs. 68.3%, p=0.034), COVID-19 era (66.7% vs. 39.0%, p=0.021), and lower Glasgow coma scale scores (6.12±3.08 vs. 10.6±3.80, p<0.001). Multivariable logistic regression analysis revealed that refusal of surgery was independently associated with old age (adjusted odds ratio [OR], 1.084; 95% confidence interval [CI], 1.030–1.140; p=0.002), COVID-19 era (adjusted OR, 6.869; 95% CI, 1.624–29.054; p=0.009), and lower Glasgow coma scale scores (adjusted OR, 0.694; 95% CI, 0.568–0.848; p<0.001).

Conclusion

We observed an increased prevalence of head injuries in pediatric patients (<3 years) during the COVID-19 pandemic. Additionally, among patients with severe head injuries requiring surgery, more patients refused to undergo surgery during the COVID-19 pandemic.

Continuous centrifugal microfluidics (CCM) isolates heterogeneous circulating tumor cells via full automation

Understanding cancer heterogeneity is essential to finding diverse genetic mutations in metastatic cancers. Thus, it is critical to isolate all types of CTCs to identify accurate cancer information from patients. Moreover, full automation robustly capturing the full spectrum of CTCs is an urgent need for CTC diagnosis to be routine clinical practice.

Methods: Here we report the full capture of heterogeneous CTC populations using fully automated, negative depletion-based continuous centrifugal microfluidics (CCM).

Results: The CCM system demonstrated high performance (recovery rates exceeding 90% and WBC depletion rate of 99.9%) across a wide range of phenotypes (EpCAM(+), EpCAM(-), small-, large-sized, and cluster) and cancers (lung, breast, and bladder). Applied in 30 lung adenocarcinoma patients harboring epidermal growth factor receptor (EGFR) mutations, the system isolated diverse phenotypes of CTCs in marker expression and size, implying the importance of unbiased isolation. Genetic analyses of intra-patient samples comparing cell-free DNA with CCM-isolated CTCs yielded perfect concordance, and CTC enumeration using our technique was correlated with clinical progression as well as response to EGFR inhibitors.

Conclusion: Our system also introduces technical advances which assure rapid, reliable, and reproducible results, thus enabling a more comprehensive application of robust CTC analysis in clinical practice.

Hypo-trimethylation of Histone H3 Lysine 4 and Hyper-tri/dimethylation of Histone H3 Lysine 27 as Epigenetic Markers of Poor Prognosis in Patients with Primary Central Nervous System Lymphoma

Purpose

This study aimed to investigate the methylation status of major histone modification sites in primary central nervous system lymphoma (PCNSL) samples and examine their prognostic roles in patients with PCNSL.

Materials and Method

Between 2007 and 2020, 87 patients were histopathologically diagnosed with PCNSL. We performed immunohistochemical staining of the formalin-fixed paraffin-embedded samples of PCNSL for major histone modification sites, such as H3K4, H3K9, H3K27, H3K14, and H3K36. After detection of meaningful methylation sites, we examined histone modification enzymes that induce methylation or demethylation at each site using immunohistochemical staining. The meaningful immunoreactivity was validated by western blotting using fresh tissue of PCNSL.

Results

More frequent recurrences were found in hypomethylation of H3K4me3 (p=0.004) and hypermethylation of H3K27me2 (p<0.001) and H3K27me3 (p=0.002). These factors were also statistically related to short PFS and OS in the univariate and multivariate analyses. Next, histone modification enzymes inducing the demethylation of H3K4 (lysine-specific demethylase (LSD)-1/2 and Jumonji AT-rich interactive domain 1A (JARID1A-D)) and methylation of H3K27 (enhancer of zeste homolog (EZH)-1/2) were immunohistochemically stained. Among them, the immunoreactivity of JARID1A inversely associated with the methylation status of H3K4me3 (R2=-1.431), and immunoreactivity of EZH2 was directly associated with the methylation status of H3K27me2 (R2=0.667) and H3K27me3 (R2=0.604). These results were validated by western blotting in fresh PCNSL samples.

Conclusion

Our study suggests that hypomethylation of H3K4me3 and hypermethylation of H3K27me2 and H3K27me3 could be associated with poor outcomes in patients with PCNSL and that these relationships are modified by JARID1A and EZH2.

Clinical Outcomes of RTOG 9310 Protocol for Primary Central Nervous System Lymphoma: Single-Center Experience with 87 Patients

The Radiation Therapy Oncology Group (RTOG) 9310 protocol clinical trial established high-dose methotrexate (HDMTX) as the standard for primary central nervous system lymphoma (PCNSL). We aimed to investigate the RTOG 9310 protocol’s PCNSL outcomes by examining progression-free survival (PFS) and overall survival (OS) rates and determining the influential factors. Between 2007 and 2020, 87 patients were histopathologically diagnosed with PCNSL and treated with the RTOG 9310 protocol. All received HDMTX 2.5 g/m² and vincristine 1.4 mg/m²/day for 1 day during weeks 1, 3, 5, 7, and 9, and procarbazine 100 mg/m²/day for 1 day during weeks 1, 5, and 9. Dexamethasone was administered on a standard tapering schedule from the first week to the sixth week. Whole brain radiotherapy (WBRT), consisting of 45 Gy for patients with less than a complete response to the chemotherapy or 36 Gy for complete responders, was started 1 week after the last dose of chemotherapy was administered. Within three weeks of the completion of WBRT, patients received two courses of cytarabine, which were separated by 3–4 weeks. Clinical, radiological, and histopathological characteristics were retrospectively reviewed. All patients completed five HDMTX cycles and a mean follow-up of 60.2 (range, 6–150) months. Twenty-eight (32.2%) patients experienced recurrence during follow-up. The mean time to recurrence was 21.8 months, while the mean PFS was 104.3 (95% confidence interval (CI), 90.6–118.0) months. Eleven (12.6%) patients died; the mean OS was 132.1 (95% CI, 122.2–141.9) months. The 3- and 5-year survival rates were 92.0% and 87.4%, respectively. One patient experienced acute renal failure, while the remainder tolerated any cytotoxic side effects. On multivariate analysis, the Eastern Cooperative Oncology Group performance score ≤ 2; the International Extranodal Lymphoma Study Group low-risk status; XBP-1, p53, and c-Myc negativity; homogenous enhancement; gross total resection, independently correlated with long PFS and OS. The RTOG 9310 protocol is effective for PCNSL and features good outcomes.

ECOA-3. MLL4, UTX, and EZH2 regulate the expression of transcription factors associated with the epithelial-to-mesenchymal transition of lung cancer during metastasis to the brain at posttranscriptional steps

Purpose

The objective of this study was to investigate the epigenetic role of histone lysine methylation/demethylation on the expression of epithelial-to-mesenchymal transition (EMT) associated transcriptional factors (TFs) during the metastasis of lung adenocarcinoma to the brain.

Methods

Paired samples of lung adenocarcinoma and brain metastasis (BM) were analyzed in 46 individual patients. Both samples were obtained by surgical resection or biopsy of the lung and brain. The paraffin-fixed formalin-embedded samples were obtained from the pathology archives in our institute. In samples of lung adenocarcinoma and BM, immunohistochemical staining was performed for epithelial markers, mesenchymal markers, EMT-TFs, histone lysine methyltransferase and demethylase. And the verification of the present result was performed by qRT-PCR.

Results

The immunoreactivity of EMT-TFs such as Slug (15.6% vs. 42.6%, p = 0.005), Twist (23.6% vs. 45.9%, p = 0.010) and ZEB1 (15.0% vs. 55.9%, p = 0.002) was increased in BM compared with that in lung adenocarcinoma. Epigenetic inducers such as H3K4 methyltransferase (MLL4, p = 0.018) and H3K36me3 demethylase (UTX, p = 0.003) were statistically increased, and epigenetic repressors such as EZH2 (H3K27 methyltransferase, p = 0.046) were significantly decreased in BM compared with those in lung adenocarcinoma. The expression of UTX-ZEB1 (R2 linear = 1.204) and MLL4-Slug (R2 linear = 0.987) was increased in direct proportion, and EZH2-Twist (R2 linear = - 2.723) decreased in reverse proportion. The qRT-PCR showed the same results.

Conclusion

The results suggest that certain histone lysine methyltransferase/demethylase, such as MLL4, UTX, and EZH2, regulate the expression of EMT-TFs such as Slug, ZEB1, and Twist epigenetically, which may thereby influence cancer metastasis from the lung to the brain.

Improving Door-To-Puncture Time in Mechanical Thrombectomy with Direct Care from a Neurointerventionalist in the Emergency Department

OBJECTIVE

A shorter door-to-puncture time is an independent predictor of good clinical outcomes in patients with acute ischemic stroke (AIS) who undergo mechanical thrombectomy (MT). We recently initiated a protocol for direct care from neurointerventionalists (NIs) in the emergency department (ED) rather than from non-NI neurologists for patients with AIS. Our aim was to investigate whether NIs, as the first point-of-care physicians for stroke in the ED, could shorten door-to-puncture time compared to non-NI neurologists.

METHODS

From January 2020 to December 2020, 50 patients with AIS underwent MT at our hospital. Patients were divided into 2 groups based on the type of physician who provided initial care for stroke in the ED: (a) NI group (n = 20) and (b) non-NI group (n = 30). The door-to-puncture time was retrospectively analyzed.

RESULTS

The NI group had a significantly shorter door-to-puncture time than the non-NI group (135.2 ± 50.0 minutes vs. 167.2 ± 54.3 minutes, P = 0.040). A door-to-puncture time of ≤120 minutes was more frequently achieved in the NI group than in the non-NI group (55.0% vs. 23.3%, P = 0.022). Multivariable logistic regression analysis revealed that a door-to-puncture time of ≤120 minutes was independently associated with the NI group (adjusted odds ratio 4.098, 95% confidence interval 1.085-15.479, P = 0.037).

CONCLUSIONS

Our study showed that NIs, as the first point-of-care stroke physicians in the ED, were associated with shorter door-to-puncture times. We suggest that NIs should be at the forefront of care for patients with AIS in the acute setting by performing triage and deciding on and performing MT.

The Korean Society for Neuro-Oncology (KSNO) Guideline for Adult Diffuse Midline Glioma: Version 2021.1

BACKGROUND

There have been no guidelines for the management of adult patients with diffuse midline glioma (DMG), H3K27M-mutant in Korea since the 2016 revised WHO classification newly defined this disease entity. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, had begun preparing guidelines for DMG since 2019.

METHODS

The Working Group was composed of 27 multidisciplinary medical experts in Korea. References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of keywords. As 'diffuse midline glioma' was recently defined, and there was no international guideline, trials and guidelines of 'diffuse intrinsic pontine glioma' or 'brain stem glioma' were thoroughly reviewed first.

RESULTS

The core contents are as follows. The DMG can be diagnosed when all of the following three criteria are satisfied: the presence of the H3K27M mutation, midline location, and infiltrating feature. Without identification of H3K27M mutation by diagnostic biopsy, DMG cannot be diagnosed. For the primary treatment, maximal safe resection should be considered for tumors when feasible. Radiotherapy is the primary option for tumors in case the total resection is not possible. A total dose of 54 Gy to 60 Gy with conventional fractionation prescribed at 1-2 cm plus gross tumor volume is recommended. Although no chemotherapy has proven to be effective in DMG, concurrent chemoradiotherapy (± maintenance chemotherapy) with temozolomide following WHO grade IV glioblastoma's protocol is recommended.

CONCLUSION

The detection of H3K27M mutation is the most important diagnostic criteria for DMG. Combination of surgery (if amenable to surgery), radiotherapy, and chemotherapy based on comprehensive multidisciplinary discussion can be considered as the treatment options for DMG.

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.

The Korean Society for Neuro-Oncology (KSNO) Guideline for Antiepileptic Drug Usage of Brain Tumor: Version 2021.1

Background

To date, there has been no practical guidelines for the prescription of antiepileptic drugs (AEDs) in brain tumor patients in Korea. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, had begun preparing guidelines for AED usage in brain tumors since 2019.

Methods

The Working Group was composed of 27 multidisciplinary medical experts in Korea. References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of the keywords.

Results

The core contents are as follows. Prophylactic AED administration is not recommended in newly diagnosed brain tumor patients without previous seizure history. When AEDs are administered during peri/postoperative period, it may be tapered off according to the following recommendations. In seizure-naïve patients with no postoperative seizure, it is recommended to stop or reduce AED 1 week after surgery. In seizure-naïve patients with one early postoperative seizure (<1 week after surgery), it is advisable to maintain AED for at least 3 months before tapering. In seizure-naïve patients with ≥2 postoperative seizures or in patients with preoperative seizure history, it is recommended to maintain AEDs for more than 1 year. The possibility of drug interactions should be considered when selecting AEDs in brain tumor patients. Driving can be allowed in brain tumor patients when proven to be seizure-free for more than 1 year.

Conclusion

The KSNO suggests prescribing AEDs in patients with brain tumor based on the current guideline. This guideline will contribute to spreading evidence-based prescription of AEDs in brain tumor patients in Korea.

SURG-29. CLINICAL FACTORS ASSOCIATED WITH RECURRENCE IN ATYPICAL MENINGIOMA: RETROSPECTIVE ANALYSIS OF 99 PATIENTS IN TWO INSTITUTES

OBJECTIVE

The objectives of this study were to examine the local control (LC) rate of atypical meningioma after surgical resection with or without adjuvant treatment, to identify risk factors for the recurrence of atypical meningioma, and to compare our results to known factors from the literature.

METHODS

Clinical and radiological records of patients with atypical meningiomas diagnosed at two institutes from January 2000 to December 2018 were reviewed retrospectively. Histopathological features were also reviewed using formalin-fixed paraffin embedded samples from pathological archives.

RESULTS

Of the 99 atypical meningiomas eligible for analysis, 36 (36.4%) recurred during the follow-up period (mean 83.3 months, range 12–232 months). The rate of 3-year LC and 5-year LC was 80.8% and 74.7% respectively. The mean time-to-recurrence was 49.4 months (range 12–150 months). Multivariate analysis using Cox proportional-hazard regression model showed that the extent of resection (Hazard ratio [HR] 4.761, p=0.013), Ki67 index (HR 8.541, p=0.004), mitotic index (HR 3.275, p=0.044), tumor size (HR 3.228, p=0.041), and radiotherapy (HR 3.816, p=0.029) were independently associated with 3-year LC. These factors was also statistically associated with recurrence-free survival. In terms of radiotherapy after surgical resection, the recurrence was not prevented by immediate radiotherapy because of the strong effect of proliferative index on recurrence. Three cases of malignant transformation to WHO grade III meningioma were histopathologically confirmed after repeated surgery. Two out of these three patients succumbed to malignant transformation. The mean Ki67 proliferative index increased for recurrent cases in 18 patients (58.1%) from 7.55% (range 4-16) to 11.81% (range 5-24).

CONCLUSION

The present study suggests that the extent of resection, proliferative index (according to Ki67 expression) and mitotic index, tumor size, and radiotherapy are associated with recurrence of atypical meningiomas. However, our results should be further validated through prospective and randomized clinical trials.

RADT-35. POSTOPERATIVE RADIOTHERAPY FOR WHO GRADE II–III INTRACRANIAL EPENDYMOMA IN ADULTS: AN INTERGROUP COLLABORATIVE STUDY (KROG 18-06/KNOG 18-01)

BACKGROUND

To evaluate the impact of adjuvant postoperative radiotherapy (PORT) in adult WHO grade II–III intracranial ependymoma (IEPN).

METHODS

A total of 172 pathologically confirmed adult grade II–III IEPN patients from 12 institutions were eligible. Of them, 106 (61.6%) and 66 (38.4%) patients were grade II and III, respectively. For grade II and III IEPNs, 51 (48.1%) and 59 (89.4%) patients received PORT, respectively. The median dose to the primary tumor bed was 54.0 Gy and 59.4 Gy for grade II and III patients, respectively. The prognostic impact of sex, age, performance, WHO grade, location, size, surgical extent, and PORT on local control (LC), progression-free survival (PFS), and overall survival (OS) were evaluated by univariate and multivariate analysis.

RESULTS

The median follow-up period for survivors was 88.1 months. The 5-/10-year LC, PFS, and OS rates were 64.8%/54.0%, 56.4%/44.8%, and 76.6%/71.0%, respectively. On multivariate analysis, adjuvant PORT significantly improved LC (P=0.002), PFS (P=0.002), and OS (P=0.043). Older age (P&lt; 0.001), WHO grade III (P&lt; 0.001), larger tumor size (P=0.004), and lesser surgical extent (P&lt; 0.001) were also negative factors for OS. Adjuvant PORT also improved LC (P=0.010), PFS (P=0.007), and OS (P=0.069) on multivariate analysis for grade II IEPNs.

CONCLUSION

This multicenter retrospective study supports the role of adjuvant PORT in terms of disease control and survival in adult grade II–III IEPNs. Prospective randomized trials focused on individualized treatment based on molecular subtypes is warranted.

Postoperative radiotherapy for WHO grade II-III intracranial ependymoma in adults: An intergroup collaborative study (KROG 18-06/KNOG 18-01)

BACKGROUND AND PURPOSE

To evaluate the impact of adjuvant postoperative radiotherapy (PORT) in adult WHO grade II-III intracranial ependymoma (IEPN).

MATERIALS AND METHODS

A total of 172 pathologically confirmed adult grade II-III IEPN patients from 12 institutions were eligible. Of them, 106 (61.6%) and 66 (38.4%) patients were grade II and III, respectively. For grade II and III IEPNs, 51 (48.1%) and 59 (89.4%) patients received PORT, respectively. The median dose to the primary tumor bed was 54.0 Gy and 59.4 Gy for grade II and III patients, respectively. The prognostic impact of sex, age, performance, WHO grade, location, size, surgical extent, and PORT on local control (LC), progression-free survival (PFS), and overall survival (OS) were evaluated by univariate and multivariate analysis.

RESULTS

The median follow-up period for survivors was 88.1 months. The 5-/10-year LC, PFS, and OS rates were 64.8%/54.0%, 56.4%/44.8%, and 76.6%/71.0%, respectively. On multivariate analysis, adjuvant PORT significantly improved LC (P = 0.002), PFS (P = 0.002), and OS (P = 0.043). Older age (P < 0.001), WHO grade III (P < 0.001), larger tumor size (P = 0.004), and lesser surgical extent (P < 0.001) were also negative factors for OS. Adjuvant PORT also improved LC (P = 0.010), PFS (P = 0.007), and OS (P = 0.069) on multivariate analysis for grade II IEPNs.

CONCLUSION

This multicenter retrospective study supports the role of adjuvant PORT in terms of disease control and survival in adult grade II-III IEPNs. Prospective randomized trials focused on individualized treatment based on molecular subtypes is warranted.

A National Consensus Survey for Current Practice in Brain Tumor Management I: Antiepileptic Drug and Steroid Usage

BACKGROUND

The Guideline Working Group of the Korean Society for Neuro-Oncology (KSNO) conducted a nationwide questionnaire survey for diverse queries faced in the treatment of brain tumors. As part I of the survey, the aim of this study is to evaluate national patterns of clinical practice about antiepileptic drug (AED) and steroid usage for management of brain tumors.

METHODS

A web-based survey was sent to all members of the KSNO by email. The survey included 9 questions of AED usage and 5 questions of steroid usage for brain tumor patients. All questions were developed by consensus of the Guideline Working Group.

RESULTS

The overall response rate was 12.8% (54/423). Regarding AED usage, the majority of respondents (95.2%) routinely prescribed prophylactic AEDs for patients with seizure at the peri/postoperative period. However, as many as 72.8% of respondents prescribed AED routinely for seizure-naïve patients, and others prescribed AED as the case may be. The duration of AED prophylaxis showed wide variance according to the epilepsy status and the location of tumor. Levetiracetam (82.9%) was the most preferred AED for epilepsy prophylaxis. Regarding steroid usage, 90.5% of respondents use steroids in perioperative period, including 34.2% of them as a routine manner. Presence of peritumoral edema (90.9%) was considered as the most important factor determining steroid usage followed by degree of clinical symptoms (60.6%). More than half of respondents (51.2%) replied to discontinue the steroids within a week after surgery if there are no specific medical conditions, while 7.3% preferred slow tapering up to a month after surgery.

CONCLUSION

The survey demonstrated the prevailing practice patterns on AED and steroid usage in neuro-oncologic field among members of the KSNO. This information provides a point of reference for establishing a practical guideline in the management of brain tumor patients.

A National Consensus Survey for Current Practice in Brain Tumor Management II: Diffuse Midline Glioma and Meningioma

Background

The Guideline Working Group of the Korean Society for Neuro-Oncology (KSNO) conducted a nationwide questionnaire survey for diverse queries faced in the treatment of brain tumors. As part II of the survey, the aim of this study is to evaluate the national patterns of clinical practice for patients with diffuse midline glioma and meningioma.

Methods

A web-based survey was sent to all members of the KSNO by email. The survey included 4 questions of diffuse midline glioma and 6 questions of meningioma (including 2 case scenarios). All questions were developed by consensus of the Guideline Working Group.

Results

In the survey about diffuse midline glioma, 76% respondents performed histologic confirmation to identify H3K27M mutation on immunohistochemical staining or sequencing methods. For treatment of diffuse midline glioma, respondents preferred concurrent chemoradiotherapy with temozolomide (TMZ) and adjuvant TMZ (63.8%) than radiotherapy alone (34.0%). In the survey about meningioma, respondents prefer wait-and-see policy for the asymptomatic small meningioma without peritumoral edema. However, a greater number of respondents had chosen surgical resection as the first choice for all large size meningiomas without exception, and small size meningiomas with either peritumoral edema or eloquent location. There was no single opinion with major consensus on long-term follow-up plans for asymptomatic meningioma with observation policy. As many as 68.1% of respondents answered that they would not add any adjuvant therapies for World Health Organization grade II meningiomas if the tumor was totally resected including dura.

Conclusion

The survey demonstrates the prevailing clinical practice patterns for patients with diffuse midline glioma and meningioma among members of the KSNO. This information provides a point of reference for establishing a practical guideline in the management of diffuse midline glioma and meningioma.

A National Consensus Survey for Current Practice in Brain Tumor Management III: Brain Metastasis and Primary Central Nervous System Lymphoma

BACKGROUND

The Guideline Working Group of the Korean Society for Neuro-Oncology (KSNO) conducted the nationwide questionnaire survey for diverse queries facing to treat patients with brain tumor. As part III of the survey, the aim of this study is to evaluate the national patterns of clinical practice for patients with brain metastasis and primary central nervous system lymphoma (PCNSL).

METHODS

A web-based survey was sent to all members of the KSNO by email. The survey included 7 questions of brain metastasis and 5 questions of PCNSL, focused on the management strategies in specific situations. All questions were developed by consensus of the Guideline Working Group.

RESULTS

In the survey about brain metastasis, respondents preferred surgical resection with adjuvant treatment for patients with a surgically accessible single brain metastatic lesion less than 3 cm in size without extracranial systemic lesions. However, most respondents considered radiosurgery for surgically inaccessible lesions. As the preferred treatment of multiple brain metastases according to the number of brain lesions, respondents tended to choose radiotherapy with increasing number of lesions. Radiosurgery was mostly chosen for the brain metastases of less than or equal to 4. In the survey about PCNSL, a half of respondents choose high-dose methotrexate-based polychemotherapy as the first-line induction therapy for PCNSL. The consolidation and salvage therapy showed a little variation among respondents. For PCNSL patients with cerebrospinal fluid dissemination, intrathecal chemotherapy was most preferred.

CONCLUSION

The survey demonstrates the prevailing clinical practice patterns for patients with brain metastasis and PCNSL among members of the KSNO. This information provides a point of reference for establishing a practical guideline in the management of brain metastasis and PCNSL.

INNV-07. THE KOREAN SOCIETY FOR NEURO-ONCOLOGY (KSNO) GUIDELINE FOR GLIOMAS: VERSION 2019.01

BACKGROUND

There was no practical guideline for the management of patients with central nervous system (CNS) tumor in Korea for many years. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, started to prepare a guideline for CNS tumors from February 2018.

METHODS

The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of keywords.

RESULTS

First, for the glioblastoma as WHO Grade IV Gliomas, the maximal safe resection if feasible is recommended. Patients aged ≤ 70 years with good performance should be treated by concurrent chemoradiotherapy with temozolomide followed by adjuvant temozolomide chemotherapy (Stupp’s protocol) or standard brain radiotherapy alone. However, those with poor performance should be treated by hypofractionated brain radiotherapy (preferred) ± concurrent or adjuvant temozolomide or temozolomide alone (Level III) or supportive treatment. Second, for the WHO Grade III Gliomas, patients with anaplastic astrocytoma, IDH-mutant should be treated by standard brain radiotherapy followed by adjuvant temozolomide chemotherapy, or Stupp’s protocol, or standard brain radiotherapy with neoadjuvant or adjuvant PCV chemotherapy, or Standard brain radiotherapy alone (Level III). However, those anaplastic astrocytoma, IDH-wildtype should be treated by the protocol for glioblastoma. Third, for the WHO Grade II Gliomas, patients with diffuse astrocytoma, IDH-wildtype without molecular feature of glioblastoma should be treated by standard brain radiotherapy and adjuvant temozolomide chemotherapy (Level III), or standard brain radiotherapy alone, or observation. And patients with diffuse astrocytoma IDH-mutant and oligodendroglioma (IDH-mutant and 1p/19q codeletion) should be treated according to the risk factors.

CONCLUSION

The recent KSNO’s guideline recommends that glioma should be treated according to the molecular as well as histological features. However, the practice can be limited by the National Insurance for Health in Korea.

GENE-07. INFLUENCE OF EPIGENETIC MODULATION OF THE T-CELL REGULATORS EXPRESSION ON GLIOBLASTOMAS BY HISTONE 3 LYSINE METHYLTRANSFERASE OR DEMETHYLASE ON THE PROGNOSIS OF THE GLIOBLASTOMA PATIENTS

PURPOSE

The primary aim of this study is to investigate the expression of the T cell stimulators and inhibitors as well as histone modifying enzymes in the glioblastoma cells. Based on the expression of these proteins, authors estimate the prognostic role in glioblastoma patients and also validate the known prognostic factors.

MATERIALS AND METHODS

Using 84 FFPE samples of glioblastoma in the pathologic archives at our institute, immunohistochemical staining for T cell stimulators (CD 27, CD 28, CD 137, OX40, ICOS), inhibitors (CTLA-4, PD-1, PD-L1, TIM3, CD200R), histone 3 lysine methyltransferase (MLL4, RIZ, EZH1, NSD2), and histone 3 lysine demethylase (KDM5c, JMJD1a, UTX, JMJD5).

RESULTS

Median values of the immunohistochemical staining for T cell stimulators and inhibitors were 16.3% of CD27, 10.4% of CD28, 47.5% of CD137, 52.9% of ICOS, 32.2% of OX40, 31.4% of CTLA-4, 7.2% of PD-1, 55.5% of PD-L1, 62.2% of TIM3, and 42.8% of CD200R. In multivariate analysis, increased expression of CD28 (p=0.042), CD137 (p=0.009), EZH1 (p=0.040), and decreased expression of CTLA-4 (p=0.003), PDL-1 (p=0.020) in glioblastoma cells were independently associated with longer OS as well as known prognostic factors such as young age, high KPS, wide extent of resection, PRA class, and methylated MGMT promoter. Interestingly, 42 of 43 samples (97.7%) with decreased PDL1 expression had the increased EZH1 expression, 31 of 33 samples (93.9%) with decreased CTLA4 expression had the increased RIZ expression, 25 of 26 samples (96.2%) with increased CD137 expression had the increased UTX expression, and 36 of 39 samples (92.3%) with increased CD28 expression had the increased JMJD1a expression, respectively.

CONCLUSION

The result of presenting study suggest that the regulators of T cell can be considered as independent prognostic factors in glioblastoma patients and the expression of these regulators can be controlled by unique histone 3 lysine methylation enzymes.

Demographic and Socioeconomic Factors for Renouncing Further Active Therapy for Patients with Brain Metastasis of Non-Small Cell Lung Cancer

Background

As patients with brain metastasis (BM) of non-small cell lung cancer (NSCLC) have dismal prognosis, some of them decide to discontinue further treatment for BM. The objective of this study was to determine factors for renouncing further active therapy in patients with BM of NSCLC, focusing on their demographic and socioeconomic status.

Methods

Medical records of 105 patients with radiological diagnosis of BM of NSCLC for the recent 11 years at authors' institution were retrospectively reviewed. Clinical features as well as demographic and socioeconomic characteristics such as marriage status, cohabiting family members, religious affiliations, educational background, and economic responsibility were reviewed.

Results

Median overall survival (OS) was 13.84 (95% CI: 10.26–17.42) years in 67 patients (group A) who underwent active treatment (radiotherapy and/or chemotherapy) and 4.76 (95% CI: 3.12–6.41) years in 38 patients (group B) who renounced active treatment. Less patients were unmarried (p=0.046), more cohabitating family members (p=0.008), and economically independent (p=0.014) in group A than those in group B. Similarly, the unmarried, and none cohabitating family members had short OS (5.17 and 7.38 years, respectively). In multivariate analysis for predisposing factors of OS in these patients, the following demographic and socioeconomic factors had independent significance: marriage status and cohabitating family members.

Conclusion

This study suggests that demographic and socioeconomic status as well as clinical factors could influence the decision of further active treatment and prognosis of patients with BM of NSCLC.

Intratumoral Hemorrhage of the Cervical Spinal Schwannoma Presenting: Acute Quadriparesis

Schwannomas are the most common extramedullary spinal tumors, with chronic progressive symptoms being the most common presenting features. The acute hemorrhagic onset of a spinal schwannoma is a rare occurrence. Here, we report the case of a 37-year-old male who presented with complaint of neck pain and an acute onset of quadriparesis. MRI of his cervical spine revealed an intradural extramedullary lesion in the C2 to C3 cervical segment, with features of acute hemorrhage but mild enhancement. He was operated in emergency and complete microsurgical resection of tumor was achieved. Histopathology revealed features of an ancient schwannoma with hemorrhage. Postoperatively, the patient showed significant improvement.

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.

Microslit on a chip: A simplified filter to capture circulating tumor cells enlarged with microbeads

Microchips are widely used to separate circulating tumor cells (CTCs) from whole blood by virtues of sophisticated manipulation for microparticles. Here, we present a chip with an 8 μm high and 27.9 mm wide slit to capture cancer cells bound to 3 μm beads. Apart from a higher purity and recovery rate, the slit design allows for simplified fabrication, easy cell imaging, less clogging, lower chamber pressure and, therefore, higher throughput. The beads were conjugated with anti-epithelial cell adhesion molecules (anti-EpCAM) to selectively bind to breast cancer cells (MCF-7) used to spike the whole blood. The diameter of the cell-bead construct was in average 23.1 μm, making them separable from other cells in the blood. As a result, the cancer cells were separated from 5 mL of whole blood with a purity of 52.0% and a recovery rate of 91.1%, and also we confirmed that the device can be applicable to clinical samples of human breast cancer patients. The simple design with microslit, by eliminating any high-aspect ratio features, is expected to reduce possible defects on the chip and, therefore, more suitable for mass production without false separation outputs.

A Meta-analysis for Evaluating Efficacy of Neuroendoscopic Surgery versus Craniotomy for Supratentorial Hypertensive Intracerebral Hemorrhage

Objective

Hypertensive intracerebral hemorrhage is a potentially life-threatening neurological deficit with the highest morbidity and mortality. In recent years, neuroendoscopy has been used to treat intracerebral hemorrhages (ICHs). However, the choice of neuroendoscopic surgery or craniotomy for patients with ICHs is controversial. The objective of this meta-analysis was to assess the efficacy of neuroendoscopic surgery compared to craniotomy in patients with supratentorial hypertensive ICH.

Materials and Methods

A systematic electronic search was performed using online electronic databases such as Pubmed, Embase, and Cochrane library updated on December 2017. The meta-analysis was performed by only including studies designed as randomized controlled trials.

Results

Three randomized controlled trials met our inclusion criteria. Pooled analysis of death showed that neuroendoscopic surgery decreased the rate of death compared to craniotomy (RR=0.58, 95% CI: 0.26-1.29; P=0.18). Pooled results of complications showed that neuroendoscopic surgery tended to have fewer complications than craniotomy had (RR=0.37, 95% CI: 0.28-0.49; P < 0.0001).

Conclusion

Although the presenting analyses suggest that neuroendoscopic surgery should have fewer complications than craniotomy dose, it had no superior advantage in morbidity rate definitely. Therefore, it may be necessary for the neurosurgeons to select best optimal patients for individual treatment.

Extensive Pachymeningeal Dissemination of Glioblastoma Mimicking Chronic Subdural Hematoma: A Case Report

Meningeal dissemination (MDS) of glioblastoma is rare, although its incidence might have been underestimated. MDS of glioblastoma has a fatal course. Thus, rapid and precise diagnosis of MDS is important for further palliative treatment. Unfortunately, MDS of glioblastoma could be diagnosed at a delayed time, causing failure to treat patient optimally. Herein, we present a case of a 56-year-old male with MDS of glioblastoma mimicking chronic subdural hemorrhage (CSDH) after head trauma due to slip down. During treatment for CSDH, MDS of glioblastoma was not controlled appropriately. The patient succumbed to MDS of glioblastoma at 9 weeks after the date of diagnosis of CSDH which could be an MDS.

The Korean Society for Neuro-Oncology (KSNO) Guideline for WHO Grade II Cerebral Gliomas in Adults: Version 2019.01

BACKGROUND

There was no practical guideline for the management of patients with central nervous system tumor in Korea for many years. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, has developed the guideline for glioblastoma. Subsequently, the KSNO guideline for World Health Organization (WHO) grade II cerebral glioma in adults is established.

METHODS

The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified by searching PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL databases using specific and sensitive keywords as well as combinations of keywords regarding diffuse astrocytoma and oligodendroglioma of brain in adults.

RESULTS

Whenever radiological feature suggests lower grade glioma, the maximal safe resection if feasible is recommended globally. After molecular and histological examinations, patients with diffuse astrocytoma, isocitrate dehydrogenase (IDH)-wildtype without molecular feature of glioblastoma should be primarily treated by standard brain radiotherapy and adjuvant temozolomide chemotherapy (Level III) while those with molecular feature of glioblastoma should be treated following the protocol for glioblastomas. In terms of patients with diffuse astrocytoma, IDH-mutant and oligodendroglioma (IDH-mutant and 1p19q codeletion), standard brain radiotherapy and adjuvant PCV (procarbazine+lomustine+vincristine) combination chemotherapy should be considered primarily for the high-risk group while observation with regular follow up should be considered for the low-risk group.

CONCLUSION

The KSNO's guideline recommends that WHO grade II gliomas should be treated by maximal safe resection, if feasible, followed by radiotherapy and/or chemotherapy according to molecular and histological features of tumors and clinical characteristics of patients.

The Korean Society for Neuro-Oncology (KSNO) Guideline for Glioblastomas: Version 2018.01

BACKGROUND

There has been no practical guidelines for the management of patients with central nervous system (CNS) tumors in Korea for many years. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, started to prepare guidelines for CNS tumors from February 2018.

METHODS

The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of keywords.

RESULTS

First, the maximal safe resection if feasible is recommended. After the diagnosis of a glioblastoma with neurosurgical intervention, patients aged ≤70 years with good performance should be treated by concurrent chemoradiotherapy with temozolomide followed by adjuvant temozolomide chemotherapy (Stupp's protocol) or standard brain radiotherapy alone. However, those with poor performance should be treated by hypofractionated brain radiotherapy (preferred)±concurrent or adjuvant temozolomide, temozolomide alone (Level III), or supportive treatment. Alternatively, patients aged >70 years with good performance should be treated by hypofractionated brain radiotherapy+concurrent and adjuvant temozolomide or Stupp's protocol or hypofractionated brain radiotherapy alone, while those with poor performance should be treated by hypofractionated brain radiotherapy alone or temozolomide chemotherapy if the patient has methylated MGMT gene promoter (Level III), or supportive treatment.

CONCLUSION

The KSNO's guideline recommends that glioblastomas should be treated by maximal safe resection, if feasible, followed by radiotherapy and/or chemotherapy according to the individual comprehensive condition of the patient.

The Korean Society for Neuro-Oncology (KSNO) Guideline for WHO Grade III Cerebral Gliomas in Adults: Version 2019.01

Background

There was no practical guideline for the management of patients with central nervous system tumor in Korea in the past. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, developed the guideline for glioblastoma successfully and published it in Brain Tumor Research and Treatment, the official journal of KSNO, in April 2019. Recently, the KSNO guideline for World Health Organization (WHO) grade III cerebral glioma in adults has been established.

Methods

The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified by searches in PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL databases using specific and sensitive keywords as well as combinations of keywords. Scope of the disease was confined to cerebral anaplastic astrocytoma and oligodendroglioma in adults.

Results

Whenever radiological feature suggests high grade glioma, maximal safe resection if feasible is globally recommended. After molecular and histological examinations, patients with anaplastic astrocytoma, isocitrate dehydrogenase (IDH)-mutant should be primary treated by standard brain radiotherapy and adjuvant temozolomide chemotherapy whereas those with anaplastic astrocytoma, NOS, and anaplastic astrocytoma, IDH-wildtype should be treated following the protocol for glioblastomas. In terms of anaplastic oligodendroglioma, IDH-mutant and 1p19q-codeletion, and anaplastic oligodendroglioma, NOS should be primary treated by standard brain radiotherapy and neoadjuvant or adjuvant PCV (procarbazine, lomustine, and vincristine) combination chemotherapy.

Conclusion

The KSNO's guideline recommends that WHO grade III cerebral glioma of adults should be treated by maximal safe resection if feasible, followed by radiotherapy and/or chemotherapy according to molecular and histological features of tumors.

Prognostic Evaluation of Neurological Assessment of the Neuro-Oncology Scale in Glioblastoma Patients

BACKGROUND

The aims of this study were to investigate the role of the Neurological Assessment of Neuro-Oncology (NANO) scale in predicting the prognosis of patients with glioblastoma, and compare these results to predicted data of the Karnofsky Performance Scale (KPS), and Eastern Cooperative Oncology Group (ECOG)/World Health Organization (WHO) performance status. Additionally, we examined other prognostic factors in glioblastoma patients.

METHODS

The medical records of 76 patients with a new diagnosis of histologically ascertained glioblastoma in the period from January 2002 to December 2015 at the authors' institution were retrospectively reviewed. Clinical factors, including epidemiologic, radiologic, and therapeutic values were reviewed as well as the performance status assessed by the KPS, ECOG/WHO performance status, and NANO scale.

RESULTS

The mean overall survival was 19.8 months (95% confidence interval 15.2-25.4 months). At initial diagnosis, the mean value [±standard deviation (SD)] of KPS score, ECOG/WHO performance status, and NANO scale were 81 (±7.4), 1.3 (±0.6), and 7.3 (±3.8), respectively. Multivariate analysis for predicting survival showed odds ratios of KPS score, ECOG/WHO performance status, and NANO scale were 2.502 (≥80 vs. <80; p=0.024), 1.691 (0-1 vs. 2-5; p=0.047), and 2.763 (0-7 vs. 8-23; p=0.020), respectively. At the time of progression, the mean value (±SD) of KPS score, ECOG/WHO performance status, and NANO scale were 69 (±8.2), 1.6 (±0.7), and 11.4 (±4.2), respectively; multivariate analysis for predicting survival showed that the odd ratios for KPS score, ECOG/WHO performance status, and NANO scale were 2.007 (≥80 vs. <80; p=0.035), 1.321 (0-1 vs. 2-5; p=0.143), and 3.182 (0-7 vs. 8-23; p=0.002), respectively.

CONCLUSION

The NANO scale provided a more detailed and objective measure of neurologic function than that currently used for predicting the prognosis of glioblastoma patients, especially at the time of progression.

Function of cell-cycle regulators in predicting silent pituitary adenoma progression following surgical resection

The present study investigated the use of cell-cycle regulators for predicting the progression of silent pituitary adenoma (SPA) following surgical resection, via immunohistochemical analysis of tumor samples obtained by surgical resection. The medical records of patients diagnosed with SPA between January 2000 and December 2013 in the Samsung Changwon Hospital, Sungkyunkwan University School of Medicine (Changwon, South Korea) were reviewed. Immunohistochemical staining was performed on sections of the archived, paraffin-embedded tissues obtained by surgery, with all tissues stained for cell-cycle regulatory proteins p16, p15, p21, cyclin-dependent kinase (CDK)4, CDK6, retinoblastoma protein (pRb) and cyclin D1, as well as E3 ubiquitin-protein ligase mib1 (MIB-1) antigen and p53. The primary end-point was to investigate the expression of cell-cycle regulatory proteins in SPA. The secondary end-point was to estimate the progression-free survival of patients with SPA following surgical resection and to identify its association with the expression of cell-cycle regulatory proteins. Of the 127 SPA samples, 44 (34.6%) were from patients with progression during a mean follow-up period of 62.4 months (range, 24.2–118.9 months). Immunohistochemical overexpression was identified in 61 samples (48.0%) for p16, 38 samples (29.9%) for p15, 19 samples (15.0%) for p21, 49 samples (38.6%) for CDK4, 17 samples (13.4%) for CDK6, 57 samples (44.9%) for pRb and in 65 samples (51.2%) for cyclin D1. Multivariate analysis revealed that null cell adenoma [95% confidence interval (CI), 0.276–0.808], somatotroph SPAs (95% CI, 1.296–3.121), corticotroph SPAs (95% CI, 1.811–4.078), pluripotent SPAs (95% CI, 2.264–5.194), decreased expression of p16 (95% CI, 2.724–5.588), overexpression of pRb (95% CI, 2.557–5.333), cyclin D1 (95% CI, 1.894–4.122) and MIB-1 (95% CI, 1.561–4.133), increased mitotic index (95% CI, 1.228–4.079), increased p53 expression (95% CI, 1.307–4.065) and invasion into the cavernous sinus (95% CI, 3.842–7.502) predicted SPA progression following resection. The results of the present study suggested that specific cell-cycle regulators, including p16, cyclin D1 and pRb, were associated with SPA progression.

The Clinical Outcome of Hydroxyurea Chemotherapy after Incomplete Resection of Atypical Meningiomas

BACKGROUND

The aim of this study is to investigate the clinical results of adjuvant chemotherapy with hydroxyurea and to compare those with the results of postoperative radiotherapy after incomplete resection of atypical meningiomas (ATMNGs).

METHODS

We retrospectively reviewed the medical records of 84 patients with ATMNGs diagnosed in the period from January 2000 to December 2014. Clinical data included patient sex and age at the time of surgery, presenting symptoms at diagnosis, location and size of tumor, extent of surgery, use of postoperative radiotherapy or hydroxyurea chemotherapy, duration of follow-up, and progression. In terms of the extent of surgical resection, incomplete resection was defined as Simpson grade II-V.

RESULTS

Among the 85 patients, 55 (65.5%) patients underwent incomplete resection; 24 (43.6%) were treated with adjuvant hydroxyurea (group A), and 20 (36.4%) with postoperative radiotherapy (group B), and 11 (20.0%) underwent conservative treatment after surgery (group C). Twenty-five (45.5%) patients experienced the progression of tumors during the follow-up period (mean 47.7 months, range 12.4-132.1 months); 8 of 24 (33.3%) patients in group A, 7 of 20 (35.0%) patients in group B, and 10 of 11 (90.9%) patients in group C. The mean progression-free survival (PFS) was 30.9 months (range 6.4-62.3 months); 46.2 months in group A, 40.4 months in group B, and 11.9 months in group C (p=0.041). Multivariate analysis showed that Simpson grade (p=0.040), adjuvant treatment after surgery (p<0.001), increased Ki67 (p=0.017), mitotic index (p=0.034), and overexpression of p53 (p=0.026) predicted longer PFS.

CONCLUSION

This investigation suggested that adjuvant treatment after incomplete resection of ATMNGs are associated with longer PFS than conservative treatment, and that there is no difference of PFS between hydroxyurea chemotherapy and radiotherapy after surgery. Therefore, hydroxyurea chemotherapy can be considered as another adjuvant tool for the ATMNGs if the postoperative adjuvant radiotherapy cannot be applicable.

A Case of Primary Central Nervous System Lymphoma Located at Brain Stem in a Child

Primary central nervous system lymphoma (PCNSL) is an extranodal Non-Hodgkin's lymphoma that is confined to the brain, eyes, and/or leptomeninges without evidence of a systemic primary tumor. Although the tumor can affect all age groups, it is rare in childhood; thus, its incidence and prognosis in children have not been well defined and the best treatment strategy remains unclear. A nine-year old presented at our department with complaints of diplopia, dizziness, dysarthria, and right side hemiparesis. Magnetic resonance image suggested a diffuse brain stem glioma with infiltration into the right cerebellar peduncle. The patient was surgically treated by craniotomy and frameless stereotactic-guided biopsy, and unexpectedly, the histopathology of the mass was consistent with diffuse large B cell lymphoma, and immunohistochemical staining revealed positivity for CD20 and CD79a. Accordingly, we performed a staging work-up for systemic lymphoma, but no evidence of lymphoma elsewhere in the body was obtained. In addition, she had a negative serologic finding for human immunodeficient virus, which confirmed the histopathological diagnosis of PCNSL. She was treated by radiosurgery at 12 Gy and subsequent adjuvant combination chemotherapy based on high dose methotrexate. Unfortunately, 10 months after the tissue-based diagnosis, she succumbed due to an acute hydrocephalic crisis.

Surgical Results of Pure Endoscopic Endonasal Transsphenoidal Surgery for 331 Pituitary Adenomas: A 15-Year Experience from a Single Institution

BACKGROUND

The aim of this study is to report the results of pure endoscopic endonasal transsphenoidal surgery (EETSS) for pituitary adenomas (PAs) and to evaluate the efficacy and safety of this procedure. In addition, we tried to determine the predicting factors for progression of PAs.

METHODS

We reviewed the medical records of 331 consecutive patients who underwent pure EETSS of newly diagnosed PAs between April 1998 and December 2014. Demographic, endocrinologic, and radiologic features and their outcomes, complications, and hospital stay durations were retrospectively assessed in these patients.

RESULTS

There were 157 (47.4%) nonfunctioning adenomas and 174 (52.6%) hormone-secreting adenomas. Fifty-one (15.4%) complications were present in 39 patients postoperatively. The frequent complications were temporary and permanent diabetes insipidus (14 and 3 cases, respectively), syndrome of inappropriate antidiuretic hormone secretion (9 cases), and cerebrospinal fluid leaks (6 cases). There was only 1 death (0.3%) related to the procedure in this series. The patient's age (P = 0.047), the tumor size (P = 0.003), and the parasellar growth (P <0.001) were associated with the occurrence of complications on multivariate analysis. Progression occurred in 92 (27.8%) patients and the mean time-to-progression was 23.7 months (range, 3.7-52.4 months) after a mean follow-up period of 68.5 months. In the multivariate analysis, the tumor size (P = 0.021), the extent of surgery (P = 0.012), the Knosp classification (P = 0.002), and the MIB-1 index (P = 0.019) were associated with progression-free survival. The mean duration of hospitalization was 4.4 (±1.6) days.

CONCLUSIONS

The pure EETSS of PA provides acceptable and reasonable results representing a safe alternative procedure to the traditional transsphenoidal microscopic approach.

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.

Increased expression of the histone H3 lysine 4 methyltransferase MLL4 and the histone H3 lysine 27 demethylase UTX prolonging the overall survival of patients with glioblastoma and a methylated MGMT promoter

OBJECTIVE The purpose of the present study was to investigate the epigenetic and prognostic roles of an H3K4 methyltransferase (mixed lineage leukemia 4 [MLL4]) and H3K27 demethylase (ubiquitously transcribed tetratricopeptide repeat gene on X chromosome [UTX]) in progression-free survival (PFS) and overall survival (OS) of patients with glioblastoma (GBM) who were treated with radiotherapy, chemotherapy, or both after resection. In addition, the authors examined methylation at the promoter of the O-6-methylguanine-DNA methyltransferase ( MGMT) gene and other prognostic factors predicting length of PFS and OS in these patients. METHODS The medical records of 76 patients having a new diagnosis of histologically ascertained GBM in the period of January 2002 to December 2013 at the authors' institution were retrospectively reviewed. Immunohistochemical staining for MLL4 and UTX was performed on archived paraffin-embedded tissues obtained by biopsy or resection. The methylation status of the MGMT promoter in these tissues was determined by methylation-specific PCR analysis. RESULTS During the follow-up period (mean length 18.1 months, range 4.1-43.5 months), 68 (89.5%) of the patients died. The MGMT promoter was methylated in 49 patients (64.5%) and unmethylated in 27 (35.5%). The immunoreactivity pattern of UTX was identical to that of MLL4; increased expression of these 2 proteins was observed in samples from 34 patients (44.7%) and decreased expression in 42 patients (55.3%). The mean length of PFS was 9.2 months (95% CI 6.8-11.6 months). Extent of surgery, recursive partitioning analysis (RPA) class, and methylation status of the MGMT promoter were all associated with increased PFS in the multivariate analysis of factors predicting PFS. The mean length of OS was 18.6 months (95% CI 14.3-22.9 months). Patient age (p = 0.004), WHO performance status score (p = 0.019), extent of surgery (p = 0.007), RPA class (p = 0.036), methylation status of the MGMT promoter (p = 0.010), and increased expression of UTX-MLL4 (p = 0.001) were significantly associated with increased OS in multivariate analysis. Interestingly, in patients with an unmethylated MGMT promoter, immunoreactivity of UTX-MLL4 was not associated with changes in OS (p = 0.350). However, in the patients with a methylated MGMT promoter, increased UTX-MLL4 expression was strongly associated with increased OS (p < 0.001). CONCLUSIONS The results of this study suggest that increased expression of UTX-MLL4 positively influences the outcome of patients with GBM having a methylated MGMT promoter. Therefore, UTX-MLL4 immunoreactivity could be a useful predictor of the response to conventional treatment with radiotherapy or chemotherapy among GBM patients whose tumors have a methylated MGMT promoter.