Association between IDH mutational status and tumor-associated epilepsy or venous thromboembolism in patients with grade II and III astrocytoma.

In previous studies, isocitrate dehydrogenase (IDH) mutations were associated with tumor-associated epilepsy (TAE) and venous thromboembolism (VTE). We examined the relationship between IDH mutations in grade II/III astrocytomas and TAE/VTE according to the 2016 World Health Organization classification. The clinical data of patients with newly diagnosed grade II/III gliomas who were treated at Tohoku University Hospital from January 2010 to December 2018 were reviewed. Associations between TAE or VTE and the clinical/biological characteristics, histology, and IDH1/2 mutational status in patients with grade II/III gliomas were evaluated. Of the initial 137 patients (290 hospitalizations), 117 patients (203 hospitalizations) were included in the TAE group and 124 patients (213 hospitalizations) were included in the VTE group. Seventy-eight patients (66.7%) in the TAE group were diagnosed with astrocytoma and 38/78 (48.3%) presented with TAE. According to the multivariable analysis, the IDH mutational status and male sex were associated independently with an increased risk of TAE (p < 0.05). Eighty-five patients (68.5%) in the VTE group were diagnosed with astrocytoma. VTE was observed in 16/161 (9.9%) hospitalizations. According to the multivariable analysis, age, diffuse astrocytoma histology, and resection were associated independently with an increased risk of VTE. The decision tree analysis showed that TAE was more frequent in younger patients while VTE was more frequent in older patients. This study demonstrated that the IDH mutational status was associated with TAE but not with VTE. Therefore, a future large-scale study is needed to provide sufficient evidence. TAE was more common in young patients, while VTE was more common in the elderly.

H3K27M and TERT promoter mutations are poor prognostic factors in surgical cases of adult thalamic high-grade glioma.

BACKGROUND: Thalamic high-grade gliomas (HGGs) are rare tumors with a dismal prognosis. H3K27M and telomerase reverse transcriptase promoter (TERTp) mutations reportedly contribute to poor prognoses in HGG cases. We investigated the outcomes of surgically treated adult thalamic HGGs to evaluate the prognostic significance of H3K27M and TERTp mutations. METHODS: We retrospectively analyzed 25 adult patients with thalamic HGG who underwent maximum surgical resection from January 1997 to March 2020. The histological and molecular characteristics, progression-free survival (PFS), and overall survival (OS) of the patients were compared. For molecular characteristics, target sequencing was used to determine the H3F3A, HIST1H3B, and TERTp mutations. RESULTS: H3K27M mutations were detected in 12/25 (48.0%) patients. TERTp mutations were not detected in H3K27M-mutant gliomas but were detected in 8/13 (61.5%) of H3 wild-type gliomas. Although it was not significant, H3K27M-mutant gliomas tended to have a shorter PFS (6.7 vs 13.1 months; P = .2928) and OS (22.8 vs 24.4 months; P = .2875) than H3 wild-type gliomas. Moreover, the prognosis of TERTp-mutant gliomas was as poor as that of H3K27M-mutant gliomas. Contrary, 5 gliomas harboring both H3 and TERTp wild-type showed a better median PFS (59.2 vs 6.4 months; P = .0456) and OS (71.8 vs 24.4 months; P = .1168) than those harboring H3K27M or TERTp mutations. CONCLUSIONS: TERTp-mutant gliomas included in the H3 wild-type glioma group limited patient survival as they exhibited an aggressive course similar to H3K27M-mutant gliomas. Comprehensive molecular work-up for the H3 wild-type cases may further confirm this finding.

Hepatitis B virus reactivation during temozolomide administration for malignant glioma.

INTRODUCTION: The purpose of this study is to clarify the clinical features of temozolomide (TMZ)-related hepatitis B virus (HBV) reactivation and to identify HBV reactivation predictive factors. METHOD: We retrospectively reviewed the clinical course of 145 patients newly diagnosed or with recurrent malignant glioma treated with TMZ. Before treatment, we screened patients for HB surface antigen (HBsAg) positivity (HBV carrier) and HBsAg negativity. Patients were also screened for antibody for HB core antigen (anti-HBc) positivity and/or for HB surface antigen positivity (resolved HBV infection). The patients were monitored by HBV DNA, alanine, and aspartate aminotransaminase during and after the completion of TMZ. HBV carriers and those with resolved HBV infections with HBV reactivation received preemptive entecavir treatment. In those with resolved HBV infections, we analyzed clinical characters for the predictive factors for HBV reactivation. RESULTS: In one of two HBV carriers, HBV DNA turned positive 8 months after the completion of TMZ and entecavir. In four (16.7%) of 24 resolved HBV infections, HBV DNA turned detectable at completion of concomitant radiation and TMZ or during monthly TMZ. HBV DNA turned negative with entecavir in all patients without liver dysfunction. In resolved HBV infections, those with a high anti-HBc titer had significantly higher incidence of HBV reactivation than those with low anti-HBc titers (60% vs. 5.3%: p = 0.018). CONCLUSION: Screenings, monitoring, and preemptive entecavir were important for preventing TMZ-related HBV reactivations. Anti-HBc titers could be the predictive markers for HBV reactivation in the those with resolved HBV infections.

Frequent Clinical and Radiological Progression of Optic Pathway/Hypothalamic Pilocytic Astrocytoma in Adolescents and Young Adults.

Most cases of optic hypothalamic pilocytic astrocytoma (OHPA) develop during childhood, so few cases of histologically verified OHPA have been described in adolescents and young adults (AYA). To elucidate the clinical features of OHPA with histological verification in AYA, we reviewed the clinical and radiological finding of OHPA treated at our institute from January 1997 and July 2017. AYA are aged between 15 and 39 years. The clinical courses of 11 AYA patients with optic hypothalamic glioma (OHG) without neurofibromatosis type 1 were retrospectively reviewed. About six patients were diagnosed in childhood and followed up after 15 years of age, and five patients developed OHPA during AYA. Histological diagnosis, verified at initial presentation or recurrence, was pilocytic astrocytoma in 10 and pilomyxoid astrocytoma in one. After initial treatment including debulking surgery and/or chemotherapy, tumor progression occurred 16 times in seven patients as cyst formation, tumor growth, and intratumoral hemorrhage. Five of 10 patients suffered deterioration of visual function during AYA. One of 10 cases had endocrinopathies requiring hormone replacement at last follow-up examination. In conclusion, histological diagnoses of OHG before and in AYA were pilocytic astrocytoma or pilomyxoid astrocytoma. Both pediatric and AYA-onset OHPA demonstrate high incidences of tumor progression and visual dysfunctions in AYA, so that long-term follow up is essential after the completion of treatment for pediatric and AYA-onset OHPA. The optimal timing of debulking surgery and radiation therapy should be established to achieve the long-term tumor control and to preserve the visual function.

Endoscopic Hematoma Evacuation for Intracerebral Hemorrhage Under Local Anesthesia: Factors That Affect the Hematoma Removal Rate.

OBJECTIVE: Recent advances in endoscopic surgery have led to more patients being able to undergo endoscopic removal of hypertensive intracerebral hemorrhage (HICH). However, because of the minimal invasiveness, endoscopic HICH removal through a narrow surgical window can result in a low removal rate. The goal of the present study was to investigate the factors that affect the removal rate of HICH evacuation. METHODS: The data from 28 patients with supratentorial HICH who had undergone endoscopic hematoma evacuation were retrospectively analyzed. The inclusion criteria were spontaneous supratentorial HICH with a hematoma volume >30 mL, admission to the hospital within 24 hours of ictus, and a Glasgow coma scale score of ≥4. RESULTS: Of the 28 patients, 9 were women and 19 were men, ranging in age from 41 to 86 years (mean, 60.7 ± 12.7). The hematoma location was the basal ganglia in 25 patients and subcortical in 3 patients. The mean preoperative hematoma volume was 62.4 ± 22.5 mL. The hematoma removal rate was <60% for 11 patients (poor evacuation group) and ≥60% for in 17 patients (good evacuation group). Comparing the 2 groups, chronic renal failure treated with hemodialysis (P = 0.0072, χ2 test), liver cirrhosis (P = 0.023, χ2 test), and surgeon experience with ≥10 cases of endoscopic HICH removal (P = 0.016, χ2 test) were significant factors related to the HICH removal rate. CONCLUSION: To achieve a good removal rate, surgeons should have experience performing the endoscopic procedure. Also, patients with end-stage chronic renal failure or liver cirrhosis should be excluded.

Continuous Minor Bleeding from Tumor Surface in Patients with Craniopharyngiomas: Case Series of Nonobstructive Hydrocephalus.

Nonobstructive hydrocephalus in patients with craniopharyngiomas is uncommon. We describe our surgical series of 25 consecutive patients with craniopharyngioma who presented with hydrocephalus. Obstructive hydrocephalus was evident in most cases, and nonobstructive hydrocephalus was revealed in three cases. Even after improvement of cerebrospinal fluid (CSF) pathway obstruction by tumor removal, 10 patients (40%) required CSF diversion. Preoperative imaging study revealed thin intraventricular hemorrhage or superficial siderosis in five cases, and CSF examination revealed hemosiderin-laden phagocytes in one case. These findings indicate continuous bleeding into the CSF that might be associated with CSF malabsorption. We also describe a representative case of craniopharyngioma associated with nonobstructive hydrocephalus due to continuous minor bleeding from the tumor surface in a 62-year-old man with a complaint of disorientation and a decline in daily living activity.Our study demonstrated that minor bleeding into the CSF is a possible mechanism of the development of nonobstructive hydrocephalus in patients with craniopharyngiomas.

Convection-enhanced delivery of sulfasalazine prolongs survival in a glioma stem cell brain tumor model.

Expression of CD44 in glioma cells was previously correlated with tumor grade and is considered a stem cell marker. CD44 stabilizes the cystine-glutamate transporter (xCT) and inhibits apoptosis in cancer stem cells (CSCs). Recently it was found that Sulfasalazine (SSZ), an anti-inflammatory drug, acts as an inhibitor of xCT and therefore has potential as a targeted therapy for CSCs. In this study, we tested an efficacy of SSZ against glioma stem cell model developed in rats. As poor penetration of blood-brain barrier resulted in insufficient efficacy of systemic SSZ treatment, SSZ was delivered locally with convection-enhanced delivery (CED). In vitro, expression of CD44 in glioma cells and efficacy of SSZ against glioma cells and glioma stem cells were confirmed. SSZ demonstrated anti-proliferative activity in a dose dependent manner against these cells. This activity was partially reversible with the addition of antioxidant, N-acetyl-L-cysteine, to the medium. In vivo, CED successfully delivered SSZ into the rat brain parenchyma. When delivered at 5 mM concentration, which was the highest possible concentration when SSZ was dissolved in water, CED of SSZ resulted in almost no tissue damage. Against highly malignant bRiTs-G3 brain tumor xenografted rat model; the glioma stem cell model, CED of SSZ at 5 mM concentration induced apoptosis and prolonged survival. Consequently, CED of SSZ induced glioma stem cell death without evidence of tissue damage to normal brain parenchyma. This strategy may be a promising targeted treatment against glioma stem cells.

Sarcoma-like tumor originating from oligodendroglioma.

We present a case of sarcoma occurring at a site of resected oligodendroglioma without preceding radiotherapy or chemotherapy. Oligosarcoma occurring at sites of resected oligodendroglioma or anaplastic oligodendroglioma with sarcomatous components are rare. Although meningioma or sarcoma-like lesions are sometimes reported after glioma-targeted radiotherapy, those without preceding radiotherapy are quite rare. Moreover, cases of sarcoma without oligodendroglial components occurring at a site of resected oligodendroglioma have never been reported. In this case, fluorescent in situ hybridization analysis revealed 1p/19q co-deletion in both the first tumor and second tumors. Additionally, immunohistochemistry revealed mutated isocitrate dehydrogenase 1 in both tumors. Taken together, these findings suggest a monoclonal tumor origin. Consequently, this case may indicate a new mechanism of development of sarcomatous lesions occurring at the site of a resected glioma.

Local convection-enhanced delivery of an anti-CD40 agonistic monoclonal antibody induces antitumor effects in mouse glioma models.

BACKGROUND: Glioblastoma is one of the most malignant brain tumors in adults and has a dismal prognosis. In a previous report, we reported that CD40, a TNF-R-related cell surface receptor, and its ligand CD40L were associated with glioma outcomes. Here we attempted to activate CD40 signaling in the tumor and determine if it exerted therapeutic efficacy. METHODS: CD40 expression was examined in 3 mouse glioma cell lines (GL261, NSCL61, and bRiTs-G3) and 5 human glioma cell lines (U87, U251, U373, T98, and A172). NSCL61 and bRiTs-G3, as glioma stem cells, also expressed the glioma stem cell markers MELK and CD44. In vitro, we demonstrated direct antitumor effects of an anti-CD40 agonistic monoclonal antibody (FGK45) against the cell lines. The efficacy of FGK45 was examined by local convection-enhanced delivery of the monoclonal antibody against each glioma model. RESULTS: CD40 was expressed in all mouse and human cell lines tested and was found at the cell membrane of each of the 3 mouse cell lines. FGK45 administration induced significant, direct antitumor effects in vitro. The local delivery of FGK45 significantly prolonged survival compared with controls in the NSCL61 and bRiTs-G3 models, but the effect was not significant in the GL261 model. Increases in apoptosis and CD4(+) and CD8(+) T cell infiltration were observed in the bRiTs-G3 model after FGK45 treatment. CONCLUSIONS: Local delivery of FGK45 significantly prolonged survival in glioma stem cell models. Thus, local delivery of this monoclonal antibody is promising for immunotherapy against gliomas.

Intraparenchymal ultrasound application and improved distribution of infusate with convection-enhanced delivery in rodent and nonhuman primate brain.

OBJECT Convection-enhanced delivery (CED) is an effective drug delivery method that delivers high concentrations of drugs directly into the targeted lesion beyond the blood-brain barrier. However, the drug distribution attained using CED has not satisfactorily covered the entire targeted lesion in tumors such as glioma. Recently, the efficacy of ultrasound assistance was reported for various drug delivery applications. The authors developed a new ultrasound-facilitated drug delivery (UFD) system that enables the application of ultrasound at the infusion site. The purpose of this study was to demonstrate the efficacy of the UFD system and to examine effective ultrasound profiles. METHODS The authors fabricated a steel bar-based device that generates ultrasound and enables infusion of the aqueous drug from one end of the bar. The volume of distribution (Vd) after infusion of 10 ml of 2% Evans blue dye (EBD) into rodent brain was tested with different frequencies and applied voltages: 252 kHz/30 V; 252 kHz/60 V; 524 kHz/13 V; 524 kHz/30 V; and 524 kHz/60 V. In addition, infusion of 5 mM gadopentetate dimeglumine (Gd-DTPA) was tested with 260 kHz/60 V, the distribution of which was evaluated using a 7-T MRI unit. In a nonhuman primate (Macaca fascicularis) study, 300 µl of 1 mM Gd-DTPA/EBD was infused. The final distribution was evaluated using MRI. Two-sample comparisons were made by Student t-test, and 1-way ANOVA was used for multiple comparisons. Significance was set at p < 0.05. RESULTS After infusion of 10 µl of EBD into the rat brain using the UFD system, the Vds of EBD in the UFD groups were significantly larger than those of the control group. When a frequency of 252 kHz was applied, the Vd of the group in which 60 V was applied was significantly larger than that of the group in which 30 V was used. When a frequency of 524 kHz was applied, the Vd tended to increase with application of a higher voltage; however, the differences were not significant (1-way ANOVA). The Vd of Gd-DTPA was also significantly larger in the UFD group than in the control group (p < 0.05, Student t-test). The volume of Gd-DTPA in the nonhuman primate used in this study was 1209.8 ± 193.6 mm(3). This volume was much larger than that achieved by conventional CED (568.6 ± 141.0 mm(3)). CONCLUSIONS The UFD system facilitated the distribution of EBD and Gd-DTPA more effectively than conventional CED. Lower frequency and higher applied voltage using resonance frequencies might be more effective to enlarge the Vd. The UFD system may provide a new treatment approach for CNS disorders.

[Perforating Artery Injury during Microsurgery for Internal Carotid Artery Bifurcation Aneurysms].

Internal carotid artery bifurcation aneurysms(ICB-ANs)are relatively rare and are difficult to occlude by direct clipping without perforating artery injury(PAI). We retrospectively analyzed 11 aneurysms in 10 cases. PAI was identified in 5 of 10 cases on postoperative computed tomography(CT)or magnetic resonance imaging(MRI), and 2 of these patients were symptomatic. PAIs were distributed in the caudate nucleus and/or the genu of the internal capsule. PAI occurred in 3 of 5 cases in which indocyanine green videoangiography(ICG-VAG)was performed. ICG-VAG is a helpful tool visualizing blood flow of vessels in surgical fields. However, PAI is a potential risk in direct clipping of ICB-ANs even if adjacent perforating arteries were observed using ICG-VAG.

CD40/CD40L expression correlates with the survival of patients with glioblastomas and an augmentation in CD40 signaling enhances the efficacy of vaccinations against glioma models.

BACKGROUND: The prognosis of glioblastoma (GBM) remains poor; therefore, effective therapeutic strategies need to be developed. CD40 is a costimulatory molecule whose agonistic antibody has been shown to activate antitumor effects. Recently, CD40 has been extensively targeted for immunotherapeutic purposes. METHODS: Expressions of CD40/CD40L mRNAs were examined in 86 cases of World Health Organization grade IV GBM and 36 cases of grade III gliomas and correlated with outcomes. CD40 signaling was employed to augment the efficacy of immunotherapy against gliomas. The efficacy of FGK45, an agonistic antibody for CD40, was examined by adding it to a tumor lysate-based subcutaneous vaccination against a GL261 glioma model and an NSCL61 glioma-initiating cell-like cell tumor model. RESULTS: We demonstrated for the first time using quantitative PCR that grade III gliomas express higher levels of CD40/CD40L than does grade IV GBM. The higher expression of CD40/CD40L was associated with good prognoses in patients with GBM. Addition of FGK45 to the subcutaneous tumor cell lysate-based vaccination significantly prolonged survival in both tumor models. However, the efficacy was modest in NSCL61-model mice. Therefore, we established combination immunotherapeutic strategies using FGK45 and OX86, an agonistic antibody for OX40. Combination immunotherapy significantly prolonged survival with synergistic effects. Apoptosis increased and proliferation decreased in tumors treated with combination immunotherapy. CONCLUSIONS: The high expression of CD40/CD40L can be used as a biomarker for better prognoses in patients with gliomas. Immunotherapy using FGK45 significantly prolonged survival and represents a potential therapeutic strategy for gliomas including glioma-initiating cells.

OX40 ligand expressed in glioblastoma modulates adaptive immunity depending on the microenvironment: a clue for successful immunotherapy.

BACKGROUND: Glioblastoma is the most malignant human brain tumor and has a dismal prognosis; however, some patients show long-term survival. The interaction between the costimulatory molecule OX40 and its ligand OX40L generates key signals for T-cell activation. The augmentation of this interaction enhances antitumor immunity. In this present study, we explored whether OX40 signaling is responsible for antitumor adaptive immunity against glioblastoma and also established therapeutic antiglioma vaccination therapy. METHODS: Tumor specimens were obtained from patients with primary glioblastoma (n = 110) and grade III glioma (n = 34). Quantitative polymerase chain reaction (PCR), flow cytometry, and immunohistochemistry were used to analyze OX40L expression in human glioblastoma specimens. Functional consequences of OX40 signaling were studied using glioblastoma cell lines, mouse models of glioma, and T cells isolated from human subjects and mice. Cytokine production assay with mouse regulatory T cells was conducted under hypoxic conditions (1.5% O2). RESULTS: OX40L mRNA was expressed in glioblastoma specimens and higher levels were associated with prolonged progression-free survival of patients with glioblastoma, who had undergone gross total resection. In this regard, OX40L protein was expressed in A172 human glioblastoma cells and its expression was induced under hypoxia, which mimics the microenvironment of glioblastoma. Notably, human CD4 T cells were activated when cocultured in anti-CD3-coated plates with A172 cells expressing OX40L, as judged by the increased production of interferon-γ. To confirm the survival advantage of OX40L expression, we then used mouse glioma models. Mice bearing glioma cells forced to express OX40L did not die during the observed period after intracranial transplantation, whereas all mice bearing glioma cells lacking OX40L died. Such a survival benefit of OX40L was not detected in nude mice with an impaired immune system. Moreover, compared with systemic intraperitoneal injection, the subcutaneous injection of the OX40 agonist antibody together with glioma cell lysates elicited stronger antitumor immunity and prolonged the survival of mice bearing glioma or glioma-initiating cell-like cells. Finally, OX40 triggering activated regulatory T cells cultured under hypoxia led to the induction of the immunosuppressive cytokine IL10. CONCLUSION: Glioblastoma directs immunostimulation or immunosuppression through OX40 signaling, depending on its microenvironment.

Malignant clinical features of anaplastic gliomas without IDH mutation.

BACKGROUND: Diagnosis of WHO grade III anaplastic gliomas does not always correspond to its clinical outcome because of the isocitrate dehydrogenase (IDH) gene status. Anaplastic gliomas without IDH mutation result in a poor prognosis, similar to grade IV glioblastomas. However, the malignant features of anaplastic gliomas without IDH mutation are not well understood. The aim of this study was to examine anaplastic gliomas, in particular those without IDH mutation, with regard to their malignant features, recurrence patterns, and association with glioma stem cells. METHODS: We retrospectively analyzed 86 cases of WHO grade III anaplastic gliomas. Data regarding patient characteristics, recurrence pattern, and prognosis were obtained from medical records. We examined molecular alterations such as IDH mutation, 1p19q loss, TP53 mutation, MGMT promoter methylation, Ki67 labeling index, and CD133, SOX2, and NESTIN expression. RESULTS: Of the 86 patients with anaplastic gliomas, 58 carried IDH mutation, and 40 experienced recurrence. The first recurrence was local in 25 patients and distant in 15. Patients without IDH mutation exhibited significantly higher CD133 and SOX2 expression (P = .025 and .020, respectively) and more frequent distant recurrence than those with IDH mutation (P = .022). CONCLUSIONS: Patients with anaplastic gliomas without IDH mutation experienced distant recurrence and exhibited glioma stem cell markers, indicating that this subset may share some malignant characteristics with glioblastomas.