Genomic landscape of glioblastoma without IDH somatic mutation in 42 cases: a comprehensive analysis using RNA sequencing data.

PURPOSE: Glioblastoma is a malignant brain tumor with a poor prognosis. Genetic mutations associated with this disease are complex are not fully understood and require further elucidation for the development of new treatments. The purpose of this study was to comprehensively analyze genetic mutations in glioblastomas and evaluate the usefulness of RNA sequencing. PATIENTS AND METHODS: We analyzed 42 glioblastoma specimens that were resected in routine clinical practice and found wild-type variants of the IDH1 and IDH2 genes. RNA was extracted from frozen specimens and sequenced, and genetic analyses were performed using the CLC Genomics Workbench. RESULTS: The most common genetic alterations in the 42 glioblastoma specimens were TP53 mutation (28.6%), EGFR splicing variant (16.7%), EGFR mutation (9.5%), and FGFR3 fusion (9.5%). Novel genetic mutations were detected in 8 patients (19%). In 12 cases (28.6%), driver gene mutations were not detected, suggesting an association with PPP1R14A overexpression. Our findings suggest the transcription factors SOX10 and NKX6-2 are potential markers in glioblastoma. CONCLUSION: RNA sequencing is a promising approach for genotyping glioblastomas because it provides comprehensive information on gene expression and is relatively cost-effective.

[A Case of Miliary Brain Metastases Molecularly Diagnosed as Silent Lung Adenocarcinoma Origin].

A 60-year-old woman was referred to our hospital because of possible miliary brain metastases of unknown primary origin. On admission, she was alert and had no apparent motor weakness. Neuroradiological examinations revealed more than 100 small enhancing lesions, some of which had undergone cystic changes, suggesting multiple metastases. However, plain chest and abdominal CT revealed no abnormalities, and fluorodeoxyglucose-positron emission tomography could not reveal the primary origin of the cancer. Blood examination revealed no apparent abnormalities, except for tumor markers, including pro-gastrin-releasing peptide and carcinoembryonic antigen. On day 22, the patient underwent a biopsy through right frontal craniotomy. Histopathological findings indicated metastases from cancer. Immunohistochemistry was positive for cytokeratin(CK)7 and thyroid transcription factor-1 while negative for CK20(-), CK5/6, and p40, resulting in the diagnosis of lung adenocarcinoma. Genetic testing showed negative for EGFR mutation and positive for ALK fusion gene. From the day 48, whole brain radiotherapy was started, and the ALK inhibitor was prescribed from day 64. Metastatic brain tumors of unknown primary are rare. Miliary brain metastases from an unknown primary origin are rare. To our knowledge, this is the first case of military brain metastases of an unknown primary origin, which was later determined to have originated from ALK fusion-positive lung cancer.

Single-Fraction Helical Tomotherapy for Ameloblastic Carcinoma.

Ameloblastic carcinoma (AC) is a rare malignant odontogenic tumor. Surgical resection of the tumor is the mainstay of its treatment. To date, radiotherapy for this tumor remains controversial. This report describes a case of AC with intracranial extension and provides the first report of the efficacy of single-fraction helical tomotherapy for the treatment of residual AC after surgical resection.

An innovative technique for detecting the caudal end of occluded inferior petrosal sinus in cavernous arteriovenous fistula using intravascular ultrasonography--technical note.

INTRODUCTION: Although cavernous sinus (CS) dural arteriovenous fistulas (d-AVFs) are usually treated with transvenous embolization (TVE) via the inferior petrosal sinus (IPS), IPSs are sometimes thrombosed and angiographically invisible. In such cases, the first obstacle to TVE is detecting the entry to the IPS. We report a new technique for TVE via IPS using intravascular ultrasonography (IVUS). METHODS: Three consecutive cases of CS d-AVF with ipsilateral or bilateral IPS occlusion were involved in this study. On TVE, the orifice of the IPS was investigated with IVUS placed in the jugular vein or jugular bulb. RESULTS: This technique has been successfully adapted in all three cases. In two of these cases, IPS was well visualized with the help of IVUS, and TVE was successfully performed. CONCLUSION: To our knowledge, this is the first report to mention the usefulness of IVUS for detecting angiographically occult IPS.

Adult classical glioblastoma with a BRAF V600E mutation.

The B-Raf proto-oncogene serine/threonine kinase (B-Raf) is a member of the Raf kinase family. The BRAF V600E mutation occurs frequently in certain brain tumors such as pleomorphic xanthoastrocytoma, ganglioglioma, and pilocytic astrocytoma, and less frequently in epithelioid and giant cell glioblastoma. BRAF V600E mutation in these cases has been canonically detected using Sanger sequencing or immunohistochemistry but not with next-generation sequencing (NGS). Moreover, to our knowledge, there is no detailed report of the BRAF V600E mutation in an adult glioblastoma with classical histologic features (c-GBM). Therefore, we performed NGS analysis to determine the mutational status of BRAF of 13 glioblastomas (GBMs) (11 primary and 2 secondary cases) and detected one tumor harboring the BRAF V600E mutation. We report here the detection of the BRAF V600E mutation in a patient with c-GBM and describe the patient's clinical course as well as the results of histopathological analysis.

A Case of Multifocal Ectopic Germinoma Manifesting with Medial Longitudinal Fasciculus Syndrome.

Introduction: Intracranial germinomas mainly arise in the pineal gland or neurohypophyseal region. The basal ganglia have been reported as the site of occurrence for ectopic germinomas, whereas other sites have been rarely described. We experienced a case of multifocal ectopic germinoma that arose in the septum pellucidum and the dorsal brain stem, not including the pineal gland, neurohypophysis, and basal ganglia of ectopic germinoma in a pregnant woman. Case Presentation: The patient initially presented to our institution with complaints of diplopia in the past 14 weeks of gestation, and imaging later revealed two intracranial neoplastic lesions, with one lesion involving the septum pellucidum and the other involving the dorsal brainstem. Both tumors were partially excised via a transcortical approach. Based on the results of pathology and immunohistochemistry, the patient was diagnosed with germinoma, and the intraoperative spinal fluid cytology was class V in Papanicolaou classification. The patient received three courses of ifosfamide, carboplatin, and etoposide together with whole-brain irradiation, which resulted in complete elimination of the tumors. No evidence of recurrence was identified after 18 months. Conclusion: The results illustrated the need to consider germinoma in the differential diagnosis if the lesions involve midline structures such as the septum pellucidum or dorsal brainstem. Given the rarity of germinoma arising outside the pineal gland and neurohypophyseal region, these findings provide key insights into the diagnosis and treatment of this disease.

Prediction of intraoperative blood loss in pediatric posterior fossa tumors by neuroradiological evaluation: preliminary study.

BACKGROUND: Hemorrhage management is crucial for surgical resection of pediatric posterior-fossa tumors (PPFTs). Tumor volume and vascularity on preoperative magnetic resonance imaging (MRI) can help predict and control intraoperative blood loss (IBL). The present study aimed to assess the correlation between MRI features and IBL in PPFTs. METHODS: Eleven patients treated for PPFTs at our hospital using the transcerebellomedullary fissure approach were enrolled, including five (45.5%) males and six (54.5%) females, with a median age of 10 (range, 4-16) years. Nine patients with medulloblastoma, one with ependymoma, and one with atypical teratoid/rhabdoid tumor were included. Using susceptibility-weighted imaging-based intratumoral susceptibility signal (ITSS) grade as an index of tumor vascularity, we performed univariate analysis of the association of degree of vascularity (ITSS grade 0-2 vs. 3) and multivariate analysis of IBL. RESULTS: Univariate analysis showed that the high vascularity group (ITSS grade 3) had significantly larger tumor volume (p = 0.009) and higher IBL (p = 0.004). In multivariate analysis of age, tumor volume, ITSS grade, cerebral blood volume, and extent of resection, tumor volume was the only significant factor (p = 0.001); however, ITSS grade was also positively associated with IBL (p = 0.074). CONCLUSION: In this study, tumor volume and vascularity of PPFTs were strongly correlated, and tumor volume was the sole factor significantly associated with IBL. This study suggests that ITSS grade and tumor volume collaboratively influence IBL in surgical resection of PPFTs. IBL should be assessed based on MRI features, and suitable treatment strategies should be established.

Neuroradiological, genetic and clinical characteristics of histone H3 K27-mutant diffuse midline gliomas in the Kansai Molecular Diagnosis Network for CNS Tumors (Kansai Network): multicenter retrospective cohort.

This study aims to elucidate the clinical and molecular characteristics, treatment outcomes and prognostic factors of patients with histone H3 K27-mutant diffuse midline glioma. We retrospectively analyzed 93 patients with diffuse midline glioma (47 thalamus, 24 brainstem, 12 spinal cord and 10 other midline locations) treated at 24 affiliated hospitals in the Kansai Molecular Diagnosis Network for CNS Tumors. Considering the term "midline" areas, which had been confused in previous reports, we classified four midline locations based on previous reports and anatomical findings. Clinical and molecular characteristics of the study cohort included: age 4-78 years, female sex (41%), lower-grade histology (56%), preoperative Karnofsky performance status (KPS) scores ≥ 80 (49%), resection (36%), adjuvant radiation plus chemotherapy (83%), temozolomide therapy (76%), bevacizumab therapy (42%), HIST1H3B p.K27M mutation (2%), TERT promoter mutation (3%), MGMT promoter methylation (9%), BRAF p.V600E mutation (1%), FGFR1 mutation (14%) and EGFR mutation (3%). Median progression-free and overall survival time was 9.9 ± 1.0 (7.9-11.9, 95% CI) and 16.6 ± 1.4 (13.9-19.3, 95% CI) months, respectively. Female sex, preoperative KPS score ≥ 80, adjuvant radiation + temozolomide and radiation ≥ 50 Gy were associated with favorable prognosis. Female sex and preoperative KPS score ≥ 80 were identified as independent good prognostic factors. This study demonstrated the current state of clinical practice for patients with diffuse midline glioma and molecular analyses of diffuse midline glioma in real-world settings. Further investigation in a larger population would contribute to better understanding of the pathology of diffuse midline glioma.

Prognostic value of isocitrate dehydrogenase 1, O6-methylguanine-DNA methyltransferase promoter methylation, and 1p19q co-deletion in Japanese malignant glioma patients.

BACKGROUND: To determine the prognostic value of isocitrate dehydrogenase 1 (IDH1) mutation, O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation, and 1p/19q co-deletion in Japanese patients with malignant gliomas. METHODS: We studied 267 malignant gliomas, which included 171 glioblastomas (GBMs), 40 anaplastic astrocytomas (AAs), 30 anaplastic oligodendrogliomas (AOs), and 26 anaplastic oligoastrocytomas (AOAs). These malignant gliomas were divided into 2 groups (Group 1: GBM + AA, Group 2: AO + AOA) according to the presence of the oligodendroglioma component. We examined IDH1 mutation and MGMT promoter methylation in each group by direct sequencing and methylation-specific PCR, respectively. We further examined 1p/19q co-deletion in Group 2 by fluorescence in situ hybridization. Survival between groups was compared by Kaplan-Meier analysis. RESULTS: In Group 1, patients with IDH1 mutations exhibited a significantly longer survival time than patients with wild-type IDH1. However, no significant difference was observed in Group 2, although patients with IDH1 mutations tended to show prolonged survival. For both Group 1 and Group 2, patients with MGMT methylation survived longer than those without this methylation. Further, patients with 1p/19q co-deletion showed significantly better outcome in Group 2. CONCLUSIONS: Our study confirms the utility of IDH1 mutations and MGMT methylation in predicting the prognosis of Group 1 patients (GBM + AA) and demonstrated that IDH1 mutations may serve as a more reliable prognostic factor for such patients. We also showed that MGMT methylation and 1p/19q co-deletion rather than IDH1 mutations were prognostic factors for Group 2 patients (AOA + AO). Our study suggests that patients survive longer if they have IDH1 mutations and undergo total resection. Further, irrespective of MGMT promoter methylation status, the prognosis of glioma patients can be improved if total resection is performed. Moreover, our study includes the largest number of Japanese patients with malignant gliomas that has been analyzed for these three markers. We believe that our findings will increase the awareness of oncologists in Japan of the value of these markers for predicting prognosis and designing appropriate therapeutic strategies for treating this highly fatal disease.

Biopsy-proven Primary CNS Lymphoma in the Medulla Oblongata Presenting as Anorexia.

Eating disorders caused by brain tumors are infrequently seen. Recent studies revealed that a neurocircuit from the nucleus tractus solitarius of the medulla oblongata to the hypothalamus participates in the control of appetite. Among brain tumors, those located in the brain stem, especially a solitary one in the medulla oblongata, are rare. Tumors in the brainstem are generally considered gliomas, and with the difficulty in reaching the lesion, treatment without histological confirmation is often performed. However, there are a few reported cases of medulla oblongata tumors other than gliomas. We describe a case of a 56-year-old man who presented with persistent anorexia. Magnetic resonance images revealed a solitary tumor in the medulla oblongata. After several examinations, craniotomy for the biopsy of the tumor using the cerebellomedullary fissure approach was carried out and primary central nervous system lymphoma (PCNSL) was histologically proven. The patient was treated with effective adjuvant therapy and was discharged home after he recovered from the symptoms. No tumor recurrence was recognized 24 months after surgery. A PCNSL arising only from the medulla oblongata is very rare, and anorexia can be an initial symptom of a tumor in the medulla oblongata. Surgical intervention is safely achieved and is a key to a better clinical outcome.

Analysis of False-negative Findings of the Incomparable Accuracy and Swiftness of Flow Cytometric Diagnosis of Primary Central Nervous System Lymphoma.

Primary central nervous system lymphoma (PCNSL), a relatively rare brain tumor, bears a dire prognosis. On occasion, the rapid progression of the tumor makes immediate diagnosis and initiation of therapy imperative. To achieve swift diagnosis, we adopt flow cytometry (FCM) in addition to conventional histopathology. This study aimed to reveal the utility of FCM diagnosis for PCNSL and the cause of false-negative results of FCM diagnosis. We investigated 33 patients with suspected PCNSL on neuroradiological findings and received both FCM and histological diagnosis. The patients' electronic medical records were investigated, and histological findings, results of FCM, and other clinical data were evaluated. Overall, 27 patients (14 males and 13 females) were diagnosed with PCNSL by histological confirmation. The median age at diagnosis was 68 years. FCM analysis showed lymphoma pattern in 24 cases; however, FCM results did not show lymphoma pattern (sensitivity: 88.9%, specificity: 100%) in the other three lymphoma cases (FCM discordant: FCM-D) and six nonlymphomatous tumor cases. Analysis of FCM-D cases showed the infiltration of T lymphocytes or astrocytes into the tumor tissue, indicating tumor microenvironmental reaction; it is assumed that these reactions deceived FCM diagnosis. The survival of FCM-D patients was superior to FCM concordant counterpart, although the difference was not significant (p = 0.459). The diagnosis of PCNSL by FCM is rapid and highly reliable. Some FCM-D cases are PCNSLs with strong tumor microenvironmental reactions.

Bacterial meningitis caused by nontraumatic cerebrospinal fluid rhinorrhea with aqueductal stenosis: A case report.

Background: Nontraumatic cerebrospinal fluid (CSF) rhinorrhea associated with aqueductal stenosis is rare. The resulting CSF leakage may cause bacterial meningitis, and appropriately timed surgical treatment should be considered. Case Description: A 28-year-old woman with obstructive hydrocephalus secondary to aqueductal stenosis presented with intermittent nasal discharge. CSF rhinorrhea was suspected, but she refused surgery. During the course of conservative treatment, she developed meningitis. Exacerbation of hydrocephalus and CSF rhinorrhea was suspected, and the patient underwent endoscopic third ventriculostomy after recovery from meningitis. Postoperatively, ventricular size decreased and CSF leakage completely resolved. There was no recurrence of hydrocephalus or rhinorrhea. Conclusion: Patients with intermittent CSF rhinorrhea due to exacerbation of hydrocephalus are at high risk for bacterial meningitis. Appropriately timed surgical treatment results in a favorable outcome.

Development of Needle Guide Unit Considering Buckling Bone-Perforation Control Strategy Based on Computed Tomography-Guided Needle Insertion Robot.

A computed tomography (CT)-guided robotic assistance system is useful for needle insertion into metastatic carcinoma of vertebrae, which has limited pathways. However, the use of conventional needles in this procedure can result in bone fracture in the perforation area caused by the reaction force of the inserted needle. In this study, we developed a multistage retractable needle guide unit that avoids the buckling and crushing of the needle tip that commonly occur in 25-gauge ultrafine needles. First, we clarified a relationship between the shape of the guide and the termination factor when a buckling load is applied to the needle. Next, we revealed the point at which the plastic deformation of the needle occurred when the bone is drilled. Based on these results, we developed a guide unit with the reaction force set to an appropriate value. Finally, an evaluation test of bone needle insertion was conducted on porcine vertebrae with using the developed needle guide unit equipped with a 25-gauge needle. The needle penetrated the vertebra without buckling or crushing of the needle tip, which demonstrates the value of this multistage retractable needle guide unit when ultrafine needles are required. Clinical Relevance- Cancer tumors often metastasize to bones. There is a treatment called percutaneous vertebroplasty which restores the patient's quality of life by injecting poly (methyl methacrylate) (PMMA) into a bone. It helps to reinforce the bone that has become brittle due to cancer metastasis to the vertebral body or osteoporosis. This treatment often involves puncture of the vertebrae but the limited puncture pathway makes it difficult to perform the treatment manually. Therefore it is necessary to construct a system that supports accurate puncture by a robot such as the proposed method.

Transient and Recurrent Pulmonary Infiltrations Associated with Familial Mediterranean Fever.

Chest symptoms and pleural effusion due to serositis in familial Mediterranean fever (FMF) are occasionally misdiagnosed as acute pneumonia. However, the actual pulmonary involvement of FMF is extremely rare. A 67-year-old man was referred to our hospital due to repeated and transient anterior chest pain. Chest images revealed a moderate amount of pericardial fluid, slight bilateral pleural effusion, and infiltrations in both lower lung lobes. Colchicine treatment without antibiotics rapidly improved these symptoms and findings. Pericarditis, pleurisy and the response to colchicine indicated FMF. FMF should be considered as a causative disease of pulmonary infiltrations, especially if it occurs repeatedly.

Genetic Alteration May Proceed with a Histological Change in Glioblastoma: A Report from Initially Diagnosed as Nontumor Lesion Cases.

Despite recent signs of progress in diagnostic radiology, it is quite rare that a glioblastoma (GBM) is detected asymptomatically. We describe two patients with asymptomatic nonenhancing GBMs that were not diagnosed with neoplasia at first. The patients had brain scans as medical checkups, and incidentally lesions were detected. In both cases, surgical specimens histopathologically showed no evidence of neoplasia, whereas molecular genetic findings were isocitrate dehydrogenase (IDH)-wildtype, O6-methylguanine-DNA methyltransferase promoter (pMGMT) unmethylated, and telomerase reverse transcriptase (TERT) promoter mutated, which matched to GBM. One patient was observed without adjuvant therapy and the tumor recurred 7 months later. Reoperation was performed, and histopathologically GBM was confirmed with the same molecular diagnosis as the first surgical specimen. Another patient was carefully observed, and chemoradiotherapy was begun 6 months after the operation following the extension of the lesion. Eventually, because of disease progression, both patients deceased. We postulate that in each case, the tumor was not lower-grade glioma but corresponded to the early growth phase of GBM cells. Thus far, cases of malignant transformation from lower-grade glioma or asymptomatic GBM with typical histologic features are reported. Nevertheless, to the best of our knowledge, no such case of nonenhancing, nonhistologically confirmed GBM was reported. We conjecture these cases shed light on the yet unknown natural history of GBM. GBM can take the form of radiological nonenhancing and histological nonneoplastic fashion before typical morphology. Molecular genetic analysis can diagnose atypical preceding GBM, and we recommend early surgical removal and adjuvant treatment.

Early rebleeding of a foramen magnum dural arteriovenous fistula: A case report and review of the literature.

Foramen magnum dural arteriovenous fistula (FM-DAVF) is a subset of craniocervical junction arteriovenous fistulas. We report a rare case of FM-DAVF with early rebleeding and review the literature. A 50-year-old man experienced 3 episodes of intracranial bleeding from a vessel malformation in the acute stage. We identified an FM-DAVF, supplied by multiple feeding arteries (eg, left ascending pharyngeal artery) that drained into the straight sinus and left superior petrosal sinus. The draining vein had venous varices. We performed transarterial feeder embolization and surgical disconnection of the DAVF. Early rebleeding of FM-DAVF is rare. High-risk patients require risk assessment and appropriate treatment as soon as possible in the acute stage.

Inhibition of Gli2 suppresses tumorigenicity in glioblastoma stem cells derived from a de novo murine brain cancer model.

The prognosis of glioblastoma remains poor despite intensive research efforts. Glioblastoma stem cells (GSCs) contribute to tumorigenesis, invasive capacity, and therapy resistance. Leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5), a stem cell marker, is involved in the maintenance of GSCs, although the properties of Lgr5-positive GSCs remain unclear. Here, the Sleeping-Beauty transposon-induced glioblastoma model was used in Lgr5-GFP knock-in mice identify GFP-positive cells in neurosphere cultures from mouse glioblastoma tissues. Global gene expression analysis showed that Gli2 was highly expressed in GFP-positive GSCs. Gli2 knockdown using lentiviral-mediated shRNA downregulated Hedgehog-related and Wnt signaling pathway-related genes, including Lgr5; suppressed tumor cell proliferation and invasion capacity; and induced apoptosis. Pharmacological Gli inhibition with GANT61 suppressed tumor cell proliferation. Silencing Gli2 suppressed the tumorigenicity of GSCs in an orthotopic transplantation model in vivo. These findings suggest that Gli2 affects the Hedgehog and Wnt pathways and plays an important role in GSC maintenance, suggesting Gli2 as a therapeutic target for glioblastoma treatment.

Quantitative imaging of spontaneous neuromagnetic activity for assessing cerebral ischemia using sLORETA-qm.

To image cerebral neural activity in ischemic areas, we proposed a novel technique to analyze spontaneous neuromagnetic fields based on standardized low-resolution brain electromagnetic tomography modified for a quantifiable method (sLORETA-qm). Using a 160-channel whole-head-type magnetoencephalographic system, cerebral magnetic fields were obtained pre- and postoperatively from 5 patients with unilateral internal carotid artery occlusive disease and 16 age-matched healthy volunteers. For quantitative imaging, voxel-based time-averaged intensities of slow waves in 4 frequency bands (0.3-2 Hz, 2-4 Hz, 4-6 Hz and 6-8 Hz) were obtained by the proposed technique based on sLORETA-qm. Positron emission tomography with (15)O gas inhalation ((15)O-PET) was also performed in these patients to evaluate cerebral blood flow and metabolism. In all 5 patients, slow waves in every frequency band were distributed in the area of cerebrovascular insufficiency, as confirmed by (15)O-PET preoperatively. In 4 patients, slow-wave intensities in theta bands (4-6 Hz, 6-8 Hz) decreased postoperatively along with improvements in cerebral blood flow and metabolism, whereas delta bands (0.3-2 Hz, 2-4 Hz) showed no significant differences between pre- and postoperatively. One patient with deterioration of cerebral infarction after surgery showed marked increases in slow-wave intensities in delta bands (0.3-2 Hz, 2-4 Hz) postoperatively, with distribution close to the infarct region. The proposed quantitative imaging of spontaneous neuromagnetic fields enabled clear visualization and alternations of cerebral neural conditions in the ischemic area. This technique may offer a novel, non-invasive method for identifying cerebral ischemia, although further studies in a larger number of patients are warranted.