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 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.

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.

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.

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.

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.

[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.

Methods for Generating Vascularized Islet-Like Organoids Via Self-Condensation.

Despite the promise of emerging organoid-based approaches, building additional complexity, such as the vascular network, remains a major challenge toward regenerative therapy. Recently, we developed a complex organoid engineering method by "self-condensation," wherein mesenchymal cell-dependent contraction enables large-scale condensation from heterotypic multiple progenitors. Here, we describe the adaptation of this protocol for generating three-dimensional (3D) pancreatic condensates from dissociated ß cell lines (MIN6) together with blood vessel-forming progenitors. This protocol achieves 3D pancreatic islet-like organoid self-organization with endothelialized networks through mesenchymal stem cell-dependent contraction. Transplantation of pancreatic islet-like organoids treats diabetes in mice effectively. Given the donor shortage associated with clinical islet transplantation, our approach offers a promising alternative toward therapeutic organoid transplantation. © 2018 by John Wiley & Sons, Inc.

Self-Condensation Culture Enables Vascularization of Tissue Fragments for Efficient Therapeutic Transplantation.

Clinical transplantation of tissue fragments, including islets, faces a critical challenge because of a lack of effective strategies that ensure efficient engraftment through the timely integration of vascular networks. We recently developed a complex organoid engineering method by "self-condensation" culture based on mesenchymal cell-dependent contraction, thereby enabling dissociated heterotypic lineages including endothelial cells to self-organize in a spatiotemporal manner. Here, we report the successful adaptation of this method for generating complex tissues from diverse tissue fragments derived from various organs, including pancreatic islets. The self-condensation of human and mouse islets with endothelial cells not only promoted functionalization in culture but also massively improved post-transplant engraftment. Therapeutically, fulminant diabetic mice were more efficiently treated by a vascularized islet transplant compared with the conventional approach. Given the general limitations of post-transplant vascularization associated with 3D tissue-based therapy, our approach offers a promising means of enhancing efficacy in the context of therapeutic tissue transplantation.

Usefulness of 18F-fluorodeoxyglucose-Positron Emission Tomography in Comparison with Methionine-Positron Emission Tomography in Differentiating Solid Hemangioblastoma from Adult Cerebellar Tumors.

BACKGROUND AND PURPOSE: Among adults with posterior fossa tumors, an intraaxial location of the tumor is less common than an extraaxial location. Moreover, the differential diagnosis of a single cerebellar tumor in adults is sometimes difficult by conventional magnetic resonance imaging. We aimed to report the findings of positron emission tomography (PET) using 18F-fluorodeoxyglucose (FDG) and methionine in adult patients with intraaxial and solitary metastatic brain tumors. MATERIALS AND METHODS: FDG-PET was performed on 12 patients with posterior fossa tumors: 4 had solid hemangioblastoma (HB), 3 had primary central nervous system lymphomas, 1 had a glioblastoma, and 4 had single metastatic brain tumors (METs). Methionine-PET was performed on 9 patients except for 1 patient with a MET. The maximum standardized uptake value (SUVmax) of the tumor was measured and compared with pathologic findings. RESULTS: The SUVmax of FDG in HB was lower compared with that of other tumors (P = 0.001). On the other hand, the SUVmax of methionine in the HB cases was almost the same as that in other tumors (P = 0.07). CONCLUSION: FDG-PET was helpful in differentiating HBs from adult cerebellar tumors.

Monocyte chemoattractant protein 1 expression and proliferation in primary central nervous system lymphoma.

Whether the poor prognosis of primary central nervous system lymphoma (PCNSL) compared with systemic diffuse large B cell lymphoma (DLBCL) is attributable to the immune privilege of the intracerebral location or to intrinsic differences in the biological characteristics of two types of lymphoma remains unclear. Monocyte chemoattractant protein 1 (MCP-1) is essential to support tumor cell survival and growth, and the present study aimed to compare MCP-1 expression in PCNSL and peripheral DLBCL. The present study included 19 patients with PCNSL and 16 patients with DLBCL, all of whom had tissue diagnosis and lymphoma tissue samples available for analysis. Histology included immunohistochemistry using antibodies against a panel of lymphoma markers, antibodies specific to MCP-1, and antibodies specific to tumor-associated macrophages. MCP-1 expression was quantified using immunostaining scoring. RNA extraction and reverse transcription-quantitative polymerase chain reaction were used to determine MCP-1 mRNA expression. In addition, a human brain-derived lymphoma cell line, HKBML, was stimulated with MCP-1 and cell proliferation was measured by 5-bromo-2'-deoxyuridine incorporation. The expression levels of MCP-1 mRNA and MCP-1 protein were significantly increased in PCNSL compared with peripheral DLBCL. MCP-1 induced tyrosine phosphorylation of mitogen-activated protein kinase in HKBML cells, as analyzed by western blotting. The results of the present study indicated that MCP-1 expression in PCNSL promoted cell proliferation in an autocrine manner.

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.

Engineering pancreatic tissues from stem cells towards therapy.

Pancreatic islet transplantation is performed as a potential treatment for type 1 diabetes mellitus. However, this approach is significantly limited due to the critical shortage of islet sources. Recently, a number of publications have developed protocols for directed ß-cell differentiation of pluripotent cells, such as embryonic stem (ES) or induced pluripotent stem (iPS) cells. Decades of studies have led to the development of modified protocols that recapitulate molecular developmental cues by combining various growth factors and small molecules with improved efficiency. However, the later step of pancreatic differentiation into functional ß-cells has yet to be satisfactory in vitro, highlighting alternative approach by recapitulating spatiotemporal multicellular interaction in three-dimensional (3D) culture. Here, we summarize recent progress in the directed differentiation into pancreatic ß-cells with a focus on both two-dimensional (2D) and 3D differentiation settings. We also discuss the potential transplantation strategies in combination with current bioengineering approaches towards diabetes therapy.

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.

Usefulness of 11C-methionine positron emission tomography for detecting intracranial ameloblastic carcinoma: A case report.

Ameloblastic carcinoma, secondary type, is an extremely rare odontogenic malignant tumor. The present study reports the case of a 58-year-old male with ameloblastic carcinoma that extended into the intracranial space close to the internal carotid artery. Surgical excision was performed, as headaches were being caused via compression by the mass. Small remnants of the tumor remained surrounding the internal carotid artery following surgical resection. Although the remnant tissue was not detected on magnetic resonance imaging or 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET), it was clearly visualized on 11C-methionine PET in the early post-operative follow-up period. No neurological deficits were exhibited during the follow-up period, and 11C-methionine PET was able to detect the remnant lesion distribution in the intracranial space. The current study presents a rare case of ameloblastic carcinoma that extended into the intracranial space. In addition, several diagnostic imaging tools were compared in order to determine the most suitable imaging modality. At present, the patient is continuing a therapeutic course of radiation and evident mass reduction has been observed. However, the therapeutic effects are currently under consideration. To the best of our knowledge, this is the first study on the effectiveness of using 11C-methionine PET for detecting ameloblastic carcinoma with intracranial extension.