Epidemiological Study of Metastatic Brain Tumors in Miyazaki Prefecture: A Regional 10-year Survey in Southern Japan.

Advances in cancer treatment have improved the survival of patients with cancer, with a concomitant increase in the proportion of patients with metastatic brain tumors (MBTs). In this study, we used cancer registries established in Japan after 2016 and available patient data by organ in order to conduct an accurate epidemiological study. To the best of our knowledge, this is the first study to report on the detailed epidemiological data on MBT at the prefectural level in Japan using the Miyazaki Brain Tumor Database and Miyazaki Cancer Registry. This study included 425 new cases of MBTs diagnosed in Miyazaki Prefecture from 2007 to 2016. As per our findings, the most frequent primary tumor in Miyazaki Prefecture was found to be in the lung (49.4%), followed by colon/rectum/anus (9.4%) and breast (8.5%). Among patients with MBTs, 59.1% were males, a number closely similar to that of Japan, as shown in the Japanese Brain Tumor Registry (55.5%). The median age at diagnosis was 68 and 63 years in Miyazaki Prefecture and Japan, respectively. Although more patients were symptomatic in Miyazaki Prefecture than in Japan (88.5% vs. 15.5%), fewer patients opted for surgery (33.6% vs. 61.9%), probably because of their advanced age at diagnosis. As per the findings of this study, the annual incidence rate of new MBTs (i.e., ratio of the number of new cancer registrations to that of new MBT patients in Miyazaki Prefecture) was at 0.41%. The number of tumor sites in MBTs was independent of the total number of cancers per organ. Considering the expansion of cancer registries worldwide, including those on brain tumors, further epidemiological analysis of MBTs is deemed warranted.

T2-fluid-attenuated inversion recovery mismatch sign in lower grade gliomas: correlation with pathological and molecular findings.

After the new molecular-based classification was reported to be useful for predicting prognosis, the T2-fluid-attenuated inversion recovery (FLAIR) mismatch sign has gained interest as one of the promising methods for detecting lower grade gliomas (LGGs) with isocitrate dehydrogenase (IDH) mutations and chromosome 1p/19q non-codeletion (IDH mut-Noncodel) with high specificity. Although all institutions could use T2-FLAIR mismatch sign without any obstacles, this sign was not completely helpful because of its low sensitivity. In this study, we attempted to uncover the mechanism of T2-FLAIR mismatch sign for clarifying the cause of this sign's low sensitivity. Among 99 patients with LGGs, 22 were T2-FLAIR mismatch sign-positive (22%), and this sign as a marker of IDH mut-Noncodel showed a sensitivity of 55.6% and specificity of 96.8%. Via pathological analyses, we could provide evidence that not only microcystic changes but the enlarged intercellular space was associated with T2-FLAIR mismatch sign (p = 0.017). As per the molecular analyses, overexpression of mTOR-related genes (m-TOR, RICTOR) were detected as the molecular events correlated with T2-FLAIR mismatch sign (p = 0.020, 0.030. respectively). Taken together, we suggested that T2-FLAIR mismatch sign could pick up the IDH mut-Noncodel LGGs with enlarged intercellular space or that with overexpression of mTOR-related genes.

Delayed methotrexate elimination in a patient with primary central nervous system lymphoma: A case report.

WHAT IS KNOWN AND OBJECTIVE: Methotrexate (MTX) is an important agent for the treatment of primary central nervous system lymphomas (PCNSL) but needs to be given in big doses by intravenous infusions to achieve therapeutic concentrations in the cerebrospinal fluid. However, co-administration with many drugs may delay the excretion of MTX which may cause serious adverse effects if the serum concentration exceeds 0.1 µmol/L 72 h after an intravenous infusion. CASE SUMMARY: A 67-year-old Japanese female with PCNSL was treated with high-dose MTX-based chemotherapy. The serum MTX concentration 72 h post-infusion was 0.153 µmol/L when she was taking levofloxacin (LVFX) but <0.1 µmol/L 72 h after 4 subsequent infusions when she was not taking LVFX. She was given many other drugs but the timing of the short course of LVFX and the fact that ciprofloxacin also delays MTX excretion suggests that LVFX was the cause. WHAT IS NEW AND CONCLUSION: Co-administration of LVFX may delay the excretion of MTX. Therefore, serum concentrations of MTX should be monitored to help prevent and improve the management of potentially serious MTX drug-drug interaction.

Selection of surgical approach for cerebellar hemangioblastomas based on venous drainage patterns.

Cerebellar hemangioblastomas remain surgically challenging because of the narrow, deep surgical corridors and tumor hypervascularity. Various surgical approaches are used according to the location, but optimal approaches have not been established. We propose a system of surgical approaches based on the venous drainage systems to facilitate surgical planning and achieve acceptable neurological outcomes. Cerebellar hemangioblastomas were divided into five types based on the main drainage systems: suboccipital hemangioblastomas draining to the transverse sinus (TS) or torcula, tentorial hemangioblastomas draining to the tentorial sinus or straight sinus, petrosal hemangioblastomas draining to the superior petrosal sinus (SPS), quadrigeminal hemangioblastomas draining to the galenic system, and tonsillar hemangioblastomas draining to the TS or torcula in conjunction with jugular bulb or SPS. Microsurgical approaches and patient outcome were retrospectively reviewed according to this classification. This study included 17 patients who underwent 21 operations for resection of 19 cerebellar hemangioblastomas, classified into 9 suboccipital, 4 tentorial, 2 petrosal, 2 quadrigeminal, and 2 tonsillar. Standard suboccipital craniotomies were utilized for suboccipital hemangioblastomas, the occipital transtentorial approach (OTA), and supracerebellar infratentorial approach for tentorial hemangioblastomas, the retrosigmoid approach for petrosal hemangioblastomas, OTA for quadrigeminal hemangioblastomas, and midline suboccipital approach for tonsillar hemangioblastomas. Gross total resection was achieved in all patients except one. Two patients with large hemangioblastomas (tonsillar and quadrigeminal) required second-stage operation which finally achieved gross total removal. No single approach had a significantly higher incidence of postoperative neurological deficits. Selection of the optimum surgical approach for cerebellar hemangioblastomas was successful based on the main drainage systems. Understanding of tumor growth and extension with respect to the venous drainage system is critical to select the appropriate surgical approach.

High-resolution melting effectively pre-screens for TP53 mutations before direct sequencing in patients with diffuse glioma.

TP53 mutations are important molecular markers in diffuse astrocytic tumors and medulloblastomas. We examined the efficacy of a pre-screening method for high-resolution melting (HRM) analysis of TP53 mutation before direct sequencing using samples from patients with diffuse glioma. Surgical samples from 64 diffuse gliomas were classified based on the 2016 World Health Organization (WHO) histopathological grading system and the cIMPACT-NOW (consortium to inform molecular and practical approaches to CNS tumor taxonomy-not official WHO) update. TP53 mutations from exon 5 to exon 8 were assessed by direct sequencing. The results of HRM and p53 immunohistochemistry (IHC) analysis were compared by recording the sensitivity, specificity, and false negative and false positive rates. Direct sequencing detected TP53 mutations in 18 of 64 samples (28.1%): diffuse astrocytoma, IDH-mutant (n = 3); diffuse astrocytoma, IDH-wild type (n = 1); anaplastic astrocytoma, IDH-mutant (n = 3); anaplastic astrocytoma, IDH-wild type (n = 4); and glioblastoma, IDH-wild type (n = 7). A total of 22 mutations was detected in the 18 samples; 4 samples exhibited duplicate missense mutations. Sensitivity and specificity were 0.96 and 0.96, respectively, for HRM analysis; they were 0.89 and 0.52, respectively, for p53 IHC. Overall accuracy was 0.98 for HRM and 0.63 for IHC. HRM analysis is a good pre-screening method for the detection of TP53 mutation before direct sequencing.

[A Case of Anterior Cranial Fossa Dural Arteriovenous Fistula Involving Uncontrolled Seizures Diagnosed Based on Characteristic Findings on Arterial Spin-labeling Imaging].

We report a case of anterior cranial fossa dural arteriovenous fistula(ACF-DAVF)in a patient whose diagnosis was made according to characteristic findings on arterial spin labeling(ASL)MRI. CASE:A 68-year-old man was admitted to our hospital because of intractable epilepsy. Based on the initial MRI findings, an initial diagnosis of limbic encephalitis was made. Steroids and anticonvulsant drugs were administered;however, the seizures could not be controlled. A second MRI with ASL revealed abnormal vessel signals in the base segments of the left frontal and temporal lobes toward the basal vein of Rosenthal. Digital subtraction angiography(DSA)revealed an arteriovenous shunt in the left anterior cranial fossa, which drained toward the medial side of the left temporal lobe. A diagnosis of ACF-DAVF with status epilepticus was made, and the main drainer was cauterized. After the surgical procedure, the epilepsy was controlled with antiepileptic drugs, and postoperative MRI revealed obliteration of ACF-DAVF, disappearance of the high-intensity area on FLAIR sequences, and disappearance of the high-intensity signal area on ASL.

Differentiation between glioblastoma and solitary brain metastasis using neurite orientation dispersion and density imaging.

BACKGROUND AND PURPOSE: Neurite orientation dispersion and density imaging (NODDI) is a new technique that applies a three-diffusion-compartment biophysical model. We assessed the usefulness of NODDI for the differentiation of glioblastoma from solitary brain metastasis. METHODS: NODDI data were prospectively obtained on a 3T magnetic resonance imaging (MRI) scanner from patients with previously untreated, histopathologically confirmed glioblastoma (n = 9) or solitary brain metastasis (n = 6). Using the NODDI Matlab Toolbox, we generated maps of the intra-cellular, extra-cellular, and isotropic volume (VIC, VEC, VISO) fraction. Apparent diffusion coefficient - and fraction anisotropy maps were created from the diffusion data. On each map we manually drew a region of interest around the peritumoral signal-change (PSC) - and the enhancing solid area of the lesion. Differences between glioblastoma and metastatic lesions were assessed and the area under the receiver operating characteristic curve (AUC) was determined. RESULTS: On VEC maps the mean value of the PSC area was significantly higher for glioblastoma than metastasis (P < 0.05); on VISO maps it tended to be higher for metastasis than glioblastoma. There was no significant difference on the other maps. Among the 5 parameters, the VEC fraction in the PSC area showed the highest diagnostic performance. The VEC threshold value of ≥ 0.48 yielded 100% sensitivity, 83.3% specificity, and an AUC of 0.87 for differentiating between the two tumor types. CONCLUSIONS: NODDI compartment maps of the PSC area may help to differentiate between glioblastoma and solitary brain metastasis.

Detection of the KIAA1549-BRAF fusion gene in cells forming microvascular proliferations in pilocytic astrocytoma.

Microvascular proliferation (MVP), an aberrant vascular structure containing multilayered mitotically active endothelial- and smooth-muscle cells/pericytes, is a histopathological hallmark of glioblastoma multiforme (GBM). Although MVP tends to be associated with high-grade glioma, it has also been detected in WHO grade I pilocytic astrocytoma (PA). However, little is known about the mechanism underlying its formation. Using TP53 point mutations as a marker for tumor-derived cells, we earlier reported that MVP was partially converted from tumor cells via mesenchymal transition. In the current study we used the KIAA1549-BRAF fusion gene as a marker to assess whether MVPs in PA contained tumor-derived cells and/or phenotypically distinct tumor cells expressing vascular markers. cDNA synthesized from frozen tissue of six PA patients operated at our institute was analyzed to detect the KIAA1549-BRAF fusion gene by reverse transcription polymerase chain reaction (RT-PCR) assay. The breakpoint in the fusion gene was identified by long and accurate PCR (LA-PCR) and Sanger sequencing of genomic DNA. Distinct tumor cells and cellular components of MVP were obtained by laser microdissection. For the qualitative and quantitative detection of the KIAA1549-BRAF fusion gene we performed genomic and digital PCR assays. Fluorescence in situ hybridization (FISH) was used to assess gene fusion in cellular components of MVP. Samples from three PA patients harbored the KIAA1549 exon 15, BRAF exon 9 fusion gene. In two patient samples with abundant MVP, RT-PCR assay detected strong bands arising from the KIAA1549-BRAF fusion gene in both tumor cells and cellular components of MVP. Digital PCR showed that vis-à-vis tumor tissue, its relative expression in cellular components of MVP was 42% in one- and 76% in another sample. FISH revealed amplified signals in both tumor cells and cellular components of MVP indicative of tandem duplication. Our findings suggest that in patients with PA, some cellular components of MVP contained tumor derived cell and/or phenotypically distinct tumor cells expressing vascular markers.

Impact of PCR-based molecular analysis in daily diagnosis for the patient with gliomas.

The WHO2016 CNS update requires a combined histological and molecular assessment. To assess the major aberrations such as co-deletion of complete chromosome arms 1p and 19q (Co-del), isocitrate dehydrogenase and histone H3 mutations, direct sequencing, multiplex ligation-dependent probe amplification and/or FISH are methods considered to be "golden standard" in the community. However, these methods are expensive and complicated. The aim of this study is verification of the sensitivity of the simple PCR-based techniques for assessment of molecular information in daily diagnosis. We analyzed a total number of 80 patients with gliomas. FISH and PCR-based microsatellite analysis were compared for Co-del assessment. Direct sequencing and qPCR using hig-resolution melting (HRM) were compared for IDH and histone H3 mutations. The sensitivity and specificity of FISH were 0.71 and 0.79, respectively. FISH using a commercially available Vysis probe had a risk of high false-positive rate (0.25). For assessment of IDH1 mutations, the sensitivity and specificity of HRM were 1.0 and 0.96, respectively. For assessment of IDH2 and H3 mutations by HRM, both sensitivity and specificity were 1.0. We consider PCR-based molecular analysis to be a simple and accurate technique in daily diagnosis that is readily available for a small scientific facility.

MGMT promoter methylation in patients with glioblastoma: is methylation-sensitive high-resolution melting superior to methylation-sensitive polymerase chain reaction assay?

OBJECTIVE: The methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) gene promoter is a prognostic factor in adults with glioblastoma (GBM); it also yields information that is useful for clinical decision-making in elderly GBM patients. While pyrosequencing is the gold standard for the evaluation of the methylation status of MGMT, methylation-sensitive polymerase chain reaction (MS-PCR) assay continues to be used widely. Although MS-PCR results exhibited a good correlation with the prognosis of patients with GBM treated under the Stupp protocol, interpretation of the bands is based on subjective judgment, and the assay cannot be used to analyze heterogeneously methylated samples. We assessed whether methylation-sensitive high-resolution melting (MS-HRM) is an alternative to MS-PCR. METHODS: The authors prepared 3 primer sets that covered CpG 72­89 for MS-HRM analysis to determine the methylation levels of 6 human glioma cell lines. The results were validated by bisulfite sequencing of cloned alleles. The authors also subjected surgical samples from 75 GBM patients treated with temozolomide (TMZ) to MS-HRM to assess the MGMT methylation status and compared the findings with MS-PCR results using receiver operating characteristic (ROC), univariate, and multivariate analyses. RESULTS: There was a strong correlation between the methylation levels of the 6 glioma cell lines evaluated by MSHRM and by bisulfite sequencing; with primers 1 and 2, the correlation was significant (r = 0.959 and r = 0.960, respectively, p < 0.01). Based on log-rank analysis, MS-HRM was significantly better than MS-PCR for predicting progressionfree survival (PFS) and overall survival (OS) based on the methylation status of the MGMT promoter (PFS predicted by MS-HRM and MS-PCR = 0.00023 and 0.0035, respectively; OS = 0.00019 and 0.00028, respectively). ROC analysis showed that the area under the curve was larger with MS-HRM than with MS-PCR (PFS: 0.723 vs 0.635; OS: 0.716 vs 0.695). Based on multivariate Cox regression analysis, MS-HRM was significantly better than MS-PCR for predicting the treatment outcome (MS-HRM vs MS-PCR: PFS, p = 0.001 vs 0.207; OS, p = 0.013 vs 0.135). CONCLUSIONS: The authors' findings show that MS-HRM is superior to MS-PCR for the detection of MGMT promoter methylation. They suggest MS-HRM as an alternative to MS-PCR for assessing the prognosis of patients with GBM.

Genetic Factors Affecting Intraoperative 5-aminolevulinic Acid-induced Fluorescence of Diffuse Gliomas.

BACKGROUND: In patients operated for malignant glioma, 5-aminolevulinic acid (5-ALA)-induced fluorescence guidance is useful. However, we occasionally experience instances of non-visible fluorescence despite a histopathological diagnosis of high-grade glioma. We sought to identify factors that influence the intraoperative visualization of gliomas by their 5-ALA-induced fluorescence. PATIENTS AND METHODS: We reviewed data from 60 patients with astrocytic or oligodendroglial tumors who underwent tumor removal under 5-ALA-induced fluorescence guidance between January 2014 and December 2015. Their characteristics, preoperative magnetic resonance imaging (MRI) findings, histological diagnosis, and genetic profile were analyzed and univariate and multivariate statistical analyses were performed. RESULTS: In 42 patients (70%) we intraoperatively observed tumor 5-ALA fluorescence. They were 2 of 8 (25%) patients with World Health Organization (WHO) grade II, 9 of 17 (53%) with grade III, and 31 of 35 (89%) patients with grade IV gliomas. Univariate analysis revealed a statistically significant association between 5-ALA fluorescence and the isocitrate dehydrogenase 1 (IDH1) status, 1p19q loss of heterozygosity (LOH), the MIB-1 labeling index, and the tumor margin, -heterogeneity, and -contrast enhancement on MRI scans (p < 0.001, p = 0.003, p = 0.007, p = 0.046, p = 0.021, and p = 0.002, respectively). Multivariate analysis showed that the IDH1 status was the only independent, statistically significant factor related to 5-ALA fluorescence (p = 0.009). CONCLUSIONS: This study identified the IDH1 status as the factor with the most influence on the 5-ALA fluorescence of diffuse gliomas.

Eosinophilic meningitis triggered by implanted Gliadel wafers: case report.

Although carmustine (Gliadel) wafers improve local tumor control and extend the overall survival in patients with malignant glioma, adverse effects have been documented. The authors report the first case of eosinophilic meningitis triggered by the placement of Gliadel wafers. A 61-year-old man with a history of alimentary allergy and glioblastoma in the right frontal lobe underwent resection followed by the implantation of Gliadel wafers. Three weeks later he suffered the sudden onset of headache, vomiting, and progressive consciousness disturbance. Computed tomography revealed enlargement of the ventricular system and subdural space on the side of the tumor. His CSF leukocyte count increased up to 3990 cells/mm3; 95% of the cells were eosinophilic granulocytes (EGs), suggesting eosinophilic meningitis. Laboratory examination showed the patient to have various elevated allergy indicators. The administration of corticosteroids failed to improve his condition. Despite the insertion of a lumbar drain his symptoms failed to improve. He underwent a second surgical intervention to remove the Gliadel wafers. Histologically, EGs had assembled around the wafers. Eosinophilic infiltrate was present in the brain parenchyma around small vessels. After ventriculoperitoneal shunting his course was favorable. A drug lymphocyte stimulation test against the Gliadel wafers failed to demonstrate a positive reaction; polifeprosan, the wafer matrix without 1,3-bis(2-chloroethyl)-1-nitrosourea, yielded a positive reaction. These findings strongly suggest that although extremely rare, polifeprosan (the wafer matrix) can elicit an allergic reaction. When eosinophilic meningitis is suspected after the implantation of Gliadel wafers, their immediate removal should be considered.

[The Usefulness of Strain Elastography for Determining Liver Fibrosis Stage in Chronic Viral Hepatitis: An Analysis Using Tissue Doppler Imaging with Manual Compression].

BACKGROUND/AIM: Accurate determination of the stage of liver fibrosis is an essential component in choice of treatment and assessment of cancer risk in patients with chronic viral hepatitis. The aim of this study was to evaluate the usefulness of strain elastography based on tissue Doppler imaging for liver fibrosis in chronic viral hepatitis. METHODS: A total of 37 patients with chronic viral hepatitis and 8 healthy volunteers were enrolled. Strain value was measured by using a conventional ultrasound machine that included strain imaging technolo- gy. Strain elastography was performed at the right subcostal area with manual compression. Liver fibrosis stages were assessed by using liver biopsy and compared with strain values. Diagnostic performance of the strain value for fibrosis stage 4, cirrhosis, was determined by performing a receiver-operating characteristics (ROC) curve analysis. RESULTS: Twenty-seven patients were positive for HCV RNA, 9 were positive for HBs antigen, and 1 was positive for both (Fibrosis stage F1, n=11; F2, n=7; F3, n=15; F4, n=4). The strain value of F3 and F4 was 0.066±0.02 and 0.042±0.011, respectively. These strain Values were significantly lower compared to those of healthy volunteers (0.112 ±0.018) (P< 0.05). Using a cutoff value of 0.042, the area under ROC curve was 0.88 for the diagnosis of F4. The sensitivity, specificity, positive predictive value, and negative predictive value were 75%, 92%, 50%, and 94%, respectively. CONCLUSIONS: Strain elastography based on tissue Doppler imaging with manual compression appears to be a useful tool to diagnose cirrhosis in patients with chronic viral hepatitis. [Original].