Brain and Spinal Tumors Originating from the Germ Line Cells.

Primary central nervous system germ cell tumors (CNS GCTs) are part of the GCTs in children and adults. This tumor entity presents with geographic variation, age, and sex predilection. There are two age peaks of incidence distribution at the first few months of life and in adolescence. CNS GCTs are heterogeneous in histopathological subtypes, locations, and tumor marker (AFP, ß-hCG) secretions. In the WHO CNS tumor classification, GCTS are classified as germinoma and nongerminomatous GCT (NGGCT) with different subtypes (including teratoma). Excluding mature teratoma, the remaining NGGCTs are malignant (NGMGCT). In teratoma, growing teratoma syndrome and teratoma with somatic-type malignancy should be highlighted. The common intracranial locations are pineal region, neurohypophysis (NH), bifocal pineal-NH, basal ganglia, and cerebral ventricle. Above 50% of intracranial GCTs (IGCTs) present obstructive hydrocephalus. Spinal tumors are rare. Age, locations, hydrocephalus, and serum/CSF titer of ß-hCG correlate with clinical manifestations. Delayed diagnosis is common in tumors arising in neurohypophysis, bifocal, and basal ganglia resulting in the increasing of physical dysfunction and hormonal deficits. Staging work-up includes CSF cytology for tumor cells and contrast-enhanced MRI of brain and spine for macroscopic metastasis before treatment commences. The therapeutic approach of CNS GCTs integrates locations, histopathology, staging, tumor marker level, and therapeutic classification. Treatment strategies include surgical biopsy/excision, chemotherapy, radiotherapy (single or combination). Secreting tumors with consistent imaging may not require histopathological diagnosis. Primary germinomas are highly radiosensitive and the therapeutic aim is to maintain high survival rate using optimal radiotherapy regimen with/without chemotherapy combination. Primary NGNGCTs are less radiosensitive. The therapeutic aim is to increase survival utilizing more intensive chemotherapy and radiotherapy. The negative prognostic factors are residue disease at the end of treatment and serum or CSF AFP level >1000 ng/mL at diagnosis. In refractory or recurrent NMGGCTs, besides high-dose chemotherapy, new therapy is necessary. Molecular profiling and analysis help for translational research. Survivors of pediatric brain tumors frequently experience cancer-related cognitive dysfunction, physical disability, pituitary hormone deficiency, and other CNS complications after cranial radiotherapy. Continuous surveillance and assessment may lead to improvements in treatment protocols, transdisciplinary interventions, after-treatment rehabilitation, and quality of life.

Regulation of extracellular and intracellular prolactin on cell proliferation and survival rate through GHR/JAK2/STAT3 pathway in NSCLC.

Styrene increases serum prolactin (PRL) concentration. Hyperprolactinemia is associated with poor prognosis in lung cancer patients, but the mechanism of PRL action is unclear. The aims of this study were to (i) investigate the mechanism of PRL-action receptor in NSCLC cells (ii) measure whether PRL was secreted by NSCLC cells and its stimulatory mechanism in vitro and in vivo. We found that cell proliferation was increased after treatment of a pharmacological dose of PRL in A549 cells, which through up regulation of growth hormone receptor (GHR) and downstream of JAK2/STAT3/VEGF pathway. All NSCLC cells in the present study secreted PRL and expressed GHR, but not PRLR. Inhibition of GHR protein level led to decrease the PRL-induced cell proliferation. PRL was detected in NSCLC cells culture medium. Knockdown of intracellular PRL downregulated JAK2/STAT3 protein activities and GHR and VEGF protein levels. Furthermore, knockdown of intracellular PRL reduced the cell proliferation and the ability of colony-forming. In lung cancer tissues, PRL, GHR and VEGF levels were higher in the tumor tissues than in normal tissues and the protein expressions of these three proteins are positively correlated, respectively. High expression levels of both PRL and GHR cause a poor survival rate in lung cancer patients. Taken together, our results suggested that extracellular and intracellular PRL were involved in cell proliferation through GHR. Combination of in vitro and in vivo results, GHR and PRL are important targets for suppressing NSCLC cell proliferation, which might improve the survival rate in NSCLC patients.

Upregulation of Protein Synthesis and Proteasome Degradation Confers Sensitivity to Proteasome Inhibitor Bortezomib in Myc-Atypical Teratoid/Rhabdoid Tumors.

Atypical teratoid rhabdoid tumors (ATRTs) are among the most malignant brain tumors in early childhood and remain incurable. Myc-ATRT is driven by the Myc oncogene, which directly controls the intracellular protein synthesis rate. Proteasome inhibitor bortezomib (BTZ) was approved by the Food and Drug Administration as a primary treatment for multiple myeloma. This study aimed to determine whether the upregulation of protein synthesis and proteasome degradation in Myc-ATRTs increases tumor cell sensitivity to BTZ. We performed differential gene expression and gene set enrichment analysis on matched primary and recurrent patient-derived xenograft (PDX) samples from an infant with ATRT. Concomitant upregulation of the Myc pathway, protein synthesis and proteasome degradation were identified in recurrent ATRTs. Additionally, we found the proteasome-encoding genes were highly expressed in ATRTs compared with in normal brain tissues, correlated with the malignancy of tumor cells and were essential for tumor cell survival. BTZ inhibited proliferation and induced apoptosis through the accumulation of p53 in three human Myc-ATRT cell lines (PDX-derived tumor cell line Re1-P6, BT-12 and CHLA-266). Furthermore, BTZ inhibited tumor growth and prolonged survival in Myc-ATRT orthotopic xenograft mice. Our findings suggest that BTZ may be a promising targeted therapy for Myc-ATRTs.

Molecular-Clinical Correlation in Pediatric Medulloblastoma: A Cohort Series Study of 52 Cases in Taiwan.

In 2016, a project was initiated in Taiwan to adopt molecular diagnosis of childhood medulloblastoma (MB). In this study, we aimed to identify a molecular-clinical correlation and somatic mutation for exploring risk-adapted treatment, drug targets, and potential genetic predisposition. In total, 52 frozen tumor tissues of childhood MBs were collected. RNA sequencing (RNA-Seq) and DNA methylation array data were generated. Molecular subgrouping and clinical correlation analysis were performed. An adjusted Heidelberg risk stratification scheme was defined for updated clinical risk stratification. We selected 51 genes for somatic variant calling using RNA-Seq data. Relevant clinical findings were defined. Potential drug targets and genetic predispositions were explored. Four core molecular subgroups (WNT, SHH, Group 3, and Group 4) were identified. Genetic backgrounds of metastasis at diagnosis and extent of tumor resection were observed. The adjusted Heidelberg scheme showed its applicability. Potential drug targets were detected in the pathways of DNA damage response. Among the 10 patients with SHH MBs analyzed using whole exome sequencing studies, five patients exhibited potential genetic predispositions and four patients had relevant germline mutations. The findings of this study provide valuable information for updated risk adapted treatment and personalized care of childhood MBs in our cohort series and in Taiwan.

Loss of BCAT1 Expression is a Sensitive Marker for IDH-Mutant Diffuse Glioma.

BACKGROUND: IDH mutation is an important prognostic factor of diffuse astrocytomas. Although the majority of IDH mutations could be identified by immunohistochemical (IHC) stain for R132H-mutant IDH1, DNA sequencing would be required for IHC negative cases to determine their IDH mutation status. This approach is not cost-effective for tumors with low IDH mutation rates. OBJECTIVE: To investigate whether BCAT1 could be used as a surrogate marker for IDH mutations, because BCAT1 is an enzyme related to IDH genes. METHODS: A group of 120 anaplastic astrocytomas were immunostained for BCAT1, ATRX, and R132H-mutant IDH1. Staining results correlated with the results of DNA sequencing of IDH1/IDH2. RESULTS: DNA sequencing showed IDH1/2 mutations in 50.8% of cases of which 73.8% had IDH1 R132H mutation. Several IDH1 noncodon 132 mutations, ie, G97D, S122N, G123E, I130K, and G131S, which had uncertain prognostic significance, were identified. IHC stain for R132H-mutant IDH1 identified 93.3% of IDH1 R132H mutations and 70.5% of all IDH mutations. BCAT1 loss was seen in 65.8% of cases, its sensitivity to identify IDH mutations was 96.7%. The sensitivity reached 100% for IDH1 codon 132 and IDH2 codon 172 mutations. CONCLUSION: Positive BCAT1 stain could be used to exclude diffuse gliomas with IDH1 codon 132 and IDH2 codon 172 mutations. Selecting cases with negative BCAT1 and R132H-mutant IDH1 staining for DNA sequencing of IDH1/2 genes could improve the cost-effectiveness of detecting IDH mutations particularly in tumors with low IDH mutation rates, and confine the need of 1p/19q assay in IDH-mutant tumors.

Irradiation-Induced Secondary Tumors following Pediatric Central Nervous System Tumors: Experiences of a Single Institute in Taiwan (1975-2013).

PURPOSE: Complications can occur following a prolonged latency period after radiation therapy for cancer, and this is a growing concern because secondary tumors are potentially fatal. Few studies have examined secondary tumors in patients who received radiation therapy as children. METHODS AND MATERIALS: This retrospective study examined 1697 pediatric patients with central nervous system tumors who received treatment at Taipei Veterans General Hospital from January 1, 1975, to December 31, 2013. Secondary tumors developed in 27 of 681 patients who received cranial irradiation. Overall survival was estimated using the Kaplan-Meier method, and the significance of differences was determined by the log-rank test. RESULTS: The overall cumulative incidence of secondary tumors at 25 years was 3.96%, and there were similar numbers of male patients (n = 16) and female patients (n = 11). The mean age at diagnosis was 8.8 years (range, 3-16.5 years), the median dose of cranial irradiation was 52.5 Gy (mean, 53.4 Gy), the mean latency period was 14.6 years (range, 2-33 years), and the mean age at diagnosis of a secondary tumor was 23.1 years. The secondary tumors were mainly meningiomas (n = 13), sarcomas (n = 7), and high-grade gliomas (n = 6), and the mean latency periods were 19.66, 8.00, and 10.83 years, respectively. The overall survival rate from these secondary tumors was significantly different (P < .05). Age at irradiation of <7 years and craniospinal irradiation significantly increased the risk of a secondary tumor (P < .05). Secondary tumors developed in 11 of 128 patients (8.6%) with primary medulloblastomas, which was higher than the overall cumulative incidence. CONCLUSIONS: Clinicians should consider the increased risk of secondary tumors in long-term cancer survivors who received craniospinal irradiation as children. Using a selective dose de-escalation strategy or deferring radiation therapy for young patients at highest risk of secondary cancers should be studied.

The MGMT promoter single-nucleotide polymorphism rs1625649 had prognostic impact on patients with MGMT methylated glioblastoma.

Promoter methylation is the most significant mechanism to regulate O6-methylguanine-DNA-methyltransferase (MGMT) expression. Single-nucleotide polymorphisms (SNPs) in the MGMT promoter region may also play a role. The aim of this study was to evaluate the clinical significance of SNPs in the MGMT promoter region of glioblastoma. Genomic DNAs from 118 glioblastomas were collected for polymerase chain reaction (PCR) amplification. Sanger sequencing was used to sequence the MGMT promoter region to detect SNPs. The results were correlated with MGMT status and patient survival. Rs1625649 was the only polymorphic SNP located at the MGMT promoter region in 37.5% of glioblastomas. Homozygous rs1625649 (AA genotype) was correlated with a higher MGMT methylation level and a lower protein expression, but the result was not statistically significant. In patients with MGMT methylated glioblastoma, cases with homozygous rs1625649 (AA genotype) were significantly associated with a lack of MGMT protein expression and a better progression-free survival (PFS) than the cases with wild type rs1625649 (CC genotype) or heterozygous rs1625649 (CA genotype). The survival impact was significant in multivariate analyses. In conclusion, the MGMT promoter homozygous rs1625649 (AA genotype) was found to correlate with a better PFS in patients with MGMT methylated glioblastoma.

Detection of human cytomegalovirus in glioblastoma among Taiwanese subjects.

The relationship between human cytomegalovirus (HCMV) and glioblastoma (GBM) has been debated for more than a decade. We investigated the presence of HCMV genes, RNA and protein in GBMs and their relationships with tumor progression. Results of quantitative PCR for HCMV UL73, nested PCR for HCMV UL144, in situ hybridization (ISH) for RNA transcript, and immunohistochemistry (IHC) for protein expression and their relationship to the prognosis of 116 patients with GBM were evaluated. Nine (7.8%) cases revealed a low concentration of HCMV UL73, and only 2 of the 9 (1.7%) cases showed consistent positivity on repeat PCR testing. HCMV UL144, ISH and IHC assays were all negative. The HCMV UL73 positive cases did not show significant difference in the clinicopathological characters including age, gender, Karnofsky performance status, extent of resection, bevacizumab treatment, isocitrate dehydrogenase 1 mutation, O6-methylguanine-DNA-methyltranferase status and Ki67 labeling index, and did not reveal prognostic significance. As only one HCMV gene was detected at low concentration in 7.8% of GBMs and there was no evidence of transcription, protein expression or prognostic impact, we cannot conclude a relationship between HCMV and GBM in Taiwanese patients.

Large cell/anaplastic medulloblastoma is associated with poor prognosis-a retrospective analysis at a single institute.

PURPOSE: Medulloblastoma (MB) is the most commonly occurring malignant pediatric brain tumor worldwide. However, a recent study found that the treatment outcomes in those with high-risk disease receiving conventional treatment were suboptimal. This study aimed to assess outcomes and treatment strategies for specific histologic subtypes of pediatric MB. METHODS: A total of 114 pediatric patients (age < 20 years) diagnosed with MB between March 1998 and August 2011 were retrospectively reviewed; 52 that were treated with surgery followed by adjuvant radiotherapy (RT) and chemotherapy (CHT) were included. RESULTS: The 5-year overall survival (OS) and relapse-free survival (RFS) rates were 73 and 69%, respectively. Median time to relapse was 17 months with a median survival time of 6 months after relapse. Patients of average risk had a better 5-year OS rate compared with high-risk patients (p = 0.027). The 5-year RFS of high-risk patients was lower compared with average risk (p = 0.038). A greater proportion of patients with large cell/anaplastic (LC/A) MB had recurrence than classic MB with 5-year RFS rate of 34 and 76%, respectively (p = 0.001), and OS rate of 56 and 76%, respectively (p = 0.04). CONCLUSION: High-risk group and histology of LC/A were the most significant factors associated with worse OS and RFS. Patients with LC/A-MB had higher relapse rates and worse survival than those with classic MB. LC/A-MB carries a high risk for recurrence and should be treated with the more aggressive strategies.

Comparative Assessment of 4 Methods to Analyze MGMT Status in a Series of 121 Glioblastoma Patients.

The O-methylguanine-DNA-methyltranferase (MGMT) status is a powerful predictor of response to temozolomide for newly diagnosed glioblastoma (GBM) patients, and it is commonly assessed by immunohistochemistry (IHC), methylation-specific polymerase chain reaction (MSP), quantitative real-time MSP (qMSP), and/or pyrosequencing (PSQ). This study was to compare their predictive power of prognosis in 121 newly diagnosed GBM patients using multivariate Cox regression with bootstrapping. MGMT status tested by IHC, MSP, qMSP, or PSQ all showed significant correlation with the progression-free survival and overall survival of GBM patients. The predictive power of IHC for progression-free survival and overall survival was lower than those of the methylation assays, but their differences were not significant. Performing additional methylation assay, especially PSQ, could better predict the prognosis of patients with IHC- tumors. MGMT status tested by IHC, MSP, qMSP, or PSQ all showed prognostic significance. An additional MGMT methylation assay, of which PSQ appeared to be the best, could improve the predictive power for GBM patients with MGMT IHC- tumors.

Thyroid transcription factor-1 distinguishes subependymal giant cell astrocytoma from its mimics and supports its cell origin from the progenitor cells in the medial ganglionic eminence.

Subependymal giant cell astrocytoma is a benign brain tumor mostly associated with tuberous sclerosis complex. However, it may be misinterpreted as other high-grade brain tumors due to the presence of large tumor cells with conspicuous pleomorphism and occasional atypical features, such as tumor necrosis and endothelial proliferation. In this study, we first investigated thyroid transcription factor-1 (TTF-1) expression in a large series of subependymal giant cell astrocytomas and other histologic and locational mimics to validate the diagnostic utility of this marker. We then examined TTF-1 expression in non-neoplastic brain tissue to determine the cell origin of subependymal giant cell astrocytoma. Twenty-four subependymal giant cell astrocytoma specimens were subjected to tissue microarray construction. For comparison, a selection of tumors, including histologic mimics (21 gemistocytic astrocytomas and 24 gangliogliomas), tumors predominantly occurring at the ventricular system (50 ependymomas, 19 neurocytomas, and 7 subependymomas), and 134 astrocytomas (3 pleomorphic xanthoastrocytomas, 45 diffuse astrocytomas, 46 anaplastic astrocytomas, and 40 glioblastomas) were used. Immunohistochemical stain for TTF-1 was positive in all 24 subependymal giant cell astrocytomas, whereas negative in all astrocytomas, gangliogliomas, ependymomas, and subependymomas. Neurocytomas were positive for TTF-1 in 4/19 (21%) of cases using clone 8G7G3/1 and in 9/19 (47%) of cases using clone SPT24. In the three fetal brains that we examined, TTF-1 expression was seen in the medial ganglionic eminence, a transient fetal structure between the caudate nucleus and the thalami. There was no BRAFV600E mutation identified by direct sequencing in the 20 subependymal giant cell astrocytomas that we studied. In conclusion, TTF-1 is a useful marker in distinguishing subependymal giant cell astrocytoma from its mimics. Expression of TTF-1 in the fetal medial ganglionic eminence indicates that subependymal giant cell astrocytoma may originate from the progenitor cells in this region.

Clinical considerations and surgical approaches for low-grade gliomas in deep hemispheric locations: thalamic lesions.

BACKGROUND: Tumors with epicenter in the thalamus occur in about 4 % of pediatric brain tumors. The histological diagnosis is mainly gliomas. Among them, low-grade glioma (LGG) constituted of a significant entity of the tumors (Cuccia et al., Childs Nerv Syst 13:514-521, 1997; Puget et al., J Neurosurg 106:354-362, 2007; Bernstein et al., J Neurosurg 61:649-656, 1984; Bilginer et al., Childs Nerv Syst 30:1493-1498, 2014). Since Kelly's report in 1989, >90 % resection of thalamic tumors were achieved in reported series (Ozek and Ture, Childs Nerv Syst 18:450-6, 2002; Villarejo et al., Childs Nerv Syst 10:111-114, 1994; Moshel et al., Neurosurgery 61:66-75, 2007; Albright, J Neurosurg 100(5 Suppl Pediatrics): 468-472, 2004; Kelly, Neurosurgery 25:185-195, 1989; Drake et al., Neurosurgery 29: 27-33, 1991). MATERIALS AND METHODS: Sixty-nine cases of thalamic tumors in children were retrospectively reviewed. There were 25 cases of LGGs. We analyzed our experience and correlated it with reported series. RESULTS: Summing up of 4 reported series and the present series, there were 267 cases of thalamic tumors in children. Among these tumors, 107 (40.1 %) were LGGs and 91 (34.1 %) were low-grade astrocytomas (LGAs). In the present series, all of the 25 LGGs were LGAs that consisted of 11 pilocytic astrocytomas (PAs) and 14 diffuse astrocytomas (DAs). Six cases received biopsy sampling only. The remaining 19 cases received different degrees of surgical resection via several approaches. Radical (>90 %) resection was achieved better in PAs comparing with DAs. There was no operative mortality. Two patients had increased neurological deficits. In a mean follow-up period of 11.9 years, three patients died of tumor progression and one patient died of anaplastic change. The 5- and 10-year overall survival (OS) was 87.1 and 87.1 %, respectively. CONCLUSION: Thalamic LGGs are mainly LGAs and are indolent. The rate of >90 % resection was relatively low in the present series. By applying contemporary diagnostic MRI studies, surgical facilities, and appropriate approaches in selective cases, we may try maximum neuroprotective radical (>90 %) resection.

Computed tomography and magnetic resonance imaging findings of intraorbital granular cell tumor (Abrikossoff's tumor): a case report.

BACKGROUND: Granular cell tumors are rare neoplasms which can occur in any part of the body. Granular cell tumors of the orbit account for only 3 % of all granular cell tumor cases. Computed tomography and magnetic resonance imaging of the orbit have proven useful for diagnosing orbital tumors. However, the rarity of intraorbital granular cell tumors poses a significant diagnostic challenge for both clinicians and radiologists. CASE PRESENTATION: We report a case of a 37-year-old Chinese woman with a rare intraocular granular cell tumor of her right eye presenting with diplopia, proptosis, and restriction of ocular movement. Preoperative orbital computed tomography and magnetic resonance imaging with contrast enhancement revealed an enhancing solid, ovoid, well-demarcated, retrobulbar nodule. In addition, magnetic resonance imaging features included an intraorbital tumor which was isointense relative to gray matter on T1-weighted imaging and hypointense on T2-weighted imaging. No diffusion restriction of water was noted on either axial diffusion-weighted images or apparent diffusion coefficient maps. Both computed tomography and magnetic resonance imaging features suggested an intraorbital hemangioma. However, postoperative pathology (together with immunohistochemistry) identified an intraorbital granular cell tumor. CONCLUSIONS: When intraorbital T2 hypointensity and free diffusion of water are observed on magnetic resonance imaging, a granular cell tumor should be included in the differential diagnosis of an intraocular tumor.

Downregulation of miR-137 and miR-6500-3p promotes cell proliferation in pediatric high-grade gliomas.

Pediatric high-grade gliomas (pHGGs) are aggressive brain tumors affecting children, and outcomes have remained dismal, even with access to new multimodal therapies. In this study, we compared the miRNomes and transcriptomes of pediatric low- (pLGGs) and high-grade gliomas (pHGGs) using small RNA sequencing (smRNA-Seq) and gene expression microarray, respectively. Through integrated bioinformatics analyses and experimental validation, we identified miR-137 and miR-6500-3p as significantly downregulated in pHGGs. miR-137 or miR-6500-3p overexpression reduced cell proliferation in two pHGG cell lines, SF188 and UW479. CENPE, KIF14 and NCAPG levels were significantly higher in pHGGs than pLGGs, and were direct targets of miR-137 or miR-6500-3p. Furthermore, knockdown of CENPE, KIF14 or NCAPG combined with temozolomide treatment resulted in a combined suppressive effect on pHGG cell proliferation. In summary, our results identify novel mRNA/miRNA interactions that contribute to pediatric glioma malignancy and represent potential targets for the development of new therapeutic strategies.

Factors affecting survival of medulloblastoma in children: the changing concept of management.

Medulloblastoma (MB) is a type of malignant tumor arising only in the cerebellum that was first defined by Cushing and Bailey in 1920s. In this review paper, we trace the evolution of risk stratification and the correlated changing concept of management in the past years. Outcome analysis of the hospital series of the Taipei Veterans General Hospital, Cheng Hsin General Hospital, and Taipei Medical University Hospital was performed to correlate prognostic indicators with reported studies. The purpose is to provide clues for age-specific and risk-adjusted optimal, effective, but beneficial and protective treatment strategies of these tumors in children.

Can mixed pure hepatocellular carcinoma and germinoma arise together in the brain?

Intracranial germ-cell tumors (GCTs) represent 10-15% of all pediatric brain tumors in East Asia. There is a wide histopathological spectrum of intracranial GCTs. Germinomas and nongerminomatous GCTs are the two major classifications. It is difficult to distinguish different subtypes of intracranial GCTs based solely on imaging studies, however, some tumor markers, such as α-fetoprotein or ß-human chorionic gonadotropin, are helpful for diagnosis. In this study we present the case of a 13-year-old girl with an intracranial mixed GCT containing a hepatocellular carcinoma and germinoma without a primary liver tumor. Based on this unique pathological diagnosis, a series of treatments were applied, including surgery for gross tumor removal, adjuvant radiotherapy, and chemotherapy. Long-term follow up indicates fair disease control.

Integrated genomics has identified a new AT/RT-like yet INI1-positive brain tumor subtype among primary pediatric embryonal tumors.

BACKGROUND: Pediatric embryonal brain tumors (PEBTs), which encompass medulloblastoma (MB), primitive neuroectodermal tumor (PNET) and atypical teratoid/rhabdoid tumor (AT/RT), are the second most prevalent pediatric brain tumor type. AT/RT is highly malignant and is often misdiagnosed as MB or PNET. The distinction of AT/RT from PNET/MB is of clinical significance because the survival rate of patients with AT/RT is substantially lower. The diagnosis of AT/RT relies primarily on morphologic assessment and immunohistochemical (IHC) staining for a few known markers such as the lack of INI1 protein expression. However, in our clinical practice we have observed several AT/RT-like tumors, that fulfilled histopathological and all other biomarker criteria for a diagnosis of AT/RT, yet retained INI1 immunoreactivity. Recent studies have also reported preserved INI1 immunoreactivity among certain diagnosed AT/RTs. It is therefore necessary to re-evaluate INI1(+), AT/RT-like cases. METHOD: Sanger sequencing, array CGH and mRNA microarray analyses were performed on PEBT samples to investigate their genomic landscapes. RESULTS: Patients with AT/RT and those with INI(+) AT/RT-like tumors showed a similar survival rate, and global array CGH analysis and INI1 gene sequencing showed no differential chromosomal aberration markers between INI1(-) AT/RT and INI(+) AT/RT-like cases. We did not misdiagnose MBs or PNETs as AT/RT-like tumors because transcriptome profiling revealed that not only did AT/RT and INI(+) AT/RT-like cases express distinct mRNA and microRNA profiles, their gene expression patterns were different from those of MBs and PNETs. The most similar transcriptome profile to that of AT/RTs was the profile of embryonic stem cells. However; the transcriptome profile of INI1(+) AT/RT-like tumors was more similar to that of somatic neural stem cells, while the profile of MBs was closer to that of fetal brain tissue. Novel biomarkers were identified that can be used to distinguish INI1(-) AT/RTs, INI1(+) AT/RT-like cases and MBs. CONCLUSION: Our studies revealed a novel INI1(+) ATRT-like subtype among Taiwanese pediatric patients. New diagnostic biomarkers, as well as new therapeutic tactics, can be developed according to the transcriptome data that were unveiled in this work.

Treatment results and prognostic factors for intracranial nongerminomatous germ cell tumors: single institute experience.

PURPOSE: This study aimed to evaluate the treatment of intracranial nongerminomatous germ cell tumors (NGGCT) and to identify the prognostic factors for survival. METHODS: Thirty-nine patients with nondisseminated NGGCTs, excluding those with pure mature teratomas, were treated between January 1985 and December 2010. Twenty-four patients received gross total or partial removal, 11 had excision biopsies, and 4 had no surgery. Radiotherapy was given postoperatively or definitively with a median tumor bed dose of 54 Gy (range 30-54) with or without craniospinal irradiation. All patients received ten cycles of adjuvant chemotherapy, vinblastine, bleomycin, etoposide, and cisplatin after radiotherapy, except for one with mixed anaplastic astrocytoma component who received oral temozolomide. Survival and prognostic factors were estimated by the Kaplan-Meier method and log-rank tests, respectively. RESULTS: After a median follow-up of 77.7 months (range 14-336), the 6-year overall survival (OS) and progression-free survival (PFS) were 74.4 and 79.5 %, respectively. Inferior PFS was associated with lesions in the suprasellar region (p = 0.017), poor pathological features (p = 0.048), and with poor image (p < 0.0001) and tumor marker (TM) response (p = 0.003) to irradiation. Decreased OS was associated with lesions in the suprasellar region (p = 0.026) and with poor image (p < 0.0001) and TM response (p = 0.027) to irradiation. Neither the extent of surgery nor the radiation field was found to significantly influence survival. CONCLUSIONS: By our multimodality approach, patients achieved comparable outcomes. Other than poor pathological features, patients with poor responses to radiotherapy are prone to early recurrence and inferior survival. These patients should be focused for more intensive adjuvant treatment.

Prognosis of glioblastoma with faint MGMT methylation-specific PCR product.

Methylation-specific polymerase chain reaction (MSP) for the promoter methylation status of O(6)-methylguanine-DNA-methyltranferase (MGMT) gene theoretically provides a positive or negative result. However, the faint MSP product is difficult to interpret. The aim of this study was to evaluate the significance of faint MSP product in glioblastoma (GBM). Critical concentrations of methylated control DNA, i.e., 100, 1, 0.5 and 0 % were run parallel with 116 newly diagnosed GBMs in order to standardize the interpretation and to distinguish positive (+), equivocal (±), and negative (-; unmethylated) results. Cases with the faint MSP product and its intensity between those of 1 and 0.5 % DNA controls were considered equivocal (±). MGMT methylation quantifications were also determined by quantitative real-time MSP (qMSP) and pyrosequencing (PSQ), and protein expression was detected by immunohistochemistry. There were significant correlations between MSP and all the aforementioned studies. The concordance rates between the MSP+ and qMSP+ cases, as well as the MSP- and qMSP- cases were 100 %, and the MSP± cases comprised 76.5 % of qMSP+ cases and 23.5 % of qMSP- cases. PSQ study showed that heterogeneous methylation was more frequently encountered in the MSP± cases. Multivariate analyses disclosed that although the overall survival of the MSP± cases was indistinct from that of the MSP+ cases, its progression free survival was significantly worse and was indistinct from that of the MSP- cases. In conclusion, GBMs with faint MGMT MSP products should be distinguished from MSP+ cases as their behaviors were different.