[Show abstract][Hide abstract] ABSTRACT: Infiltrative astrocytomas (IAs) represent a group of astrocytic gliomas ranging from low-grade to highly malignant, characterized by diffuse invasion of the brain parenchyma. When compared with their adult counterpart, pediatric IAs may be considered biologically distinct entities; nevertheless, similarly to those in adults they represent a complex oncologic challenge. The aim of this study was to investigate the diagnostic role, clinical contribution, and prognostic value of fused (18)F-3,4-dihydroxyphenylalanine ((18)F-DOPA) PET/MR images in pediatric supratentorial IAs.
Pediatric patients with supratentorial IAs involving at least 2 cerebral lobes, either newly diagnosed or with suspected disease progression, prospectively underwent (18)F-DOPA PET and conventional MR imaging, performed within 10 d of each other. (18)F-DOPA PET data were interpreted qualitatively and semiquantitatively, fusing images with MR images. PET scans were classified as positive if tumors identified on MR imaging exhibited tracer uptake above the level of the corresponding contralateral normal brain. Maximum standardized uptake values, tumor-to-normal contralateral tissue ratios, and tumor-to-normal striatum ratios were calculated for all tumors. Correlations between the degree and extent of (18)F-DOPA uptake, MR imaging tumor characteristics, and histologic results were investigated. The contribution of (18)F-DOPA PET/MR image fusion was considered relevant if it enabled one to select the most appropriate biopsy site, discriminate between disease progression and treatment-related changes, or influence treatment strategy. The patient's outcome was finally correlated with (18)F-DOPA uptake.
Thirteen patients (8 boys and 5 girls) were included (5 diffuse astrocytomas, 2 anaplastic astrocytomas, 5 gliomatosis cerebri, and 1 glioblastoma multiforme). The (18)F-DOPA uptake pattern was heterogeneous in all positive scans (9/13), revealing metabolic heterogeneities within each tumor. Significant differences in terms of (18)F-DOPA uptake were found between low- and high-grade lesions (P < 0.05). The diagnostic and therapeutic contribution of (18)F-DOPA PET/MR image fusion was relevant in 9 of 13 patients (69%). (18)F-DOPA uptake correlated significantly with progression-free survival (P = 0.004).
Our results indicate that (18)F-DOPA PET/MR image fusion may be a reliable imaging biomarker of pediatric IAs. Information gathered by this combined imaging approach can be readily transferred to the everyday practice and may help clinicians to better stratify patients with IAs, especially diffuse astrocytomas and gliomatosis cerebri, for diagnostic, therapeutic, and prognostic purposes.
Journal of Nuclear Medicine 03/2014; · 5.77 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Cavernous malformations (CM) are cerebral irradiation-related late complications. Little is known about their natural history and the pathogenetic role of concomitant chemotherapy. We present a retrospective, single-institution study of 108 children affected with medulloblastoma, ependymoma, or germinoma treated with radio- and chemotherapy. The frequency, clinical and radiological presentations, and outcomes were analyzed to investigate the relationship among radiation dose, associated chemotherapy, age, latency and localization of radiation-induced CM. 100 out of 108 children were treated with radiotherapy for primary brain tumor; 34 (27 with medulloblastoma and 7 with other histologies) out of 100 patients developed CM. No significant relationship was found between CM and gender (p = 0.70), age (p = 0.90), use of specific chemotherapy (standard versus high-dose, p = 0.38), methotrexate (p = 0.49), and radiation dose (p = 0.45). However, CM developed more frequently and earlier when radiotherapy was associated with methotrexate (70 % of cases). Radiation-induced CM prevailingly occurred in the cerebral hemispheres (p = 0.0001). Only 3 patients (9 %) were symptomatic with headache. Three patients underwent surgery for intra- or extra-lesional hemorrhage. CM was confirmed by histopathology for all 3 patients. The vast majority of radiation-induced CM is asymptomatic, and macro-hemorrhagic events occur rarely. Concomitant therapy with methotrexate seems to favor their development. We recommend observation for asymptomatic lesions, while surgery should be reserved to symptomatic growth or hemorrhage.
Journal of Neuro-Oncology 02/2014; · 3.12 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background
The aim of this study was to assess the objective response rate (ORR) of children and young adults with recurrent medulloblastoma/primitive neuroectodermal tumor (MB/PNET) treated with temozolomide (TMZ). The secondary purpose was to analyze the toxicity profile of TMZ when administered orally for 5 days in 3 divided daily doses every 28 days.Methods
Forty-two patients with recurrent MB/PNET, aged 21 years and younger, were recruited. Patients were treated with oral TMZ. Starting doses ranged from 120 to 200 mg/m(2)/day based on previous treatments. A craniospinal MRI was performed prior to the first cycle of TMZ and following every 2 cycles of treatment.ResultsMedian age was 10 years (range, 2-21 years). Forty of 42 patients were assessed for response and toxicity. The objective response rate was 42.5%: 6 patients achieved a complete response, 11 had a partial response, and 10 had stable disease. Progression-free survival rates for all patients at 6 and 12 months were 30% and 7.5%, respectively. Their median overall survival rates at 6 and 12 months were 42.5% and 17.5%, respectively. No major extrahematological effects or life-threatening events were reported. The most common grade 3/4 toxicity included thrombocytopenia (17.5%), neutropenia (7.5%), and anemia (2.5%).ConclusionsTMZ proved to be an effective agent in children and young adults with MB/PNET, heavily pre-treated, with a tolerable toxicity profile.
[Show abstract][Hide abstract] ABSTRACT: Atypical teratoid/rhabdoid tumor (AT/RT) of the Central Nervous System and malignant rhabdoid tumor of the kidney (MRTK) may present different response to chemotherapy and outcome.
We describe the case of an infant with multifocal rhabdoid tumor with different behaviour and response to treatment depending on the anatomic site.
[Show abstract][Hide abstract] ABSTRACT: We report on a 9-years-old patient with mild intellectual disability, facial dimorphisms, bilateral semicircular canal dysplasia, periventricular nodular heterotopias, bilateral hippocampal malrotation and abnormal cerebellar foliation, who developed mild motor impairment and gait disorder due to a pilocytic astrocytoma of the spinal cord. Array-CGH analysis revealed two paternal inherited chromosomal events: a 484.3 Kb duplication on chromosome 15q26.3 and a 247 Kb deletion on 22q11.23. Further, a second de novo 1.5 Mb deletion on 22q11.21 occurred. Chromosome 22 at q11.2 and chromosome 15 at q24q26 are considered unstable regions subjected to copy number variations, i.e. structural alterations of genome, mediated by low copy repeat sequences or segmental duplications. The link between some structural CNVs, which compromise fundamental processes controlling DNA stability, and genomic disorders suggest a plausible scenario for cancer predisposition. Evaluation of the genes at the breakpoints cannot account simultaneously for the phenotype and tumour development in this patient. The two paternal inherited CNVs arguably are not pathogenic and do not contribute to the clinical manifestations. Similarly, although the de novo large deletion at 22q11.21 overlaps with the Di George (DGS) critical region and results in haploinsufficiency of genes compromising critical processes for DNA stability, this case lacks several hallmarks of DGS.
[Show abstract][Hide abstract] ABSTRACT: Tuberous sclerosis complex is a genetic, multisystemic disorder characterized by circumscribed benign lesions (hamartomas) in several organs, including brain. This is the result of defects in the TSC1 and/or TSC2 tumor suppressor genes, encoding the hamartin-tuberin complex that inhibits the mammalian target of rapamycin pathway. Specific inhibitors of this pathway have been shown to reduce the volume of subependymal giant cell astrocytomas associated with tuberous sclerosis. Congenital lymphedema is rarely seen in association with tuberous sclerosis, with only a few reported cases. Although this association can be coincidental, the dysgenetic lymphatic system can represent a hamartia as a consequence of gene mutation. We describe a child with congenital lymphedema in tuberous sclerosis and associated subependymal giant cell astrocytoma who experienced lymphangitis under treatment with mammalian target of rapamycin inhibitors. Because our patient did not show worsening of lymphedema, congenital lymphedema does not seem to be a contraindication for this therapy.
Journal of child neurology 09/2013; · 1.59 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Paediatric low-grade gliomas (LGGs) encompass a heterogeneous set of tumours of different histologies, site of lesion, age and gender distribution, growth potential, morphological features, tendency to progression and clinical course. Among LGGs, Pilocytic astrocytomas (PAs) are the most common central nervous system (CNS) tumours in children. They are typically well-circumscribed, classified as grade I by the World Health Organization (WHO), but recurrence or progressive disease occurs in about 10-20% of cases. Despite radiological and neuropathological features deemed as classic are acknowledged, PA may present a bewildering variety of microscopic features. Indeed, tumours containing both neoplastic ganglion and astrocytic cells occur at a lower frequency.
Gene expression profiling on 40 primary LGGs including PAs and mixed glial-neuronal tumours comprising gangliogliomas (GG) and desmoplastic infantile gangliogliomas (DIG) using Affymetrix array platform was performed. A biologically validated machine learning workflow for the identification of microarray-based gene signatures was devised. The method is based on a sparsity inducing regularization algorithm l1l2 that selects relevant variables and takes into account their correlation. The most significant genetic signatures emerging from gene-chip analysis were confirmed and validated by qPCR.
We identified an expression signature composed by a biologically validated list of 15 genes, able to distinguish infratentorial from supratentorial LGGs. In addition, a specific molecular fingerprinting distinguishes the supratentorial PAs from those originating in the posterior fossa. Lastly, within supratentorial tumours, we also identified a gene expression pattern composed by neurogenesis, cell motility and cell growth genes which dichotomize mixed glial-neuronal tumours versus PAs. Our results reinforce previous observations about aberrant activation of the mitogen-activated protein kinase (MAPK) pathway in LGGs, but still point to an active involvement of TGF-beta signaling pathway in the PA development and pick out some hitherto unreported genes worthy of further investigation for the mixed glial-neuronal tumours.
The identification of a brain region-specific gene signature suggests that LGGs, with similar pathological features but located at different sites, may be distinguishable on the basis of cancer genetics. Molecular fingerprinting seems to be able to better sub-classify such morphologically heterogeneous tumours and it is remarkable that mixed glial-neuronal tumours are strikingly separated from PAs.
BMC Cancer 08/2013; 13(1):387. · 3.33 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background
We conducted a nonrandomized international study for intracranial germinoma that compared chemotherapy followed by local radiotherapy with reduced-dose craniospinal irradiation (CSI) alone, to determine whether the combined treatment regimen produced equivalent outcome and avoided irradiation beyond the primary tumor site(s).Methods
Patients with localized germinoma received either CSI or 2 courses of carboplatin and etoposide alternating with etoposide and ifosfamide, followed by local radiotherapy. Metastatic patients received CSI with focal boosts to primary tumor and metastatic sites, with the option to be preceded with chemotherapy.ResultsPatients with localized germinoma (n = 190) received either CSI alone (n = 125) or combined therapy (n = 65), demonstrating no differences in 5-year event-free or overall survival, but a difference in progression-free survival (0.97 ± 0.02 vs 0.88 ± 0.04; P = .04). Seven of 65 patients receiving combined treatment experienced relapse (6 with ventricular recurrence outside the primary radiotherapy field), and only 4 of 125 patients treated with CSI alone experienced relapse (all at the primary tumor site). Metastatic patients (n = 45) had 0.98 ± 0.023 event-free and overall survival.Conclusions
Localized germinoma can be treated with reduced dose CSI alone or with chemotherapy and reduced-field radiotherapy. The pattern of relapse suggests inclusion of ventricles in the radiation field. Reduced-dose craniospinal radiation alone is effective in metastatic disease.
[Show abstract][Hide abstract] ABSTRACT: Persons with Down syndrome (DS) uniquely have an increased frequency of leukemias but a decreased total frequency of solid tumors. The distribution and frequency of specific types of brain tumors have never been studied in DS. We evaluated the frequency of primary neural cell embryonal tumors and gliomas in a large international data set. The observed number of children with DS having a medulloblastoma, central nervous system primitive neuroectodermal tumor (CNS-PNET) or glial tumor was compared to the expected number. Data were collected from cancer registries or brain tumor registries in 13 countries of Europe, America, Asia and Oceania. The number of DS children with each category of tumor was treated as a Poisson variable with mean equal to 0.000884 times the total number of registrations in that category. Among 8,043 neural cell embryonal tumors (6,882 medulloblastomas and 1,161 CNS-PNETs), only one patient with medulloblastoma had DS, while 7.11 children in total and 6.08 with medulloblastoma were expected to have DS. (p 0.016 and 0.0066 respectively). Among 13,797 children with glioma, 10 had DS, whereas 12.2 were expected. Children with DS appear to be specifically protected against primary neural cell embryonal tumors of the CNS, whereas gliomas occur at the same frequency as in the general population. A similar protection against neuroblastoma, the principal extracranial neural cell embryonal tumor, has been observed in children with DS. Additional genetic material on the supernumerary chromosome 21 may protect against embryonal neural cell tumor development.
Journal of Neuro-Oncology 01/2013; · 3.12 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Microarray-based comparative genomic hybridization (array-CGH) led to the discovery of genetic abnormalities among patients with complex phenotype and normal karyotype. Also several apparently normal individuals have been found to be carriers of cryptic imbalances, hence the importance to perform parental investigations after the identification of a deletion/duplication in a proband. Here, we report the molecular cytogenetic characterization of two individuals in which the microdeletions/duplications present in their parents could have predisposed and facilitated the formation of de novo pathogenic different copy number variations (CNVs). In family 1, a 4-year-old girl had a de novo pathogenic 10.5 Mb duplication at 15q21.2q22.2, while her mother showed a 2.262 Mb deletion at 15q13.2q13.3; in family 2, a 9-year-old boy had a de novo 1.417 Mb deletion at 22q11.21 and a second paternal deletion of 247 Kb at 22q11.23 on the same chromosome 22. Chromosome 22 at band q11.2 and chromosome 15 at band q11q13 are considered unstable regions. We could hypothesize that 15q13.2q13.3 and 22q11.21 deletions in the two respective parents might have increased the risk of rearrangements in their children. This study highlights the difficulty to make genetic counseling and predict the phenotypic consequences in these situations.
PLoS ONE 01/2013; 8(3):e57910. · 3.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Glioneuronal tumours are a group of primary brain neoplasms of relatively recent acquisition in the World Health Organization (WHO) Classification of the Central Nervous System tumours. In diagnostic practice it is still possible to encounter glioneuronal tumours that cannot be placed into any of the well-defined WHO categories despite a growing list of entities. We have recently published four paediatric cases of diffuse leptomeningeal tumours that cannot be easily classified in the currently used CNS WHO classification, but which have histological and immunohistochemical criteria to be considered as glioneuronal tumours. The clinical, neuroradiological and pathological long-term follow-up of an unusual diffuse leptomeningeal glioneuronal tumour is presented herein.
[Show abstract][Hide abstract] ABSTRACT: Several molecular biomarkers have been suggested as predictors of outcome for pediatric ependymomas but deserve further validation in independent case series. We analyzed intracranial ependymomas belonging to a series of 60 patients prospectively treated according to the protocol sponsored by the Italian Association of Pediatric Hematology-Oncology. We used a tissue microarray to analyze nucleolin (NCL), cyclin-dependent kinase inhibitor 2A (CDKN2A), tumor protein 53 (TP53), and epidermal growth factor receptor (EGFR) by immunohistochemistry and by 1q gain by fluorescent in situ hybridization. The mRNA expression levels of EGFR, human telomerase reverse-transcriptase (HTERT), and Prominin 1 (PROM 1)/CD133 were evaluated by quantitative real-time PCR from cases with fresh-frozen tumor material available. Univariate and multivariate analyses of updated clinical data confirmed the prognostic significance of surgery (P < .01) and tumor grading (P < .05) for both relapse-free survival (RFS) and overall survival (OS). Among biomolecular markers, HTERT mRNA expression emerged with the strongest association with OS at multivariate analysis (hazard ratio [HR] = 9.9; P = .011); the 5-year OS was 84% versus 48% in the subgroups with HTERT median value <6 versus ≥6, respectively (P = .005). Five-year RFS was 46% versus 20% in the subgroups with low versus high NCL protein expression, respectively (P = .004), while multivariate Cox analyses gave suggestively high HRs for high versus low NCL (HR = 1.9; P = .090). The other genes tested were not significant at multivariate analyses, and genetic alterations of CDKN2A, TP53, EGFR, and HTERT loci were rare. The PROM1/CD133 cancer stem cell marker was strongly expressed at both RNA and protein levels in a substantial fraction of cases and was suggestively associated with a more indolent form of the disease. We conclude that NCL and HTERT represent the strongest prognostic biomarkers of RFS and OS, respectively, in our ependymoma case series.
[Show abstract][Hide abstract] ABSTRACT: Somatic mutations of the isocitrate dehydrogenase-1 gene (IDH1), most commonly resulting in replacement of arginine at position 132 by histidine (p.R132H), have been reported for WHO grade II and III diffuse gliomas and secondary glioblastomas. We investigated IDH1/2 mutations in a retrospective series of 165 pediatric brain tumors, including atypical teratoid/rhabdoid tumors (AT/RT) and choroid plexus tumors, which had not previously been investigated. Mutation analysis was performed by use of pyrosequencing and, additionally, data were validated for a cohort of 70 gliomas from among the series by use of the arrayed primer extension technique. We identified one tumor which harbored mutation of IDH1 at codon 132 and no alteration was identified in the matched-germline DNA. No IDH2 mutations were detected. Most noteworthy, the IDH1 mutant tumor was an anaplastic astrocytoma involving the cortex in the left frontal lobe which appeared seven years after radiation treatment for an extensive sellar/suprasellar craniopharyngioma. This anaplastic astrocytoma was regarded as secondary to radiation treatment because it seemed to originate within the irradiation field that received a dose varying from a maximum of 30.6 Gy of 4 MV X-rays down to very few Gy of lower-energy scattered radiation. In this work our observations agree with those in previous reports showing the rarity of IDH1/2 mutations in childhood tumors. The interesting identification of an IDH1 mutation in a radiation-induced secondary malignant glioma raises the likelihood that these types of tumor may develop IDH1/2 mutations. Thus, caution is needed when dealing with these tumors, and further genetic analysis is warranted.
Journal of Neuro-Oncology 07/2012; 109(3):477-84. · 3.12 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The Ras signaling pathway, consisting of mitogen-activated protein kinase (MAPK) and PI3K/AKT signaling, is a prominent oncogenic pathways in adult diffuse gliomas, but few studies have evaluated such pathways in pediatric malignant gliomas. We investigated by immunohistochemistry MAPK and AKT signaling in a series of 28 pediatric high-grade gliomas (WHO grade III and IV). We sought a possible association of phospho-ERK (p-ERK) and phospho-AKT (p-AKT) with expression of other proteins involved in the Ras pathway, that is, YKL40, epidermal growth factor receptor (EGFR), EGFR vIII and c-Met. Moreover we correlated the expression of p-ERK and p-AKT with prognosis. No cases showed expression for c-Met and EGFR, and only one case was positive for EGFR vIII. YKL-40 protein was expressed in 43% of cases. We detected expression of p-ERK and p-AKT in 61% and 57%, respectively, of pediatric high grade gliomas. Statistical analysis comparing the two groups in term of high and low p-ERK and p-AKT expression showed a trend toward worse overall survival in patients with high expression of p-AKT. The activation of ERK and AKT suggest a possible role of this protein in inducing activation of the Ras signaling pathway in pediatric high-grade gliomas. Moreover high levels of p-AKT are associated with worse overall survival.
[Show abstract][Hide abstract] ABSTRACT: Data regarding the epidemiology febrile neutropenia during chemotherapy for pediatric central nervous system neoplasia are scarce. Data retrieved from a prospective study performed from January 2002 to December 2004 at G.Gaslini Children Hospital, Genoa, Italy, where analyzed to evaluate proportions, rate for 1000 neutropenic days and etiology of fever in neutropenic children receiving gentle, standard, or peripheral blood stem cell transplant (PBSCT) therapy for central nervous system tumor. During the study duration, 243 periods of neutropenia (granulocyte count <1000/cmm), accounting for 3544 patient-days at risk, were documented in 62 children. A total of 72 febrile episodes were observed in 66 (27%) neutropenic periods, for a rate of 20.31. A primary febrile episode was observed in 10% of neutropenic periods after gentle chemotherapy, in 30% after standard chemotherapy, and in 48% after PBSCT (P<0.0001). The rate of primary febrile episodes was 6.19 after a gentle chemotherapy, 27.02 after standard treatment, and 31.02 after PBSCT (P<0.0001). In a multivariable regression model, the type of chemotherapy (gentle vs. standard and PBSCT) and the thresholds of granulocyte count at neutropenia onset (999-501/cmm and 500-101/cmm vs. ≤100/cmm) were the only factors significantly associated with the development of febrile neutropenia.
Journal of Pediatric Hematology/Oncology 10/2011; 33(7):e310-5. · 0.97 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Complete ependymoma resection ensures a better prognosis for children with this tumor, but the complete excision of infratentorial ependymomas involves serious risks. Second-look surgery for tumor remnants may be less harmful and enable complete removal. There is a potential, although still unclear, role for neoadjuvant chemotherapy in preparation for further surgery.
Since 1994, the authors have adopted two successive protocols for intracranial ependymoma, both including a phase of adjuvant chemotherapy for children with surgical tumor remnants with a plan for potential second-look surgery before radiotherapy.
In the first protocol, 9 of 63 children underwent further surgery, and 6 became tumor free with no additional sequelae. Their prognosis for progression-free survival and freedom from local relapse was comparable to that of children who were operated on only once. In the second protocol, efforts were made to achieve complete resection and 29 of 110 patients underwent reoperations: 9 after the first surgery, 17 after chemotherapy, and 3 soon after radiotherapy. Fourteen of the 29 patients became tumor free, 1 of them with worsening neurological symptoms. The outcome of the 66 patients who became tumor free after 1 operation was compared with that of the 14 who became tumor free after reoperation. The 3-year progression-free survival of the 66 patients compared with the 14 other patients was 71.4% ± 6.9% and 90% ± 9.5%, respectively; the 3-year freedom from local relapse was 84.7% ± 5.9% and 90% ± 9.5%, respectively; and the 3-year overall survival was 85.9% ± 5.4% and 87.5% ± 11.7%, respectively.
Second-look surgery proved feasible with no major morbidity, and results improved with time. Local tumor control was comparable in patients undergoing 1 or more resections.
Journal of Neurosurgery Pediatrics 09/2011; 8(3):246-50. · 1.63 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The protocols of the 1990s omitted or delayed irradiation, using upfront chemotherapy to spare the youngest children with ependymoma the sequelae of radiotherapy (RT). We treated 41 children under the age of 3 years with intracranial ependymoma between 1994 and 2003.
After surgery, chemotherapy was given as follows: regimen I with four blocks of vincristine, high-dose methotrexate 5 g/m(2), and cyclophosphamide 1.5 g/m(2) alternating with cisplatin 90 mg/m(2) plus VP16 450 mg/m(2) for 14 months; subsequently, regimen II was used: VEC (VCR, VP16 300 mg/m(2), and cyclophosphamide 3 g/m(2)) for 6 months. Radiotherapy was planned for residual tumor after the completion of chemotherapy or for progression.
We treated 23 boys and 18 girls who were a median 22 months old; 14 were given regimen I, 27 were given regimen II; 22 underwent complete resection, 19 had residual tumor. Ependymoma was Grade 2 in 25 patients and Grade 3 in 16; tumors were infratentorial in 37 patients and supratentorial in 4. One child had intracranial metastases; 29 had progressed locally after a median 9 months. Event-free survival was 26% at 3 and 5 years and 23% at 8 years. One child died of sepsis, and another developed a glioblastoma 72 months after RT. Progression-free survival was 27% at 3, 5, and 8 years, and overall survival was 48%, 37%, and 28% at 3, 5, and 8 years, respectively. Of the 13 survivors, 6 never received RT; their intellectual outcome did not differ significantly in those children than in those without RT.
Our results confirm poor rates of event-free survival and overall survival for up-front chemotherapy in infant ependymoma. No better neurocognitive outcome was demonstrated in the few survivors who never received RT.
International journal of radiation oncology, biology, physics 07/2011; 80(3):807-14. · 4.59 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Medulloblastoma (MB) is the most common malignant brain tumor of childhood. We have investigated for novel chromosomal imbalances and prognostic markers of pediatric MB. Forty MBs out of 64, were analyzed using high resolution prometaphase comparative genomic hybridization. Chromosome 10q26.1-q26.3 loss combined with 17q24.3-q25.3 gain and/or 7q34-q36.3 gain in tumors predicted poor patient's survival. A minimal deleted region of 14.12cM at 10q26.1-q26.3 was refined by LOH analysis. We propose a new prognostic marker for pediatric MB patient risk stratification based on the presence of 10q26.1-q26.3 loss plus 17q24.3-q25.3 gain and/or 7q34-q36.3 gain associations.
Cancer letters 06/2011; 308(2):215-24. · 4.86 Impact Factor