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Torsten Pietsch - One of the best experts on this subject based on the ideXlab platform.

  • met t992i mutation in a case of Ependymoblastoma embryonal tumour with multilayered rosettes
    Journal of Clinical Pathology, 2014
    Co-Authors: Marco Gessi, Halil Demir, Tobias Goschzik, Torsten Pietsch
    Abstract:

    Ependymoblastoma/embryonal tumour with multilayered rosettes (EPBL-ETMR) represents a distinct entity among primitive neuroectodermal tumours of the central nervous system (CNS).1 ,2 They are genetically characterised by the presence of a focal 19q13.42 amplification associated with upregulation of the oncogenic miRNA cluster C19MC.1 ,2 To date, no mutations in tyrosine kinase receptor genes have been reported in these tumours. We describe a MET T992I mutation in an EPBL-ETMR affecting a 2-year-old female patient. An MRI examination revealed a large supratentorial tumour with areas of haemorrhages and cystic features. The tumour presented at histological level with the typical EPBL-ETMR features showing highly cellular areas besides a neuropil-like matrix where several multilayered rosettes could be detected (figure 1A). As expected, the tumour was partially MAP2C (Sigma, St Louis, USA), diffuse LIN28A (Cell Signaling Technology, Danvers, USA), and focally S100-protein (Dako, Hamburg, Germany)-positive. The proliferation index, evaluated with an antibody against Ki67-Antigen (MIB-1, Dako), reached a value of 25% of stained tumour cell nuclei. Despite chemotherapy, the patient suffered …

  • Ependymoblastoma of the brainstem mri findings and differential diagnosis
    Pediatric Blood & Cancer, 2014
    Co-Authors: Johannes Nowak, Carolin Seidel, Carsten Friedrich, Stefan Rutkowski, Torsten Pietsch, Katja Von Hoff, Monika Warmuthmetz
    Abstract:

    Ependymoblastoma (EBL) is a rare malignant CNS tumor of early childhood, listed as a subgroup of primitive neuroectodermal tumors (PNET) in the 2007 WHO Classification of Tumours of the Central Nervous System. Histologically, EBL can be defined by multilayered, mitotically active “ependymoblastic” rosettes with central lumen as a histological hallmark. The prognosis seems to be far inferior to other embryonal CNS tumors, and known clinical and MRI characteristics of EBL are based on scattered case reports. We present and discuss two uncommon cases of histopathologically confirmed Ependymoblastoma that both seem to originate from the brainstem. Pediatr Blood Cancer 2014;61:1132–1134. © 2014 Wiley Periodicals, Inc.

  • outcome of 11 children with Ependymoblastoma treated within the prospective hit trials between 1991 and 2006
    Journal of Neuro-oncology, 2011
    Co-Authors: Katja Von Hoff, Monika Warmuthmetz, Nicolas U Gerber, Andre O Von Bueren, Wiebke Treulieb, Torsten Pietsch
    Abstract:

    Ependymoblastoma is a rare malignant brain tumor of early childhood. Data on clinical behavior and optimal treatment strategies are scarce. We report on 11 consecutively treated children with centrally confirmed diagnosis of CNS Ependymoblastoma, registered between February 1994 and October 2006 to the prospective GPOH-HIT multicenter brain tumor trials, and treated by multimodal regimens. Median age at diagnosis was 3.5 years (range, 1.8–5.6 years), and the median follow-up of survivors was 5.9 years (range, 2.2–12.7 years). Initial stage was M0 in 9, and M0/1 (no cerebrospinal fluid examination done) in 2 patients. Gross-total tumor resection was achieved in 7 patients, incomplete resection in 4 patients. Further primary therapy included chemotherapy in all patients, craniospinal radiotherapy in 5 patients and high-dose chemotherapy in 2 patients. Tumor response to chemotherapy was observed in 1 of 4 evaluable patients. Tumor progression occurred in 7 patients after a median time of 5.0 months (range, 2.5–19.2 months). Five-year progression-free survival was 36.4% (±14.5%), 5-year overall survival 30.3% (±15.9%). Of 4 survivors, 3 had gross-total tumor resection, and all were treated by either craniospinal radiotherapy and/or high-dose chemotherapy with autologous blood stem cell rescue. Prognosis of children with Ependymoblastoma is poor, but sustained remissions have been achieved after multimodal treatment. Considerable diagnostic discrepancies between local and central pathologists underscore the importance of central review. Further studies are needed to improve survival of children with this rare malignant central nervous system tumor.

Johannes Nowak - One of the best experts on this subject based on the ideXlab platform.

  • mri characteristics of Ependymoblastoma results from 22 centrally reviewed cases
    American Journal of Neuroradiology, 2014
    Co-Authors: Johannes Nowak, Carolin Seidel, F Berg, T Pietsch, Carsten Friedrich, K Von Hoff, Stefan Rutkowski, M Warmuthmetz
    Abstract:

    BACKGROUND AND PURPOSE: Ependymoblastoma is a malignant embryonal tumor that develops in early childhood and has a dismal prognosis. Categorized by the World Health Organization as a subgroup of CNS-primitive neuroectodermal tumor, Ependymoblastoma is histologically defined by “ependymoblastic rosettes.” Because it is so rare, little is known about specific MR imaging characteristics of Ependymoblastoma. We systematically analyzed and discussed MR imaging features of Ependymoblastoma in a series of 22 consecutive patients. MATERIALS AND METHODS: Ependymoblastoma cases were obtained from the database of the German multicenter HIT trials between 2002 and 2013. All cases within this study were centrally reviewed for histopathology, MR imaging findings, and multimodal therapy. For systematic analysis of initial MR imaging scans at diagnosis, we applied standardized criteria for reference image evaluation of pediatric brain tumors. RESULTS: Ependymoblastomas are large tumors with well-defined tumor margins, iso- to hyperintense signal on T2WI, and diffusion restriction. Contrast enhancement is variable, with a tendency to mild or moderate enhancement. Subarachnoid spread is common in Ependymoblastoma but can be absent initially. There was a male preponderance (1.75:1 ratio) for Ependymoblastoma in our cohort. Mean age at diagnosis was 2.1 years. CONCLUSIONS: With this study, we add the largest case collection to the limited published database of MR imaging findings in Ependymoblastoma, together with epidemiologic data. However, future studies are needed to systematically compare MR imaging findings of Ependymoblastoma with other CNS-primitive neuroectodermal tumors and ependymoma, to delineate imaging criteria that might help distinguish these pediatric brain tumor entities.

  • Ependymoblastoma of the brainstem mri findings and differential diagnosis
    Pediatric Blood & Cancer, 2014
    Co-Authors: Johannes Nowak, Carolin Seidel, Carsten Friedrich, Stefan Rutkowski, Torsten Pietsch, Katja Von Hoff, Monika Warmuthmetz
    Abstract:

    Ependymoblastoma (EBL) is a rare malignant CNS tumor of early childhood, listed as a subgroup of primitive neuroectodermal tumors (PNET) in the 2007 WHO Classification of Tumours of the Central Nervous System. Histologically, EBL can be defined by multilayered, mitotically active “ependymoblastic” rosettes with central lumen as a histological hallmark. The prognosis seems to be far inferior to other embryonal CNS tumors, and known clinical and MRI characteristics of EBL are based on scattered case reports. We present and discuss two uncommon cases of histopathologically confirmed Ependymoblastoma that both seem to originate from the brainstem. Pediatr Blood Cancer 2014;61:1132–1134. © 2014 Wiley Periodicals, Inc.

Luigi Aloe - One of the best experts on this subject based on the ideXlab platform.

A Antonelli - One of the best experts on this subject based on the ideXlab platform.

  • tumor suppressor proteins are differentially affected in human Ependymoblastoma and medulloblastoma cells exposed to nerve growth factor
    Cancer Investigation, 2007
    Co-Authors: A Antonelli, L Lenzi, Akira Nakagawara, T Osaki, Antonio Chiaretti, Luigi Aloe
    Abstract:

    The aim of our study was to investigate the role of nerve growth factor (NGF) on the expression of the p73 protein in human Ependymoblastoma (EP) and medulloblastoma (MB) cells. It was found that NGF exposure on MB cells blocks proliferation, as well as on EP cells and induces overexpression of p73. NGF reduces the number of cells and promotes the expression of TrkA of these neoplastic cells. Moreover, NGF plus cisplatin treatment reduces the cytotoxic effect of cisplatin. These observations indicate that NGF by interfering with mechanisms associated with cells proliferation and survival might induce the differentiation event through TrkA pathways.

  • In vitro human Ependymoblastoma cells differentiate after exposure to nerve growth factor
    Journal of Neurocytology, 2004
    Co-Authors: A Antonelli, A. Chiaretti, M. Piastra, E. Vigneti, L. Aloe
    Abstract:

    Nerve Growth Factor (NGF) has a prominent action on immature crest-derived nerve cells and on differentiation and survival of neurons in central and peripheral nervous system. NGF is produced by a variety of neuronal and non-neuronal cells, including neoplastic cells. Its role in tumor cells is largely unknown and controversial. The aim of the present study was to investigate the effect of NGF on brain neoplastic cells using primary cultures from Ependymoblastoma (EP) tissue. Human EP tissues were cultured to obtain in vitro cells and their structural, biochemical, and molecular responses to NGF were investigated. The results showed that under basal conditions, human EP cells are characterized by low presence of high-affinity NGF-receptors. Time-course and dose-response studies revealed that EP cells undergo differentiation after exposure to NGF. Our findings showed that in human EP cells, NGF exerts a marked action on differentiation rather than proliferation.

Monika Warmuthmetz - One of the best experts on this subject based on the ideXlab platform.

  • Ependymoblastoma of the brainstem mri findings and differential diagnosis
    Pediatric Blood & Cancer, 2014
    Co-Authors: Johannes Nowak, Carolin Seidel, Carsten Friedrich, Stefan Rutkowski, Torsten Pietsch, Katja Von Hoff, Monika Warmuthmetz
    Abstract:

    Ependymoblastoma (EBL) is a rare malignant CNS tumor of early childhood, listed as a subgroup of primitive neuroectodermal tumors (PNET) in the 2007 WHO Classification of Tumours of the Central Nervous System. Histologically, EBL can be defined by multilayered, mitotically active “ependymoblastic” rosettes with central lumen as a histological hallmark. The prognosis seems to be far inferior to other embryonal CNS tumors, and known clinical and MRI characteristics of EBL are based on scattered case reports. We present and discuss two uncommon cases of histopathologically confirmed Ependymoblastoma that both seem to originate from the brainstem. Pediatr Blood Cancer 2014;61:1132–1134. © 2014 Wiley Periodicals, Inc.

  • outcome of 11 children with Ependymoblastoma treated within the prospective hit trials between 1991 and 2006
    Journal of Neuro-oncology, 2011
    Co-Authors: Katja Von Hoff, Monika Warmuthmetz, Nicolas U Gerber, Andre O Von Bueren, Wiebke Treulieb, Torsten Pietsch
    Abstract:

    Ependymoblastoma is a rare malignant brain tumor of early childhood. Data on clinical behavior and optimal treatment strategies are scarce. We report on 11 consecutively treated children with centrally confirmed diagnosis of CNS Ependymoblastoma, registered between February 1994 and October 2006 to the prospective GPOH-HIT multicenter brain tumor trials, and treated by multimodal regimens. Median age at diagnosis was 3.5 years (range, 1.8–5.6 years), and the median follow-up of survivors was 5.9 years (range, 2.2–12.7 years). Initial stage was M0 in 9, and M0/1 (no cerebrospinal fluid examination done) in 2 patients. Gross-total tumor resection was achieved in 7 patients, incomplete resection in 4 patients. Further primary therapy included chemotherapy in all patients, craniospinal radiotherapy in 5 patients and high-dose chemotherapy in 2 patients. Tumor response to chemotherapy was observed in 1 of 4 evaluable patients. Tumor progression occurred in 7 patients after a median time of 5.0 months (range, 2.5–19.2 months). Five-year progression-free survival was 36.4% (±14.5%), 5-year overall survival 30.3% (±15.9%). Of 4 survivors, 3 had gross-total tumor resection, and all were treated by either craniospinal radiotherapy and/or high-dose chemotherapy with autologous blood stem cell rescue. Prognosis of children with Ependymoblastoma is poor, but sustained remissions have been achieved after multimodal treatment. Considerable diagnostic discrepancies between local and central pathologists underscore the importance of central review. Further studies are needed to improve survival of children with this rare malignant central nervous system tumor.