Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Neuroectodermal Tumors”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources
PubMedDate not supplied

Primitive neuroectodermal tumor (PNET) of the brain diagnosed during pregnancy.

BACKGROUND: Brain tumors in pregnancy are extremely rare events. A case of a patient with primitive neuroectodermal tumor (PNET) of the brain diagnosed during the second half of pregnancy is reported. CASE REPORT: The first case of PNET of the brain diagnosed in a 26-year-old woman, gravida 1 para 0, in her 20th week of pregnancy is presented. The patient presented with headache, nausea and blurred vision. Magnetic resonance imaging revealed a large ill-defined tumoral mass in the left frontal cortex. Gross subtotal resection was achieved via a left frontal craniotomy. Pathological evaluation revealed histology and immuno-histochemistry consistent with the diagnosis of PNET. Adjuvant radiation therapy to the neurocranium was administered. Additionally, chemotherapy with Temodal 5 mg (Temozolomid) was initiated at 30 weeks of gestation. The patient delivered her baby via Cesarean section at 34 weeks of gestation. After delivery, external beam radiation to the craniospinal axis completed the therapy. The patient is currently being followed-up at the Department of Oncology University of Vienna Medical School, without any evidence of disease, 3 months after diagnosis. CONCLUSION: This case is the first reported description of a PNET in pregnancy. A brief discussion of this rare disease and its management in pregnancy is presented. The treatment options seem to be reduced in pregnant women and mainly depend on the patient's condition as well as the gestational age at presentation. In a multidisciplinary approach, an optimal therapy schedule should be assessed depending on these two parameters.

Adult↗
PubMedDate not supplied

High-dose chemotherapy with autologous stem cell rescue as first line of treatment in young children with medulloblastoma and supratentorial primitive neuroectodermal tumors.

In order to improve the dismal prognosis of patients younger than 4 years old with medulloblastoma and supratentorial primitive neuroectodermal tumors (stPNET) seven young children were treated with high-dose chemotherapy (HDCT) and autologous stem cell rescue in our center. All patients underwent surgical debulking and standard chemotherapy. None of them received irradiation. The HDCT included busulfan 16 mg/kg, orally over 4 days (from days -5 to -2) in 6 hourly divided doses, and melphalan at a dose of 140 mg/m2 given by intravenous infusion over 5 min on day -1. Three patients additionally received thiotepa 250 mg/m2 given by intravenous infusion daily over 2 days (from day -2 to -1) and two patients additionally received topotecan 2 mg/m2 given by intravenous infusion daily over 30 min for 5 days (from day -11 to -7). Patients' stem cells were mobilized with granulocyte colony-stimulating factor at a dose of 12 microg/kg twice daily subcutaneously for four consecutive days. Cryopreserved peripheral blood progenitor cells were reinfused 48 h after completion of chemotherapy. With a median follow-up of 21 months (range 5-64) five complete responses were observed; one patient had partial response and one had stable disease. There was no treatment-related mortality. The 2 year event-free survival was 71.43 +/- 17%. Therefore we conclude that HDCT as consolidation regimen may improve the cure rates in very young children with medulloblastoma/stPNET avoiding long-term sequelae of radiotherapy.

Antineoplastic Agents, Alkylating↗
PubMed1997

Primitive neuroectodermal tumor in a child with tuberous sclerosis.

The case of a 13-year-old boy with tuberous sclerosis and primitive neuroectodermal tumor of bone is presented. A pathogenetic association between these two entities is postulated, the unifying underlying mechanism being a maldevelopment of the neural crest, or neurocristopathy.

Adolescent↗
PubMed1995

Isochromosome 17q demonstrated by interphase fluorescence in situ hybridization in primitive neuroectodermal tumors of the central nervous system.

We previously reported an i(17q) as a non-random finding in childhood primitive neuroectodermal tumors (PNETs) of the central nervous system. In the present study, we describe a two-color interphase fluorescence in situ hybridization (FISH) assay for detection of chromosome 17 abnormalities in tumors. Thirty-four PNETs were analyzed by FISH with a series of chromosome 17-specific probes which map to 17p13.3-17q25. The results from the FISH assay were then compared to the karyotypes prepared from the tumors. Ten of the 34 cases demonstrated an i(17q) by FISH and standard cytogenetics. Two PNETs were shown to have an i(17q) by FISH alone, and three additional tumors had deletions of 17p. Thus, a total of 15 of 34 (44%) of the PNETs in this series had a deletion of 17p. This study confirms and extends our previous reports that an i(17q) is the most common cytogenetic abnormality in PNETs. The interphase FISH assay which we employed will have clinical utility for diagnosis of children with malignant brain tumors, and it may be used for identification of tumors with 17p deletions for molecular studies aimed at identifying disease genes.

Adolescent↗
PubMed2001

Extraaxial primitive neuroectodermal tumor mimicking a vestibular schwannoma: diagnostic and therapeutic difficulties. Report of two cases.

Extraaxial cerebellopontine angle (CPA) medulloblastomas and other primitive neuroectodermal tumors (PNETs) are rare tumors. The authors report on two patients with PNETs who presented with progressive audiovestibular symptoms. In each case magnetic resonance (MR) imaging revealed an extraaxial lesion that filled the internal auditory meatus and exhibited the neuroimaging features of a vestibular schwannoma (VS). No high signal intensity was apparent in either the brainstem or adjacent cerebellum on T2-weighted MR images. Surgery with maximum resection (total in one case and subtotal in the other) was performed, followed by craniospinal radiotherapy. One year postoperatively, both patients were free from tumor. A CPA PNET mimicking a VS is a rare entity, the diagnosis of which is important because its treatment differs dramatically from that of VS, including prescribed surgery followed by conventional craniospinal radiotherapy.

Adult↗
PubMed1999

Vasoactive intestinal peptide (VIP) and VIP receptors: gene expression and growth modulation in medulloblastoma and other central primitive neuroectodermal tumors of childhood.

Vasoactive intestinal peptide (VIP) is a neuromodulator and growth regulator in the developing nervous system. We analyzed 10 primitive neuroectodermal tumor (PNET) cell lines, 29 central PNET (cPNET) and 17 tumors of the Ewing's sarcoma/peripheral PNET family (ESFT) using reverse transcriptase-polymerase chain reaction (RT-PCR) and Southern hybridization. Each of the 10 cell lines and 86.2% of cPNET expressed mRNA for VIP receptor 1 (VIPR1) compared to 52.9% of ESFT. VIPR2 was expressed in 75.8% of cPNET, in 28.6% of ESFT and in all 10 cell lines. cPNET demonstrated high-affinity binding of 125I-VIP on quantitative autoradiography and in competitive binding assays. VIP inhibited tumor cell proliferation in a dose-dependent manner in 5 of 7 PNET cell lines. We conclude that VIPR1 and VIPR2 are highly expressed in cPNET and demonstrate that VIP is a growth modulator in these tumors.

Autoradiography↗
PubMed1994

Characterization of five new cell lines derived from human primitive neuroectodermal tumors of the central nervous system.

Medulloblastoma (MB) represents the most frequent malignant brain tumor of childhood but only a few cell lines and animal models of this primitive neuroectodermal tumor (PNET) have thus far been established. Using specific cell culture conditions, we were able to derive four human MB cell lines (MHH-MED-1-4) as well as a cell line from a spinal PNET (MHH-PNET-5). The four MB cell lines grew in suspension as floating cell aggregates or as slightly adherent cells. They consisted of undifferentiated cells that did not express markers of late neuronal or glial lineages such as neurofilaments or glial fibrillary acidic protein. They also lacked expression of major histocompatibility complex class I or II antigens on the cell surface. All four MB lines were positive for vimentin and neuron-specific enolase, whereas synaptophysin, neural cell adhesion molecule, galactocerebroside, GD2, GD3, and the A2B5 antigen were expressed inconsistently. In contrast, MHH-PNET-5 grew as adherent monolayer and expressed major histocompatibility complex class I antigen. By cytogenetic analysis, the lines were near diploid with clonal aberrations. The MB lines showed no losses of chromosome arm 17p by either cytogenetic or microsatellite analyses. The cell line MHH-MED-2 exhibited double minute chromosomes, amplification of the c-myc gene, and overexpression of c-myc mRNA and protein. N-myc, p53, and Rb protein expression were unaltered. All four continuously passaged MB cell lines and the MHH-PNET-5 line were xenotransplanted s.c. into athymic mice; three of four MB lines and the spinal PNET line gave rise to tumors. These cell lines will be useful tools for biological and preclinical studies on PNETs.

Animals↗
PubMed2003

Primitive neuroectodermal tumor (PNET) of the urinary bladder.

We report on the clinical, morphologic, immunohistochemical, ultrastructural, and molecular cytogenetic features of a primitive neuroectodermal tumor (PNET) primarily arising in the urinary bladder. An 81-year-old man presented with lymphedema of the lower extremities, fatigue, and urge incontinence. Radiographically, a tumor filling the entire cavity of the urinary bladder and extending into the pelvic and retroperitoneal tissue was noted. Histology of tumor biopsies showed a highly cellular, focally necrotic small round-cell tumor with numerous mitoses and occasional rosette-like structures. The tumor cells displayed significant immunoreactivity for neuron-specific enolase (NSE) and the MIC2 gene product (CD99). Dense-core granules were detectable by electron microscopy. A molecular cytogenetic analysis using comparative genomic hybridization (CGH) revealed gains of the chromosomes 3p, 6, 8q, 12, 17q, and 21q. The patient died two weeks after diagnosis. To the best of our knowledge, this is the fifth reported case of a PNET of the urinary bladder, and the first that includes a molecular cytogenetic analysis based on CGH.

12E7 Antigen↗
PubMed1992

Primitive neuroectodermal tumors after prophylactic central nervous system irradiation in children. Association with an activated K-ras gene.

Three patients had supratentorial malignant brain tumors 7 to 9 years after prophylactic central nervous system (CNS) treatment for acute lymphocytic leukemia or malignant T-cell lymphoma. Therapy was administered at the age of 3 to 8 years and included cranial irradiation (total dose, 1800 to 2400 cGy) and intrathecal methotrexate. The brain tumors had histologic and immunohistochemical features of primitive neuroectodermal tumors (PNET), including neuroblastic rosettes, rhythmic arrangement of tumor cells, and immunohistochemical expression of glial, and in one patient neuronal, marker proteins. Using polymerase chain reaction-mediated DNA amplification from paraffin-embedded tissues and subsequent DNA sequence analysis, an activating point mutation was detected in the K-ras protooncogene in one tumor. This mutation was a G to A transition in position 2 of codon 12, substituting aspartate (GAT) for glycine (GGT). This type of mutation has not been observed before in human brain tumors, but it is frequent in radiation-induced murine lymphomas. These observations suggest that PNET can be induced after completion of the embryonal and fetal development of the human CNS. Oncogene-activating point mutations may represent a pathogenetic mechanism involved in the genesis of radiation-induced brain tumors.

Aspartic Acid↗
PubMed2003

Primitive neuroectodermal tumor of the mandible: report of a rare case.

We describe what we believe is only the second reported case of primitive neuroectodermal tumor of the mandible. Our patient was successfully treated initially with surgery and adjuvant radiation and chemotherapy, but 18 months later she developed a fatal pulmonary metastasis. Although this tumor is aggressive and prone to recurrence and metastasis, early intervention might improve the prognosis in affected patients. In patients with unresectable disease, radiation and chemotherapy might have palliative value.

Adult↗
PubMed2001

[Primary neuroectodermal tumor (PNET) of the kidney: 26 cases. Current status of its diagnosis and treatment].

OBJECTIVE: To report a case of primitive neuroectodermal tumor (PNET) of the kidney and review the literature and the 25 cases previously reported as PNET. METHODS: A 39-year-old man who consulted for nephric colic is described. Ultrasound evaluation disclosed a mass arising from the left kidney. The clinical, radiological and pathologic features, treatment and differential diagnosis of small cell tumors are discussed, as well as the important role of immunohistochemical techniques (positive staining with O13 or 12E7 antibodies) and cytogenetic analysis [a characteristic chromosomal translocation t(11;22) (q24;q12) or variant translocation, such as t(21;22) (q22;q12), may be detected by fluorescence in situ hybridization (FISH) or polymerase chain reaction-reverse transcriptase (PCR-RT)]. RESULTS: Survival of our patient was 20 months. Only three of the 25 previously reported cases had a longer survival: 60, 48 and 24 months. Mean survival was 10 months. 95.24% of the cases were positive for NSE. Immunostaining (CD99) was performed in 16 patients and was found to be positive in all cases. Cytogenetic and molecular analyses were performed in 11 cases; PCR-RT was negative in two, as well as in the case described herein. CONCLUSIONS: PNET is a highly aggressive neoplasm that tends to recur locally and to metastasize. Despite the poor response to standard therapy combining surgical resection, postoperative irradiation and chemotherapy, the results might change due to current research on genetic therapy based on creating antisense oligonucleotides against the EWS-FLI 1 fusion gene.

Adult↗
PubMed2004

Results of a phase II upfront window of pharmacokinetically guided topotecan in high-risk medulloblastoma and supratentorial primitive neuroectodermal tumor.

PURPOSE: To assess the antitumor efficacy of pharmacokinetically guided topotecan dosing in previously untreated patients with medulloblastoma and supratentorial primitive neuroectodermal tumors, and to evaluate plasma and CSF disposition of topotecan in these patients. PATIENTS AND METHODS: After maximal surgical resection, 44 children with previously untreated high-risk medulloblastoma were enrolled, of which 36 were assessable for response. The topotecan window consisted of two cycles, administered initially as a 30-minute infusion daily for 5 days, lasting 6 weeks. Pharmacokinetic studies were conducted on day 1 to attain a topotecan lactone area under the plasma concentration-time curve (AUC) of 120 to 160 ng/mL.h. After 10 patients were enrolled, the infusion was modified to 4 hours, with dosage individualization. RESULTS: Of 36 assessable patients, four patients (11.1%) had a complete response and six (16.6%) showed a partial response, and disease was stable in 17 patients (47.2%). Toxicity was mostly hematologic, with only one patient experiencing treatment delay. The target plasma AUC was achieved in 24 of 32 studies (75%) in the 30-minute infusion group, and in 58 of 93 studies (62%) in the 4-hour infusion group. The desired CSF topotecan exposure was achieved in seven of eight pharmacokinetic studies when the topotecan plasma AUC was within target range. CONCLUSION: Topotecan is an effective agent against pediatric medulloblastoma in patients who have received no therapy other than surgery. Pharmacokinetically guided dosing achieved the target plasma AUC in the majority of patients. This drug warrants testing as part of standard postradiation chemotherapeutic regimens. Furthermore, these results emphasize the importance of translational research in drug development, which in this case identified an effective drug.

Adolescent↗
PubMed2003

Melanotic neuroectodermal tumor of infancy in the soft tissues of the arm: fine needle aspiration biopsy and histologic correlation-a case report.

A case of melanotic neuroectodermal tumor of infancy (MNTI) presenting as a soft tissue mass in the right arm of a 6-mo female child is discussed. The mass was diagnosed by fine-needle aspiration biopsy (FNAB) and confirmed by histological examination. This communication emphasizes the characteristic cytology of MNTI and discusses its significance in the context of this tumor occurring in the soft tissues. The cytology smears were distinctive in showing a dual population of small, rounded, undifferentiated cells and larger melanin-containing epithelial-like cells. It is the identification of the latter cells in the smears which differentiates this tumor from other round cell tumors of infancy and helps in the correct diagnosis by FNAB.

Arm↗
PubMed2002

Atypical pleomorphic extraosseous ewing tumor/peripheral primitive neuroectodermal tumor with unusual phenotypic/genotypic profile.

A pleomorphic undifferentiated tumor primarily located in the retroperitoneum with a phenotype compatible with an extraosseous Ewing tumor/peripheral primitive neuroectodermal tumor (ET/pPNET) pattern and unusual molecular features is described. Immunohistochemically, HBA-71 (CD99/mic2) and several neural markers were intensively expressed together with scattered cells expressing carcinoembryonic antigen (CEA). Short-term culture showed biphasic neuroblastic and epithelioid cell populations, with the latter expressing germ cell markers (CEA, alpha-fetoprotein, and the beta-subunit of chorionic gonadotrophin). Conventional cytogenetics displayed several chromosomic rearrangements, especially a complex translocation t(17,2,22,13) (q21::q11-->q33::q12-->q13::q14). These structural abnormalities were confirmed using fluorescence in situ hybridization analysis. Molecular studies revealed EWS-FEV fusion transcripts (exon 7 of the EWS gene and exon 2 of the FEV gene). In addition, a new p53 mutation not previously reported in ET/pPNET involving exon 5 codon 138: GCC to GAC (Ala/Asp) was detected. In our case, we emphasize the presence of atypical features not only from the phenotypic point of view but also at the genetic level as well as the value of detecting such markers in the differential diagnosis with other abdominal pleomorphic tumors.

Adult↗
PubMed2003

A novel case of a CAT to AAT transversion in codon 179 of the p53 gene in a supratentorial primitive neuroectodermal tumor harbored by a young girl. Case report and review of the literature.

BACKGROUND: The most common cytogenetic abnormality encountered in primitive neuroectodermal tumors (PNET)/medulloblastoma is loss of heterozygosity in the region of the short arm of chromosome 17. There is some evidence that supratentorial PNET has different cytogenetic markers than infratentorial PNET/medulloblastoma. Particularly, loss of 17p is more frequent in the latter than in the former. We describe a young girl diagnosed with supratentorial PNET (SPNET). Analysis of the tumor suppressor gene p53 in the tumorous tissue revealed a rare transversion mutational event of CAT to AAT in position 179 of exon 5. To the best of our knowledge, this is the first case of such a transversion at codon 179 in the p53 gene in SPNET. CASE REPORT: A 12-year-old girl was admitted with nausea, headache and vision disturbances. MRI of the brain showed a large space- occupying lesion in the right frontal lobe. Histological examination of the macroscopic resection of the tumor revealed PNET of the brain. Polymerase chain reaction-single strand conformation polymorphism analysis of all p53 exons was performed, and a unique variant of a transversion at codon 179 of exon 5 was revealed. Therapy was started according to the Children's Cancer group protocol (CCG-99702) designated for treatment of high-risk central nervous system embryonal tumors. She received an initial course of chemotherapy, consisting of cyclophosphamide and vincristine for mobilizing and harvesting peripheral blood stem cells (PBSCs). Then she was given craniospinal irradiation (3,600 cGy) with a boost to the tumor bed (1,980 cGy) and three consecutive courses of high-dose chemotherapy with carboplatin, vincristine and thiotepa/cyclophosphamide, with PBSCs support after each course. RESULTS: The patient is in complete remission 17 months after diagnosis, based on the results of physical examination and imaging studies. DISCUSSION: The mutation results in an alteration of the amino acid HIS to ASN. The amino acids surrounding position 175 play an important role in stabilizing the p53/DNA complex. There are only 12 known mutations of the reported type, and the finding of such a rare mutational event in a low-incidence p53 mutation tumor, such as SPNET, might add additional insight into the p53-SPNET relationship in tumorigenesis. Although not widely accepted, it is possible that different mutations of the p53 gene in patients with brain tumors may imply a different ultimate prognosis. In our case, we cannot exclude the fact that transversion of CAT to AAT in position 179 of exon 5 may explain prolonged survival of a patient with good response to therapy.

Child↗
PubMed1997

Renal primitive neuroectodermal tumor: a morphologic, cytogenetic, and molecular analysis with the establishment of two cultured cell lines.

We report two patients with renal primitive neuroectodermal tumor (PNET) in whom the diagnosis was established by both a cytogenetic and a molecular analysis. Histologically, both renal tumors were composed of uniform immature round cells with a positive immunoreactivity for O13 (p30/32 MIC2). The cytogenetic analysis with in situ hybridization (chromosome painting) demonstrated reciprocal translocation t(11;22)(q24;q12) specific to PNET in the cultured cells derived from each tumor. The reverse transcriptase-polymerase chain reaction (RT-PCR) in both tumors demonstrated EWS/ FLI-1 fusion transcripts, representing the molecular equivalent of t(11;22). A Southern blot analysis also confirmed EWS gene rearrangement in both renal tumors. In addition, the authors also established two new cell lines (designated as FU-RPNT-1 and FU-RPNT-2) from renal PNETs. When transplanted into athymic mice, FU-RPNT-1 and FU-RPNT-2 reproduced and maintained the morphologic and molecular characteristics of the original tumors. In conclusion, the detection of t(11;22) and EWS/FLI-1 fusion transcripts is considered to provide a novel adjunctive method for diagnosing renal PNET. These newly established cell lines thus may be used to investigate the biologic behavior related to renal PNETs.

Adult↗
PubMedDate not supplied

Melanotic neuroectodermal tumor of infancy: clinical, radiological, and pathological features.

We present a case of a 4-month-old female infant with a maxillary melanotic neuroectodermal tumor of infancy (MNTI) and review the pooled data from previous publications on this entity. The literature to date comprises 378 reported cases from 1918 to the present, from which data on the presence or absence of metastatic disease was available in 311, and on the presence or absence of local recurrence in 165. These pooled data suggest a local recurrence rate of 36% with metastasis occurring in 7% of cases. At present, the optimal management includes complete surgical excision with clear margins, but there are no reliable histopathological or molecular features to predict the biological behavior in individual cases.

Antigens, Neoplasm↗
PubMed1995

Human interferon-beta therapy for cerebral primitive neuroectodermal tumors--two case reports.

A 5-year-old girl and a 2-year-old boy presented with recurrent cerebral primitive neuroectodermal tumor (PNET) and were treated with intravenous administration of human fibroblast interferon (HuIFN-beta) which was continued as outpatient maintenance therapy. Both patients showed a partial response and were still alive 14 months and 2 years after diagnosis. Our results suggest that HuIFN-beta is an effective therapy for PNET, and can be used as long-term maintenance therapy without serious side effects.

Brain↗