Cerebral Primitive Neuroectodermal Tumor Research Articles

Tandem high-dose chemotherapy with stem cell rescue followed by risk-adapted radiation in children with high-risk cerebral primitive neuroectodermal tumor: Results of the prospective SFCE-trial PNET HR+5.

10007 Background: To assess the 3-year progression-free survival (PFS) rate of patients with newly diagnosed high-risk medulloblastoma (MB) or supratentorial primitive neuroectodermal tumor (sPNET)...

Tumor disease and associated congenital abnormalities on prenatal MRI

Fetal tumors can have a devastating effect on the fetus, and may occur in association with congenital malformations. In view of the increasing role of fetal magnetic resonance imaging (MRI) as an adjunct to prenatal ultrasonography (US), we sought to demonstrate the visualization of fetal tumors, with regard to congenital abnormalities, on MRI. This retrospective study included 18 fetuses with tumors depicted on fetal MRI after suspicious US findings. An MRI standard protocol was used to diagnose tumors judged as benign or malignant. All organ systems were assessed for tumor-related complications and other congenital malformations. Available US results and histopathology were compared with MRI. There were 13/18 (72.2%) benign and 5/18 (27.8%) malignant tumors diagnosed: a cerebral primitive neuroectodermal tumor in 1/18, head-neck teratomas in 4/18; ventricular rhabdomyomas in 4/18; a cardiac teratoma in 1/18; a hepatoblastoma in 1/18; neuroblastomas in 2/18; a cystic hemorrhagic adrenal hyperplasia in 1/18; a pelvic leiomyoma in 1/18; sacrococcygeal teratomas in 3/18. Tumor-related complications were present in 13/18 (72.2%) cases; other congenital abnormalities in 3/18 (16.7%). MRI diagnosis and histology were concordant in 8/11 (72.7%) cases. In 6/12 (50%) cases, US and MRI diagnoses were concordant, and, in 6/12 (50%) cases, additional MRI findings changed the US diagnosis. Our MRI results demonstrate the visualization of fetal tumors, with frequently encountered tumor-related complications, and other exceptional congenital abnormalities, which may provide important information for perinatal management. Compared to prenatal US, MRI may add important findings in certain cases.

Neurological complications without eclampsia during pregnancy in Turkey

Some neurological diseases associated with pregnancy may develop initially during gestation, pregnancy may predispose the patient to some of these diseases or some may occur only with pregnancy. The aim of this study is to draw attention to the rare neurological diseases--other than eclampsia--that develop during pregnancy or the diseases initially described as associated with pregnancy. Our sample comprised of 16 pregnant women who developed neurological disorders that are rarely encountered or initially reported during this phase, eclampsia excluded. The proportion of cerebrovascular diseases was 56%. The others included intracranial hypotension accompanied by seizures, cerebral primitive neuroectodermal tumor, ophthalmoplegic migraine, hemiplegic migraine, spinal segmental myoclonus, acute motor axonal neuropathy and acute motor axonal neuropathy associated with ophthalmoplegia. Our results suggest that by adopting a careful and correct approach and accurate neurological diagnosis, most of these patients could be treated successfully with good prognosis of the newborns.

Cerebral primitive neuroectodermal tumor in an adult with a heterozygous MSH2 mutation

A 37-year-old woman presented with a supratentorial cerebral mass, which was diagnosed histologically as a primitive neuroectodermal tumor. She had been treated for rectal adenocarcinoma 7 years previously. A family history revealed a young-onset colorectal carcinoma in the patient's father. Immunohistochemical analysis for DNA mismatch repair proteins, germline mutation analysis of MSH2. Lynch syndrome with a heterozygous germline mutation in MSH2. Debulking of the cerebral tumor, craniospinal axis radiotherapy, and genetic counseling of family.

Autologous hematopoietic stem cell transplantation for high-risk brain tumors in children

Autologous hematopoietic stem cell transplant (AHSCT) has been advocated as a form of salvage therapy for children with high-risk or relapsed brain tumors but only limited data are available currently. We report the outcomes of pediatric brain tumors treated with AHSCT in a quaternary referral center in Hong Kong over 10 years (June 1996–May 2006). Thirteen patients with medulloblastoma (n = 9), cerebral primitive neuroectodermal tumor (n = 1), ependymoma (n = 1), germ cell tumor (n = 1) and cerebellar rhabdoid (n = 1) were transplanted because of tumor residual (n = 1) or recurrence (n = 12). Uniform upfront treatment protocols were adopted according to specific tumor types. Prior to AHSCT, 8 patients (61.5%) achieved complete remission and 5 (38.5%) were in partial remission. Conditioning employed thiotepa 300 mg/m2, etoposide 250 mg/m2 and carboplatin 500 mg/m2 daily for 3 days. Toxicity included mucositis and neutropenic fever in all patients, grade 4 hepatic toxicity in 4 patients (including hepatic veno-occlusive disease in 2 patients) and grade 4 renal toxicity in 1 patient. The 5-year event-free survival was 53.9%. Five patients died of disease recurrence or progression 8–21 months after transplant with a median disease-free period of 8 months post-transplant. One died of transplant-related complications in the early post-transplant period. Seven survived for a median of 5.4 years (maximum follow-up of 9.8 years), with six having Lansky-Karnofsky performance score above 80. All survivors had complete remission before transplant though 2 had leptomeningeal spread. We conclude that AHSCT can achieve long-term survival in children with recurrent brain tumor. However, those with macroscopic residual tumor before transplant cannot be salvaged.

Neonatal Macrocephaly: Cerebral Primitive Neuroectodermal Tumor or Neuroblastoma as an Infrequent Cause-A Case Report and Review of the Literature

We report a male term newborn presenting with a congenital macrocephaly 3.5 standard deviations above the median, with a wide and tense anterior fontanel, splayed calvarial sutures, and muscular hypotonia. Antenatal head circumferences were repeatedly below the median. A postnatal head ultrasound showed a large right intracerebral mass with right lateral ventricle compression, right temporal horn dilation, and right frontal horn enlargement with lateral displacement. Additional imaging by computed tomography scan and magnetic resonance imaging was performed. A decompression was performed and histology, immunohistochemistry, and molecular biology supported the diagnosis of a primitive neuroectodermal tumor. A MYCN gene amplification assay remained negative. The incidence of neonatal brain tumors is between 1.4 and 4.1/100,000 live births. Their most common presentation is macrocephaly, hydrocephalus, stillbirth, or diagnosis by pre- or postnatal imaging. Although hydrocephaly and intra- or extracranial hemorrhage are the most frequent causes of congenital macrocephaly, this should be initially investigated by head ultrasound. A suspected malignancy will be confirmed by histopathology, immunohistochemistry, and molecular biology.

Neonatal macrocephaly: cerebral PNET (Primitive Neuro Ectodermal Tumor) or neuroblastoma as an infrequent cause: a case report and a review of the literature

Case presentation: We report a male term newborn with a congenital macrocephaly, 3.5 standard deviation above median noted at birth. The antenatal history, including ultrasonography was reported to be normal. The head circumference was measured between 10th and 50th percentile at 21 weeks 3/ 7 and 30 weeks 5/ 7, respectively. Postnatal adaptation was complicated by poor respiratory effort and the baby had to be intubated at 8 minutes of age.

Neonatal macrocephaly: cerebral PNET (Primitive Neuro Ectodermal Tumor) or neuroblastoma as an infrequent cause: a case report and a review of the literature

Neonatal macrocephaly: cerebral PNET (Primitive Neuro Ectodermal Tumor) or neuroblastoma as an infrequent cause: a case report and a review of the literature

Neonatal macrocephaly: cerebral PNET (Primitive Neuro Ectodermal Tumor) or neuroblastoma as an infrequent cause: a case report and a review of the literature

Neonatal macrocephaly: cerebral PNET (Primitive Neuro Ectodermal Tumor) or neuroblastoma as an infrequent cause: a case report and a review of the literature

Temozolomide in resistant or relapsed pediatric solid tumors

We report the off-label study aimed at investigating the use of temozolomide (TMZ) as single agent in relapsed or resistant pediatric solid tumors. The drug was administered at the dose of 215 mg/m2/day x 5 days or 180 mg/m2/day x 5 days in patients with prior craniospinal irradiation (CSI) or autologous bone marrow transplantation (ABMT). Fifty two patients, median age 127.6 months, with resistant or relapsed solid tumors were enrolled. Tumor types were: neuroblastoma (NB; n = 17), medulloblastoma (MB; 8), brain stem glioma (BSG; 8), extraosseous Ewing's sarcoma/peripheral neuroectodermal tumor (EOES; 4), Ewing's sarcoma (ES; 4), anaplastic astrocytoma (AA; 3), rhabdomyosarcoma (RMS; 2), ependymoma (EP; 2), cerebral primitive neuroectodermal tumor (cPNET; 2), hepatocarcinoma (HC; 1), and osteosarcoma (OS; 1). All patients were pre-treated. Two outpatient courses were administered, with a median of 4.8 courses/pt. Objective response-rate (CR + PR + MR) in our series was 13.4% (1.9% CR, 3.8% PR, and 7.7% MR), SD occurred in 38.4% of patients and 48% had PD. The median survival was 7.8 months (range 1-37) and median time to progression was 3.4 months (range 1-20); these data were significantly correlated with histology and previous nitrosureas administration in multivariate analysis. Haematological toxicity grade 3-4 (mainly thrombocytopenia) was observed in 21.4% of administered courses, nausea was reported in 3.1% and respiratory distress in 0.7%. Oral TMZ was well tolerated in children with resistant or relapsed solid tumors and showed activity in NB and CNS tumours refractory to standard chemotherapy.

High-dose chemotherapy with autologous hematopoietic stem-cell rescue for patients with malignant brain tumors.

This article reviews recent reports on high-dose chemotherapy combined with autologous stem-cell rescue for patients with newly diagnosed or recurrent malignant brain tumors. Children with newly diagnosed malignant central nervous system (CNS) tumors are included - in these patients it was desirable to avoid radiotherapy. The drugs used were thiotepa, etoposide, cyclophosphamide, busulfan, melphalan, and carboplatin. At a toxic death rate of 8-13%, their toxicity was considered acceptable. However, in patients receiving high-dose chemotherapy, neurologic complications were not uncommon. Therefore, the effects of this drug therapy on the post-treatment cognitive function of long-term survivors must be examined prospectively. Regarding the types of tumor that respond to drug therapy, medulloblastoma and cerebral primitive neuroectodermal tumor (PNET) appear to be good candidates, as are malignant astrocytic tumors in the cerebral hemisphere of children younger than 3 years. On the other hand, brain stem gliomas do not appear to respond well to high-dose chemotherapy. Radiotherapy can be avoided in a significant proportion of young children with malignant brain tumors. Larger patient series need to be studied to determine which patients are most likely to benefit from high-dose chemotherapy and to pinpoint the optimal time for treatment intervention.

Gangliosides and neutral glycolipids in ependymal, neuronal and primitive neuroectodermal tumors.

Neutral glycolipid and ganglioside compositions were determined on 11 ependymal tumors, 12 medulloblastomas, 6 other neuronal tumors of the brain, 4 peripheral neuroblastomas, 1 cerebral primitive neuroectodermal tumor (PNET), and 1 PNET of the thoracic wall. Within the group of tumors that can demonstrate neuronal phenotypes, there was an association between the degree of neuronal differentiation usually demonstrated by these tumors and the proportions of both GD1a and 1b-pathway gangliosides. The amount of globoside also correlated with the amount of 1b pathway gangliosides. Patients with medulloblastomas whose 1b gangliosides made up over 15% of the total gangliosides survived longer that those with lower proportions of 1b gangliosides. The only gangliosides in the choroid plexus papilloma were GM3 and GD1a, but other ependymal tumors had significant amounts of GD1b and its metabolic precursors. Ependymoma and anaplastic ependymoma had similar neutral glycolipid compositions, which were different from subependymoma, which lacked ceramide monohexoside and ceramide dihexoside. These differences in glycolipid compositions suggest that there may be fundamental biological differences between these types of ependymal tumors.

Alternative RNA splicing of the hyaluronic acid receptor CD44 in the normal human brain and in brain tumors.

The cell-surface receptor for hyaluronic acid, CD44, is expressed by both normal and malignant cells. Numerous CD44 isoforms have recently been identified that are derived by alternative ribonucleic acid splicing. The expression of some CD44 isoforms has been shown to be involved in tumor progression and metastatic spread in a rat carcinoma model and in human carcinomas. In the present study, CD44 isoform expression was evaluated by reverse transcriptase-polymerase chain reaction (PCR) analysis in frozen sections derived from three samples of normal brain tissue and from 40 brain tumors, including samples of glioblastoma multiforme, anaplastic astrocytoma, low-grade astrocytoma, cerebral primitive neuroectodermal tumor, medulloblastoma, metastatic colon carcinoma, and metastatic melanoma. Normal brain tissue adjacent to the tumors was also examined in 14 of 18 glioblastomas. In all normal brain and tumor samples, with the exception of metastases from colon carcinoma, PCR analysis demonstrated one prominent product that corresponded to the CD44H hematopoietic form of CD44. Metastases from colon carcinoma demonstrated two prominent PCR amplification products corresponding to CD44H and CD44R1. These results suggest that CD44H is the predominant isoform of this protein in normal human brain tissue and in human neuroectodermal tumors of varying degrees of malignancy. The ability of CD44H to mediate tumor cell motility and invasiveness (in contrast to CD44R1) suggests that the CD44 alternative splicing pattern of neuroectoderm-derived tumors may enhance their local biological aggressiveness and intracerebral spread. The lack of expression of larger molecular weight CD44 variants by primary brain tumors may also partially explain why these tumors rarely metastasize to distant sites.

Neuraxis dissemination in pediatric brain tumors. Response to preirradiation chemotherapy

Of 29 consecutive children treated for malignant primary tumors of the central nervous system (CNS) at this institution, postoperative examination showed radiographic or cytologic evidence of neuraxis dissemination in 10 (34%). Given the historically poor results in disseminated CNS tumors treated with surgery and radiation therapy alone, these ten patients were treated prospectively with an investigational Phase II protocol consisting of preirradiation cisplatin (90 mg/m2 on day 1) and etoposide (150 mg/m2 on days 3 and 4). The diagnoses included medulloblastoma (n = 4), malignant glioma (n = 3), cerebral primitive neuroectodermal tumor (n = 1), pineoblastoma (n = 1), and mixed glioma of the brainstem (n = 1). Postoperative neuraxis scanning with computed tomography, magnetic resonance imaging, or spinal myelography showed measurable intracranial or spinal metastases in all children. The cerebrospinal fluid (CSF) cytologic examination was positive for tumor cells in five. The best responses, based on serial imaging of neuraxis metastases, included two complete responses, four partial responses, and three stable disease states. One patient had progressive disease at the primary site despite stable disease in the spine; progressive neuraxis disease was documented in only one patient during chemotherapy. Clearance of tumor cells from the CSF was documented in three patients. The adverse effects of chemotherapy, consisting of transient myelosuppression and mild ototoxicity, were minimal. Reversible neurologic deterioration occurred in two patients; one patient became acutely quadriplegic after a prolonged convulsive seizure without radiographic evidence of tumor progression.

Cerebral primitive neuroectodermal tumor in an adult, with spinal cord metastasis after 18-year dormancy

A cerebral primitive neuroectodermal tumor in a 40-year-old man recurred as a metastasis to the spinal cord after an 18-year dormant period. The metastatic tumor showed features of neuronal differentiation. The clinical course and pathologic findings are discussed.

Congenital cerebral primitive neuroectodermal tumor with astrocytic differentiation and extracranial metastases

A cerebral primitive neuroectodermal tumor with astrocytic differentiation and extracranial metastases in a 28-day-old infant is reported. The infant presented with a progressively enlarged head, cutaneous lesions in the neck, and enlarged cervical lymph nodes. A computed tomography brain scan demonstrated a giant thalamic tumor with subarachnoid dissemination and hydrocephalus. Biopsy material from the cervical lesions showed a picture of glioma with anaplastic astrocytes. The patient received a ventriculoperitoneal shunt operation and palliative chemotherapy, but died at 3 months of age. Autopsy was performed. Histological studies, which included immunohistochemical stains of the thalamic tumor, showed small, round, primitive, neoplastic cells with focal astrocytic differentiation.

Membranous alterations in the cytoplasm and nucleus in a primitive neuroectodermal tumor of the brain

The ultrastructure of a cerebral primitive neuroectodermal tumor has been reported previously. In the present case, we will present some unusual previously unreported membranous structures and alterations in the cytoplasm and nucleus of the tumor cells.Specimens were cut into small pieces about 1 mm3 and immediately fixed in 4% glutaraldehyde in phosphate buffer for two hours, then post-fixed in 1% buffered osmium tetroxide for one hour. After dehydration, tissues were embedded in Epon 812. Thin sections were stained with uranyl acetate and lead citrate.In the cytoplasm of the tumor cells, we found paired cisternae (Fig. 1) and annulate lamellae (Fig. 2) noting that the annulate lamellae were sometimes associated with the outer nuclear envelope (Fig. 3). These membranous structures have been reported in other tumor cells. In our case, mitochondrial to nuclear envelope fusions were often noted (Fig. 4). Although this phenomenon was reported in an oncocytoma, their frequency in the present study is quite striking.