Primitive Neuroepithelial Tumor Research Articles

Ewing Sarcoma of Orbit with Intracranial Extension

Ewing sarcoma causing unilateral proptosis in a child is unusual presentation. Ayoung girl presented with painless proptosis of left eye with restricted eyemovements. Her radiology revealed a large soft tissue mass causing destructionof lateral orbital wall and zygomatic arch measuring 2.0 × 3.0 cm. Total excisionof intracranial and intra orbital part of the tumor brought about substantial relief.The clinical and radiological presentation and management of this entity arediscussed.Key words: Sphenoid bone, Ewing sarcoma, orbital proptosis, primitiveneuroepithelial tumor (PNET), radiology, small round cell tumor, surgery.

ASPP2 Binds Par-3 and Controls the Polarity and Proliferation of Neural Progenitors during CNS Development

Cell polarity plays a key role in the development of the central nervous system (CNS). Interestingly, disruption of cell polarity is seen in many cancers. ASPP2 is a haplo-insufficient tumor suppressor and an activator of the p53 family. In this study, we show that ASPP2 controls the polarity and proliferation of neural progenitors in vivo, leading to the formation of neuroblastic rosettes that resemble primitive neuroepithelial tumors. Consistent with its role in cell polarity, ASPP2 influences interkinetic nuclear migration and lamination during CNS development. Mechanistically, ASPP2 maintains the integrity of tight/adherens junctions. ASPP2 binds Par-3 and controls its apical/junctional localization without affecting its expression or Par-3/aPKC lambda binding. The junctional localization of ASPP2 and Par-3 is interdependent, suggesting that they are prime targets for each other. These results identify ASPP2 as a regulator of Par-3, which plays a key role in controlling cell proliferation, polarity, and tissue organization during CNS development.

Phase II evaluation of intravenous vinorelbine (Navelbine) in recurrent or refractory pediatric malignancies: A Children's Oncology Group study

A Phase II trial was developed to determine the efficacy and toxicity of intravenous vinorelbine, a semi-synthetic vinca alkaloid, in children, adolescent, and young adults with recurrent or refractory solid malignancies. Fifty patients were enrolled among three strata: soft tissue sarcomas [rhabdomyosarcoma (RMS), non-rhabdomyosarcoma, primitive neuroepithelial tumor] (20 patients); brain tumors [astrocytoma (4 patients), medulloblastoma (2 patients), other (16 patients)] (22 patients); neuroblastoma (8 patients). Vinorelbine was given weekly for 6 consecutive weeks during an 8-week interval. The response rate and toxicity profile was assessed. Among the first 35 patients treated at 33.75 mg/m(2)/dose, 25 experienced grades 3-4 neutropenia (75%). The dose was decreased to 30 mg/m(2)/dose in the remaining 15 patients. The median age was 10 years (range, 1-25). Four responses (one complete, three partial) occurred within the soft tissue sarcoma strata (all with RMS) and two occurred in the brain tumor group (medulloblastoma and astrocytoma). The most common toxicities were hematological and neurological. Vinorelbine at dose of 30 mg/m(2) can be safely administered to children with recurrent or refractory solid malignancies. The study design identified vinorelbine to be active in the sarcoma category, with a response rate of 36% (4/11) among RMS patients.

Extraneural metastases of anaplastic oligodendroglial tumors

Extraneural metastases of malignant gliomas are rare. According to the literature, they tend to appear in glioblastoma patients, but are exceptionally rare in anaplastic oligodendroglioma. We report on an anaplastic oligodendroglioma and an anaplastic oligoastrocytoma that metastasized to cervical lymph nodes and bones. Both patients were women aged 54 and 30 years, and the metastases appeared following craniotomy. In the first patient, metastases to cervical lymph nodes developed one year after surgery, and, despite adjuvant therapy, recurred in the same location several times. Fine needle aspiration biopsy (FNAB) of the cervical lymph node prior to neck dissection suggested a possible metastatic primitive neuroepithelial tumor. In the second case, metastases to the sacrum and femur developed after surgery for a recurrent anaplastic oligoastrocytoma. Our two cases reconfirm a rare but definite ability not only of glioblastoma but also of anaplastic oligodendroglioma, namely to metastasize to extraneural sites. It is important to bear this in mind, particularly in cases when the history of primary brain tumor is unavailable. In such instances, the correct diagnosis of the metastatic lesion may be extremely difficult if not impossible.

Neuroectodermal ovarian tumors: a brief overview.

Primary neuroectodermal tumors of the ovary are rare monophasic teratomas composed exclusively or almost exclusively of neuroectodemal tissue. Approximately 60 neuroectodermal tumors of the ovary have been reported in the literature. These tumors were classified as ependymoma, astrocytoma, glioblastoma multiforme, ependymoblastoma or as primitive neuroepithelial tumors such as medullo-blastoma, medulloepithelioma and neuroblastoma. Most tumors were diagnosed in the third and fourth decades of life, but occasionally they were first discovered in children, adolescents or older women. Microscopically, they are identical to equivalent neuroectodermal tumors of the central nervous system. The review of the literature shows that most patients with clinical stage I and II were treated surgically, whereas those with stage III or IV tumors received additional radiation or chemotherapy, or both. The clinical stage at the time of diagnosis is the most important prognostic parameter of these tumors.

A 3 1/2-year-old child with a posterior fossa mass. Pigmented medullomyoblastoma.

A 3½-year-old child was operated on for a midline posterior fossa tumor causing hydrocephalus. On microscopic examination, this tumor demonstrated islands of anaplastic small blue cells separated by spindled fasciculated areas. The latter cells demonstrated cross striations and desmin immunoreactivity. Pigmented areas were also observed. Based on these findings, a final diagnosis of pigmented medullomyoblastoma was determined. Pigmented medullomyoblastoma is a rare tumor. The differential diagnoses to be considered are pediatric tumors that demonstrate rhabdoid differentiation. These include atypical rhabdoid/teratoid tumors, pineoblastomas, and other primitive neuroepithelial tumors.

A 3½-Year-Old Child With a Posterior Fossa Mass

A 3½-year-old child was operated on for a midline posterior fossa tumor causing hydrocephalus. On microscopic examination, this tumor demonstrated islands of anaplastic small blue cells separated by spindled fasciculated areas. The latter cells demonstrated cross striations and desmin immunoreactivity. Pigmented areas were also observed. Based on these findings, a final diagnosis of pigmented medullomyoblastoma was determined. Pigmented medullomyoblastoma is a rare tumor. The differential diagnoses to be considered are pediatric tumors that demonstrate rhabdoid differentiation. These include atypical rhabdoid/teratoid tumors, pineoblastomas, and other primitive neuroepithelial tumors.

DER(16)T(1-16) IS A NONRANDOM SECONDARY CHROMOSOME ABERRATION IN MANY TYPES OF HUMAN NEOPLASIA, INCLUDING MYXOID LIPOSARCOMA, RHABDOMYOSARCOMA AND PHILADELPHIA-CHROMOSOME-POSITIVE ACUTE LYMPHOBLASTIC-LEUKEMIA

An unbalanced translocation between chromosomes 1 and 16, der(16)t(1;16), resulting in trisomy 1q and loss of genetic material from 16q, has been thus far suggested to constitute a nonrandom secondary abnormality in two types of closely related solid tumors - Ewing sarcoma and peripheral primitive neuroepithelial tumor (PNET). We report on three cases of soft tissue tumors, a myxoid liposarcoma, a PNET and a rhabdomyosarcoma, and four cases of hematologic disorders, two acute lymphoblastic leukemias (ALL), an acute mixed leukemia and a refractory anemia, that in addition to primary chromosome abnormalities displayed the presence of the der(16)t(1;16). All three cases of acute leukemia were Philadelphia (Ph) chromosome-positive and all displayed both lymphoid and myeloid antigens. Our results and review of the literature indicate that the occurrence of der(16)t(1;16) is not limited to Ewing sarcoma and PNET, but that acquisition of this abnormality may represent a more general pathway of clonal evolution in several different tumor types including Ph chromosome-positive ALL, myxoid liposarcoma, rhabdomyosarcoma, breast cancer, endometrial adenocarcinoma, myelodysplastic syndromes, acute myeloid leukemia, retinoblastoma, and Wilms' tumor.

Mixed desmoplastic primitive neuroepithelial tumor of infancy: a light microscopic, immunocytochemical, ultrastructural and genetic study

We describe a case of a desmoplastic brain tumor which was initially resected from the right fronto-temporal region in a 2 year-old boy. This nodular, calcified tumor was vascularized by the internal carotid artery and the middle meningeal artery branches. Grossly, it contained several mucoid cysts. Light microscopy showed cords or nests of small cuboidal cells surrounded by a loose connective tissue and desmoplastic areas containing fibers and spindle cells. The cuboidal cells expressed epithelial, neuronal and neuroendocrine markers. Some foci of spindle cells showed glial differentiation. The tumor recurred 16 months later and displayed some characteristics of the small cell neuroepithelial component, mitoses being conspicuous. Electron microscopy revealed undifferentiated clear cells, some containing neurosecretory granules. Karyotyping demonstrated the following formula: < 15 > 46, t(8;11) (q13; q11). The chromosome 11 breakpoint was different from that described in Ewing's sarcoma. This isolated translocation has not been previously reported to our knowledge. These unusual features lead us to report this case and to discuss its pathogenesis.

Mixed desmoplastic primitive neuroepithelial tumor of infancy: a light microscopic, immunocytochemical, ultrastructural and genetic study

Mixed desmoplastic primitive neuroepithelial tumor of infancy: a light microscopic, immunocytochemical, ultrastructural and genetic study

Pathologic Analysis of Primary Brain Tumors

Diffuse astrocytomas of the cerebrum, cerebellum, brain stem, and spinal cord are classified into three groups according to the degree of tumor anaplasia. These groups are the astrocytoma, anaplastic astrocytoma, and glioblastoma multiforme. Juvenile pilocytic astrocytomas have a better prognosis and are clinically and biologically distinct from the diffuse, fibrillary astrocytomas. The prognosis of astrocytomas depends not only on histologic characteristics, but also age of the patient, location of the tumor, and extent of surgical resection. The pattern of invasion into surrounding brain distinguishes gliomas from metastatic carcinomas and sarcomas. Topographic correlations have shown that malignant gliomas may invade the brain for distances of up to several centimeters from the enhancing rim seen on CT scan. However, the junction between glioblastoma and adjacent brain may also be fairly abrupt, with a peripheral margin of less than 1 mm. Recurrent glioblastomas are more widely invasive and often extend into areas that appear normal on CT scan. The optimal site for tumor biopsy corresponds to areas of contrast enhancement. Primitive neuroepithelial tumors are malignant neoplasms with a poor prognosis. They tend to recur locally and metastasize throughout the neuraxis via the CSF. It remains controversial whether these tumors should be classified as a single entity with the potential for differentiation along different cell lines, or whether the categories of neuroblastoma, spongioblastoma, ependymoblastoma, pineoblastoma, and medulloblastoma should be retained as specific entities. The medulloblastoma is the most common of these neoplasms, its clinicopathologic features are well characterized, and the current 5-year survivals of 50 to 60 per cent are better than for other "primitive" neoplasms. Glial fibrillary acidic protein is a specific marker for immature, reactive, and neoplastic astrocytes and ependymal cells. Although the absence of GFAP in a neoplasm does not exclude an astrocytic origin, the presence of GFAP indicates astrocytic or ependymal differentiation. This has important diagnostic applications. The expression of GFAP is used to distinguish astrocytic neoplasms from epithelial or mesenchymal tumors that may on occasion mimic a glioma. The detection of GFAP is also useful in the investigation of tumor histogenesis and differentiation both in vivo and in vitro. Although meningiomas exhibit a wide variety of histologic patterns, most tumors exhibit similar biologic and clinical behavior regardless of the histologic subtype.(ABSTRACT TRUNCATED AT 400 WORDS)

Fetal Cerebellar Tissue Associated with a Primitive Neuro-epithelial Tumor in an Ovarian Teratoma

This is a single case report of an ovarian teratoma. It is a unique case of a primitive neuroepithelial tumor with many similarities to a medullo-blastoma arising in a ovarian teratoma, and the second report of fetal cerebellum occurring in a teratoma of the ovary.