1/4. Rosetted glioneuronal tumor: a case with proliferating neuronal nodules.Glioneuronal tumors with neuropil-like islands (rosetted glioneuronal tumors) were recently reported as a novel brain tumor entity with characteristic clinicopathological features (Am J Surg Pathol 23: 502, 1999). Here we describe the clinical, histological and genetic features of another case arising in the parietal lobe of a 43-year-old man suffering from focal motor epilepsy. Histologically, nodules of small neuronal tumor cells immunoreactive for synaptophysin and NeuN were embedded within a diffuse astrocytoma. Remarkably, highest proliferative activity was observed within the neuronal nodules. comparative genomic hybridization revealed a gain of chromosome 7q and a loss on chromosome 9p.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/4. genome-wide survey for chromosomal imbalances in ganglioglioma using comparative genomic hybridization.ganglioglioma is a mixed neuronal and glial tumor first described by Perkin in 1926. Because of its rare occurrence in the central nervous system, the pathogenesis of this neoplasm is still largely unknown. Previous studies of ganglioglioma mainly focused on histologic features, immunohistochemical analysis, clinical treatment, and patient outcome. Very few cytogenetic and molecular genetic studies have been reported on this neoplasm. To better understand the mechanism underlying the development of ganglioglioma, we performed comparative genomic hybridization analysis to investigate chromosomal imbalances across the entire genome in five cases of gangliogliomas. Loss of genetic material on the short arm of chromosome 9 was a common genetic alteration found in three of five cases. Overrepresentation of partial or the whole chromosome 7 was another recurrent chromosomal imbalance, confirmed by fluorescence in situ hybridization. Immunohistochemical analysis was performed; all five cases revealed no reaction or low expression for epidermal growth factor receptor antibody. Our study highlights chromosomal regions for further fine mapping and investigation of candidate tumor suppressor genes involved in the pathogenesis of ganglioglioma.- - - - - - - - - - ranking = 6keywords = hybridization (Clic here for more details about this article) |
3/4. Desmoplastic infantile astrocytoma and ganglioglioma: a search for genomic characteristics.In the present study the clinical data, histology, proliferation rate, dna ploidy status and the results of TP53 mutation analysis and comparative genomic hybridization (CGH) of three typical cases of desmoplastic infantile astrocytoma and ganglioglioma are presented. Postoperative disease-free intervals of 11, 8 and 3 years were recorded and in none of the cases were radiological signs of tumor recurrence. No TP53 mutations (exons 5-8) were found. CGH analysis revealed loss of 8p22-pter in one case, while in another case gain of 13q21 was detected. In the case with the follow-up of 11 years an aneuploid dna-flow cytogram along with slightly increased MIB-1 labeling index (LI) was found. The results demonstrate little genetic instability in these low-grade lesions. dna-aneuploidy seems not to be indicative of tumor progression. It is concluded that the genetic aberrations found in desmoplastic infantile ganglioglioma differ from those encountered in common astrocytomas.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/4. Malignant rhabdoid meningioma arising in the setting of preexisting ganglioglioma: a diagnosis supported by fluorescence in situ hybridization. Case report.A highly malignant brain neoplasm with rhabdoid morphological features emerged in the bed of a subtotally resected ganglioglioma in a 54-year-old retired nuclear submarine officer. A combined application of neuroimaging, immunohistochemical studies, electron microscopy, and fluorescence in situ hybridization (FISH) was used to establish the morphological identity of the tumor. The rhabdoid appearance of the tumor cells indicated either an especially malignant variant of rhabdoid meningioma or an atypical teratoid/rhabdoid tumor with an unusually late onset. Whereas immunohistochemical studies and electron microscopy could only be used to narrow down the differential diagnosis, FISH revealed loss of one copy of NF2 with preservation of the INI1 region on 22q, thus establishing the identity of the tumor.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |