title: Glioblastomatous transformation of ganglioglioma: case report with reference to molecular genetic and flow cytometric analysis.
abstract: Gangliogliomas generally behave as benign indolent tumors. However, gangliogliomas undergoing malignant transformation have also been reported. The molecular basis for the malignant transformation of gangliogliomas remains unclear. We describe a case of ganglioglioma, which had transformed to glioblastoma after the gross total resection of the original tumor, in a 4-year-old girl. The present case is unusual in four aspects: (i) it arose from a low-grade ganglioglioma in the absence of previous radiation or chemotherapy, which is the fourth reported case; (ii) the original tumor showed a high proliferative index on flow cytometry but a low Ki-67 labeling index, implying that the application of flow cytometry might play a certain role in predicting biological and clinical behavior of low grade gangliogliomas; (iii) p53 mutation and deletion appeared in the secondary glioblastoma, which was not shown in the original well-differentiated ganglioglioma; and (iv) the transformed glioblastoma showed p16 inactivation detected by methylation and deletion, which are relatively uncommon genetic events in secondary glioblastomas. This is the first report of a genetic alteration in glioblastoma arising from a well differentiated ganglioglioma prior to radiation or chemotherapy. Based on the above findings, irrespective of radiotherapy or chemotherapy, rare recurrence of malignant evolution, especially tumors of high S-phase fraction on flow cytometry, warrants long-term follow-up, even in a well-differentiated ganglioglioma.
authors: Department of Pathology, Gachon Medical School Gil Medical Center, Incheon, Korea.
authors: Na Rae
authors: NR
authors: Kim
authors: Kyu-Chang
authors: KC
authors: Wang
authors: Jae-Seung
authors: JS
authors: Bang
authors: Gheeyoung
authors: G
authors: Choe
authors: Young
authors: Y
authors: Park
authors: Seung-Ki
authors: SK
authors: Kim
authors: Byung-Kyu
authors: BK
authors: Cho
authors: Je G
authors: JG
authors: Chi
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D002471:Cell Transformation, Neoplastic; D002675:Child, Preschool; D003131:Combined Modality Therapy; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D005434:Flow Cytometry; D018303:Ganglioglioma / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D005909:Glioblastoma / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D006801:Humans; D008279:Magnetic Resonance Imaging; D008967:Molecular Biology; D009154:Mutation; D009364:Neoplasm Recurrence, Local; D016609:Neoplasms, Second Primary / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D011123:Polyploidy; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm