Gliosarcoma WHO Grade IV-Giant Cell Glioblastoma WHO Grade IV

Abstract

Gliosarcoma (WHO grade IV) is a variant of IDH-wild-type glioblastoma, characterized by a biphasic tissue pattern with alternating areas displaying glial and mesenchymal differentiation.It is an infiltrating, well-demarcated mass, often with cystic components, and heterogeneous enhancement. It can often not be distinguished from glioblastoma multiforme.Histologically, gliosarcoma shows a biphasic tissue pattern composed of a mixture of gliomatous and sarcomatous tissues. The gliomatous component consists of anaplastic astrocytic tumor cells like in glioblastoma, while the sarcomatous component shows signs of malignant transformation of cells with epithelial differentiation and mesenchymal differentiation.Pathogenetically, the sarcomatous component results from advanced glioma dedifferentiation with expression of TP53 in both tumor components, identical PTEN and TP53 mutations in both components, P16 deletion in both components, and MDM2 and CDK4 co-amplification in both components.Treatment consists of surgery, radiotherapy, and chemotherapy. Gliosarcoma has a poor prognosis which is somewhat more favorable than glioblastoma.Giant cell glioblastoma (WHO grade IV) is a rare histological variant of IDH-wild-type glioblastoma, histologically characterized by bizarre, multinucleated giant cells and an occasionally abundant reticulum network. Radiologically it is indistinguishable from glioblastoma multiforme.Histologically, the tumor is characterized by numerous multinucleated giant cells with bizarre appearance and a large number of nuclei (to more than 20).The tumor occurs de novo after short preoperative history without clinical or radiologic evidence of a less malignant precursor lesion.Treatment includes surgery, radiotherapy, and chemotherapy. Giant cell GBM has a poor prognosis and shows lesser infiltrative behavior than glioblastoma.