Most common site of glioblastoma multiforme is -
Astrocytomas (including Glioblastoma Multiforme) are the most common type of gliomas. They occur predominantly in the cerebral hemispheres, and occasionally in the spinal cord. Pathologically, astrocytomas have been conventionally divided into 3 progressive histologic grades: fibrillary (most common), gemistocytic and protoplasmic. However, currently WHO classification of astrocytomas is widely used which divides them into 4 grades from grade I (low grade) to grade IV (glioblastoma multiforme) as under. WHO GRADE I ASTROCYTOMA. Also called as diffuse astrocytoma, it is a low-grade tumour having a good prognosis WHO GRADE II (WELL-DIFFERENTIATED) ASTROCYTOMA. It is also called as fibrillary astrocytoma. The tumour distos the underlying brain tissue and merges with the surrounding tissue. Based on the type of astrocytes, three subtypes are distinguished: 1.fibrillary,2.protoplastic and 3.gemistocytic astrocytoma. WHO GRADE III (ANAPLASTIC) ASTROCYTOMA. Histologically, it contains features of anaplasia such as hypercellularity, pleomorphism, nuclear hyperchromatism, and mitoses. Another characteristic feature of an anaplastic variety of astrocytoma is the proliferation of vascular endothelium. WHO GRADE IV ASTROCYTOMA (GLIOBLASTOMA MULTIFORME). Although its nomenclature means its origin from embryonal cells now it is known that this tumor arises by neoplastic transformation of mature astrocytes. Grossly, it shows variegated appearance, with some areas showing grey-white appearance while others are yellow and soft with foci of hemorrhages and necrosis. Histologically, the features are as under:- 1) It has a highly anaplastic and cellular appearance. ii) It shows areas of tumor necrosis around which tumour cells may form pseudopalisading. iii) Microvascular endothelial proliferation is marked. Ref: TEXTBOOK OF PATHOLOGY 6th EDITION - HARSH MOHAN PAGE NO:887-888
CP angle
Frontal lobe
Brain stem
Occipital lobe
Nervous system