CLINICOPATHOLOGICAL STUDY OF 115 CASES OF GLIOBLASTOMA MULTIFORME WITH SPECIAL REFERENCE TO GLIOSARCOMA

Background: Glioblastoma Multiforme is the commonest of all astrocytomas. It accounts for 12-15% of all intracranial neoplasm and 50-60% of all astrocytic tumors. Most common site of occurrence is cerebrum and age incidence is highest in fifth and sixth decade. Gliosarcoma constitutes 2% of all brain tumors, 5% of all astrocytomas and 8% of anaplastic astrocytomas. The cell of origin of sarcomatous component has not been fully established.

Aim: The purpose of our study is to evaluate histopathological features of GBM in detail, in relation to the age, sex and site of occurrence, in Ganga Ram Hospital, during a period of 10 years and also to find out the relative frequency of Gliosarcoma among glial tumors. Particular emphasis is on to evaluate the nature of glial as well as mesenchymal component and their relationship in Gliosarcoma with the help of immunohistochemistry.

Materials: Total of 115 cases of Glioblastoma multiforme were studied histopathologically in detail, with some clinical corelation in Sir Ganga Ram hospital. 13 cases of Gliosarcomas, diagnosed morphologically as well as with the use of special immunohistochemical stains for sarcomatoid elements. This is a prospective as well as retrospective study between January 1995 and December 2005 Method: All the cases were examined M/E for cellularity, pleomorphism, mitosis, necrosis, haemorrhage, vascularity including endothelial proliferation and sarcomatous component. These features were graded subjectively into mild (+), moderate (++) and severe (+++). All the suspected sarcoma cases were confirmed by reticulin stain and then these Gliosarcomas were further analyzed with 5 more IHC stains like GFAP, ASMA, Desmin, FactorVIIIR/Ag and p53.

Results: All the Glioblastoma Multiforme cases were common in fifth and sixth decade with male to female ratio of 2.38:1. Common site of occurrence was cerebrum and the common clinical symptoms were headache, mental change and vomiting. Microvascular proliferation and gemistiocytic cell population was seen in variable amount in all cases.  Gliosarcoma were found to be common in males of 51-70yrs. Based on p53 staining, primary Gliosarcoma were found to be more common than the secondary ones. Analysis of the pattern of reticulin stain supports the vascular origin of Gliosarcoma. Factor VIII and ASMA positivity in sarcomatous area supports their origin from smooth muscle cell of vessel wall.