Abstract

The grading of astrocytoma has traditionally relied on histological assessment, but there are some differences in their parameters, application, and reproducibility. Recently, numerous studies have attempted to correlate biological aggresiveness with tumor proliferation index using new immunohistochemical methods. The purpose of this study is to correlate the histopathological grades of astrocytoma with the expression of Ki-67, PCNA, p53 protein and AgNORs. The paraffin sections of 41 consecutive cases of astrocytomas were examined. Histologically the tumors were graded as three groups under the St. Anne-Mayo system and showed 14 cases in grade II, 15 cases in grade III and 12 cases in grade IV (glioblastoma multiforme). As a result, the Ki-67 labelling index and p53 protein expression tended to increase with increasing grade of malignancy. But the univariate analysis showed that there was no significant difference between the tumor grades (p>0.05). The PCNA labelling index and number of AgNORs revealed striking differences between the grade II and grade III astrocytomas (p<0.05). We concluded that the PCNA labelling index and AgNORs counting are useful markers for differentiation between grade II and III astrocytomas.

• Keywords: Astrocytoma;Ki-67;PCNA;AgNORs;p53 protein