RECURRENCE OF MENINGIOMAS VERSUS PROLIFERATING CELL NUCLEAR ANTIGEN (PCNA) POSITIVITY AND AGNOR COUNTING

Meningiomas have a wide range of biological potential and clinical beh aviour. Histological findings are helpful in recognizing the malignant potential but often fail to correlate with clinical behaviour. This s tudy attempts to correlate the silver nucleolar organizer regions (AgN ORs) and proliferating cell nuclear antigen (PCNA) with clinicopatholo gical features of biological activity. Thirty-four completely resected meningiomas were classified as benign [19], atypical [6] and malignan t [9]. Forty-eight initial and recurrent tumour materials were investi gated for staining of AgNORs and immunohistochemistry using monoclonal antibodies against PCNA (clone 19A2 and PC10). There were no differen ces between the recurrent and non-recurrent cases with regards to AgNO R, PC10 and 19A2 values. Also, no significant difference was found bet ween the primary and recurrent tumours. Both PC10 and 19A2 labelling i ndices (LI) showed a significant difference between benign and maligna nt meningiomas. The 19A2 LI was 0.56 plusminus 0.21 in benign and 2.45 plusminus 16 in atypical meningiomas. The 19A2 counts showed signific ant difference between benign and atypical tumours but PC10 values fai led to show such a correlation. AgNOR and PCNA indices were not found to be useful in predicting recurrences compared to the surgical proced ure and histopathological criteria.