PROLIFERATIVE POTENTIAL OF MENINGIOMAS EVALUATED BY PROLIFERATING CELL NUCLEAR ANTIGEN EXPRESSION

Meningiomas are principally benign in nature. Some meningiomas, howeve r, grow fast or recur even after total removal. The biological behavio r of meningiomas often can not be predicted from conventional histopat hological studies. A monoclonal antibody against proliferating cell nu clear antigen (PCNA) was used to investigate the usefulness of the PCN A index as a parameter to estimate the proliferative activity of menin giomas. Fifty-two meningiomas were examined. The mean PCNA index of re current meningiomas (3.37 +/- 0.92%) was significantly higher than tha t of non-recurrent meningiomas (1.12 +/- 0.51%) (p < 0.005). The PCNA indices of recurrent cases were all higher than 2.0%. A semilog linear regression analysis between tumor doubling time and PCNA index showed a significant correlation (r = 0.90, p < 0.05). An inverse linear cor relation between PCNA index and interval to recurrence was observed (r = 0.62, p < 0.05). A good linear correlation was also shown between P CNA index and BUdR labeling index (r = 0.88, p < 0.01). The results of this study suggest that, providing the methods of tissue processing, immunostaining and counting of positive nuclei are unified, the PCNA i ndex is a useful parameter for estimating the biological behavior of m eningiomas.