comparison of mib1 ki67 antigen and bromodeoxyuridine proliferation indices in meningiomas meningiomas from 40 adult patients were labeled immunohistochemically with monoclonal antibodies to bromodeoxyuridine budr and the ki67 antigen mib1 the meningiomas were classified as classical or benign n 31 atypical n 4 or malignant n 5 meningeal sarcomas and hemangiopericytomas were excluded the patient population consisted of 26 women and 14 men ranging in age from 26 to 75 years budr proliferation indices ranged from 0 to 58 measurements that were expectedly lower than those for mib1 which ranged from 15 to 193 mib1 proliferation indices were not significantly affected regarding steroid pretreatment or age these results show a good correlation between the budr and mib1 proliferation markers rs 072 p 0001 which supports the use of antimib1 as an alternative labeling tool to budr for the determination of the proliferation index in meningiomas thus avoiding the administration of a potentially mutagenic drug