In this series the proliferation rate was measured by immunohistochemical examination with MIB-1 antibody, used as a marker for tumor proliferative potential, where MIB-1 of 2.7% was found for intracranial meningiomas located in other than the skull base, meanwhile, skull-base meningiomas rate was 2% (p 0.0013), these differences are statistically significant [22-23]. This evidence concerns the gene MIB1 and intracranial meningioma.