Proliferative Potential of Malignant and Non-Malignant Meningiomas

Meningiomas are common neoplasms in the central nervous system. Although most of these tumors are encapsulated and grow very slowly, some meningiomas invade into adjacent brain tissue and skull, grow faster, and recur more frequently than classic meningiomas. These malignant meningiomas, however, are not well defined histopathologically, and their biological characteristics have never been well documented. We studied the cell kinetics of human meningiomas immunohistochemically using a monoclonal antibody against bromodeoxyuridine (BUdR) (2), a thymidine analogue that is incorporated into nuclear DNA during the synthesis phase of the cell cycle. BUdR-labeled S-phase cells can be identified by anti-BUdR monoclonal antibodies, which can then be detected by indirect immunoperoxiase methods (3, 6).