[Hyperstosis in patients with intracranial meningioma--secondary changes in tumor invasion].

A comprehensive clinical, histological, and immunohistochemical evaluation was done of 42 intracranial meningiomas in patients with hyperostosis in the postoperative period. It has been ascertained that hyperostosis in meningiomas is a direct bone tumour invasion. Bone invasion is not a sign of malignant transformation of meningiomas. It is shown that meningiomas with hyperostosis are hormone-dependent tumours. In tumours, there has been detected a high concentration of progesterone and estrogen active receptors. It is shown that hyperostosis is a consequence of hormone-related abnormalities of Ca metabolism. Special stress is laid on ridding the bone of hyperostosis at tumour removal to reduce the number of tumour recurrences.