Progesterone and oestrogen receptors in meningiomas: biochemical and clinicopathological considerations.

Specific progesterone and oestrogen receptor proteins were evaluated by a dextran coated charcoal assay and Scatchard plot analysis in 20 intracranial meningiomas. Eleven tumours (55%) were progesterone receptor (PR) positive (mean 108 fmol/mg cytosol protein), whilst all were oestrogen receptor (ER) negative (ER less than 10 fmol/mg cytosol protein). There were no trends to suggest a relationship between epidemiological data (patient age, sex and reproductive status in females) or meningioma location and size and the receptor status of the tumour. However, of the seven meningiomas that were histologically atypical, invasive or clinically recurred within 18 months, six were PR negative (PR less than 10 fmol/mg cytosol protein). These results confirm that a large proportion of intracranial meningiomas contain significant amounts of specific PR protein and suggest that PR negative meningiomas are biologically more aggressive than PR positive meningiomas. They are also consistent with the hypotheses that PR proteins are not modulated by oestrogens acting through oestrogen receptors and that there are cytokinetic differences between sex hormone receptor proteins in meningioma and breast carcinoma. The full biochemical, cytological and clinical implication of these preliminary findings will, however, require further evaluation because of the unpredictable long-term behaviour of intracranial meningiomas.