Progestin receptors in meningiomas. Comparison of cytosolic assays with immunocytochemical identification in cryostat and paraffin sections.

The results are reported of ligand binding and enzyme immunoassays in tumour cytosols, and of immunoperoxidase assays in cryostat and paraffin sections measuring oestrogen (ER) and progestin receptors (PR) in 22 meningiomas and three non-meningioma tumours (two neurinomas and one haemangiopericytoma). With regard to the meningioma tissues, cytochemical immunoperoxidase PR-staining was present in all cryostat sections and in all but one of the paraffin sections. There was a good degree of qualitative accordance between all assay methods; they revealed the picture of "typical" meningioma: high PR and low ER. In this series, immunoperoxidase staining for the detection of PR-receptors, both in cryostat and paraffin sections, rendered encouraging results, thus offering a method for the detection of progestin receptors, which can compete with cytosolic methods.