Primary germinoma of the brain. Immunocytochemical demonstration of tumour cells in the cerebrospinal fluid.

A patient is presented, who developed a suprasellar tumour. Stereotactical biopsy of the tumour revealed the diagnosis of a dysgerminoma. Immunocytochemical examination of the CSF showed neoplastic cells staining for human chorionic gonadotropin and for alpha-fetoprotein. The authors stress the possibility to diagnose primary intracranial germ cell tumours without operation.