Case report: multiple intra-cranial metastases from a prolactin-secreting pituitary tumour.

Only seven cases of metastatic prolactin-secreting pituitary tumour have been reported in world literature. The metastases were intra-cranial in five cases and extra-cranial in two cases. We report a further case with multiple intra-cranial metastases in the supra-tentorial compartment. Histologically, both primary and metastatic tumours were benign with strongly positive immuno-histochemical staining for prolactin. Our case exemplifies the inconsistent correlation between the histopathological appearance and biological behaviour of malignant pituitary tumours.