[Pituitary adenoma calcification].

Three hundred and eighteen cases of functioning and non-functioning pituitary adenoma were examined by histological, immunocytochemical and electronmicroscopic technique. Fourty-four of them (13.8%) showed evidence of calcospherites in the tumor tissues. A high incidence of calcospherite is found in functioning adenoma, but not in non-functioning adenoma. Calcification was seen most frequently in cases of prolactinoma (23), GH secreting (7), or GH + PRL tumor (2) and less in adrenocorticotropic hormone secreting adenoma (2) and follicle stimulating hormone secreting adenoma (1). Prolactin and growth hormone might be involved in the control of calcium metabolism. This is because, following adenomectomy in patients with prolactinoma or GH-secreting adenoma with hypercalcemia, there is normalization of serum PRL and GH with reduction in serum calcium. Calcospherite is produced in all of metastatic calcification, arterial calcification, dystrophic calcification and calcinosis. In cases of non-functioning adenoma however, the mechanism is believed to by dystrophic calcification.