Abstract
Amyloid deposits in three functioning human pituitary adenomas (two prolactin (PRL) -secreting and one growth hormone (GH)-secreting) were studied by immunohistochemical techniques. Histological diagnosis was mixed pituitary adenoma in all cases. The amyloid deposits of all cases were negative for GH, AA protein, Aκ, Aλ, and γ-trace, but the amyloid deposits of two cases were strongly positive for PRL. Most cells surrounding amyloid were negative for all antibodies but a few cells were positive for PRL. From these findings, it was strongly suggested that the amyloid in pituitary adenoma is a kind of AE protein and of hormonal origin. Serum hormonal level, radiation, and bromocriptine therapies might not contribute to amyloid deposits.
