Which type of pituitary tumor is commonly associated with increased prolactin levels?

Prolactinomas are the most common type of pituitary adenoma and are characterized by the overproduction of the hormone prolactin. These tumors arise from lactotrophs, the pituitary cells responsible for synthesizing and secreting prolactin. Increased levels of prolactin can lead to various clinical manifestations, including galactorrhea (milk production), amenorrhea (absence of menstrual periods), and infertility in women, as well as decreased libido and erectile dysfunction in men.

The presence of a prolactinoma is significant because it often leads to specific symptoms due to hyperprolactinemia, which can be diagnosed through serum prolactin tests. Management typically involves medical therapy with dopamine agonists, which effectively reduce prolactin levels and can often shrink the tumor.

Although other pituitary adenomas produce different hormones—gonadotroph adenomas produce luteinizing hormone (LH) and follicle-stimulating hormone (FSH), corticotroph adenomas produce adrenocorticotropic hormone (ACTH), and thyrotroph adenomas produce thyroid-stimulating hormone (TSH)—none of these typically result in increased prolactin levels, making prolactinoma the definitive association for elevated prolact