Prolactinoma

Prolactinomas represent approximately 40% of all pituitary adenomas, with a female preponderance.

Women usually present with amenorrhea and galactorrhea. Men may present with sexual dysfunction, hypogonadism, and sometimes gynecomastia, all related to the hyperprolactinemia.

Premenopausal women present earlier due to menstrual irregularity and hence usually have microprolactinomas. Men and postmenopausal women often present later with macroadenomas, which may be invasive or giant tumors.

Treatment with dopamine agonists usually results in prolactin normalization, symptom improvement, and tumor shrinkage.

Prolactinomas are benign lactotroph adenomas expressing and secreting prolactin.