Most often, PRL-secreting PAs occur sporadically, but up to 5% of cases develop as a component of the familial genetic syndrome, such as multiple endocrine neoplasia type 1 (MEN-1), MEN-4, Carney complex, familial isolated pituitary adenomas (FIPA) and familial pheochromocytoma/paraganglioma/pituitary adenoma (3PA) syndrome (66, 67). Here, PRL is linked to familial isolated pituitary adenoma.