A prolactinoma is a non-cancerous swelling in the pituitary gland, which makes too much of a hormone called prolactin. This can cause various symptoms including reduced fertility, breast changes, and headaches. In children there may be reduced growth or delayed puberty
Pathophysiology: Tumor formation is due to neoplastic transformation of anterior pituitary lactotrophs, resulting in excess synthesis and secretion of prolactin (PRL). Linkage to aryl hydrocarbon-interacting protein gene (AIP) mutation has been identified in some families with prolactinoma and in childhood-onset pituitary adenomas.
Symptoms: When prolactin levels get increased there will be no periods, milk production will occur (infrequent in men), loss of axillary and pubic hair and Small gonads, gynecomastia, erectile dysfunction (in males). When there is mass effect then, bitemporal hemianopsia (due to pressure on optic chiasm), vertigo, nausea, vomiting are the symptoms.