Epidemiology and Management Challenges in Prolactinomas.

Clinically relevant pituitary adenomas are present in about 1 per 1,000 of the general population and prolactinomas are by far the most common clinical subtype of pituitary adenomas. Usually prolactinomas affect premenopausal women and present with typical symptoms of menstrual disturbance and/or galactorrhea. They are generally managed with dopamine agonists to restore fertility and to control symptoms and tumor size. In a subset of prolactinomas, however, management remains challenging. Studies in recent years have identified the factors related to dopamine agonist resistance, such as male sex, genetic features, and aggressive tumor behavior. Certain other patient groups represent particular challenges for management, such as pediatric patients and pregnant women. Treatment with dopamine agonists is usually safe and effective, and adverse effects such as clinically relevant cardiac valvular complications and impulse control disorders may occur in isolated instances. A number of important disease characteristics of prolactinomas remain to be explained, such as the difference in sex prevalence before and after menopause, the higher prevalence of macroadenomas in older males, and the biochemical mechanisms of resistance to dopaminergic agonists.