Natural history of microprolactinomas: six-year follow-up.

A 6-year follow-up of patients harboring microprolactinomas suggests that few patients (3 of 27) demonstrate significant growth of their tumor during this time. The major hazard for such patients who are not treated seems to be their risk for the development of premature osteoporosis in the face of sustained hyperprolactinemia. The risks of this complication may exceed the risks of early surgical intervention in selected patients. This short term risk of tumor growth (about 10%) must be weighed in the decision about therapeutic endeavors.