Impact of menopause on outcomes in prolactinomas after dopamine agonist treatment withdrawal.

OBJECTIVE Discontinuation of dopamine agonist (DA) treatment in women with prolactinoma after menopause is a potential approach; studies systematically assessing long-term outcomes are lacking. Our aim was to investigate the natural history of prolactinoma in this group. DESIGN/PATIENTS Retrospective cohort study of women with prolactinoma diagnosed before menopause and who after menopause were not on DA. RESULTS Thirty women were included. Twenty-eight received DA (median duration 18 years, median age at DA withdrawal 52 years). At last assessment (median follow-up 3 years) and compared with values 6-12 months after stopping DA, Prolactin (PRL) increased in 15%, decreased but not normalized in 33% and was normal in 52%; PRL levels or visible adenoma on imaging before DA withdrawal, treatment duration and presence of macro-/microadenoma at diagnosis were not predictors of normoprolactinaemia at last review, whereas PRL values 6-12 months after stopping DA were. Adenoma regrowth was detected in 2/27 patients (7%), who showed gradual increase in PRL. Comparison with 28 women who had DA withdrawal before their menopause revealed lower risk of hyperprolactinaemia recurrence in the postmenopausal group (HR:0.316, 95% CI: 0.101-0.985, P < .05). Two women with microprolactinoma diagnosed in perimenopausal period had not been offered DA; PRL decreased (but not normalized) during observation of 1 and 8 years. CONCLUSIONS Prolactin normalized over time in nearly half of the women and serum PRL 6-12 months after DA withdrawal is useful predictor. Nonetheless, 7% of the patients demonstrated adenoma regrowth which, given the life expectancy postmenopause, necessitate regular monitoring of the cases with persistent hyperprolactinaemia