Prolactinomas diagnosed in the postmenopausal period: clinical phenotype and outcomes

Objective: Most prolactinomas in females are diagnosed during the reproductive age, and the majority are microadenomas. Prolactinomas detected in the postmenopausal period are less common with limited published data on their presentation and prognosis. Our objective was to assess the presenting clinical, biochemical and imaging findings, as well as the outcomes of women diagnosed with a prolactinoma in the postmenopausal period.

Design and methods: We undertook a retrospective cohort study of women diagnosed with prolactinoma after menopause and followed up in a large UK pituitary centre. Information on presentation, management and outcomes was collected.

Results: Seventeen women with a median age at diagnosis of 63 years (range 52-78) were identified. Headaches and/or visual deterioration were the most commonly reported complaints at detection of the adenoma (47%). Acute pituitary apoplexy was diagnosed at presentation or during follow-up in 18% of the cases. The median serum prolactin was 12 364 mU/L (range 2533-238 479). Macroprolactinomas comprised 94% of the tumours, and 88% of them had supra/parasellar extension. All patients with macroprolactinoma were offered dopamine agonist, and normal prolactin was achieved in 94% of them (median follow-up 91.5 months). Adenoma shrinkage was observed in all women. Improvement or resolution of visual disturbances documented at presentation was observed in 86% of cases.

Conclusions: The clinical phenotype of prolactinomas diagnosed in the postmenopausal period is characterized by dominance of macroadenomas, with frequent supra/parasellar extension and a relative high rate of acute pituitary apoplexy. In this group of patients, the response of the macroadenomas to dopamine agonists is good.