Nadir Prolactin–guided Individualized Cabergoline Therapy Achieves Durable Remission and Safe Pregnancy in Prolactinomas
Nobuhiro Miki, Masami Ono, Shun-ichiro Izumi, Tomokatsu Hori, Kayoko Abe, Takakazu KawamataAbstract
Context
Achieving durable prolactinoma remission while preserving safe pregnancy remains a central unmet goal of cabergoline therapy.
Objective
To prospectively evaluate individualized-dose cabergoline therapy for safe pregnancy, remission, and dosing optimization.
Methods
Women with 310 prolactinomas comprised 97 bromocriptine (BC)-resistant, 93 BC-intolerant, and 120 naïve patients, harboring 56 large macroprolactinomas (≥20 mm), 80 small macroprolactinomas (≥10 mm), and 174 microprolactinomas. Cabergoline dosing was individualized to maintain nadir prolactin within the lowest achievable normal range. In 129 macroprolactinomas and 19 microprolactinomas at risk of gestational enlargement, medical debulking prophylactically restored the optic–pituitary (O–P) distance to >5.0 mm before conception. Cabergoline was discontinued immediately after conception.
Results
Treatment achieved 100% biochemical normalization; 84–100% prepregnancy tumor debulking; 365 uneventful pregnancies in 294 patients (95%); no symptomatic tumor enlargement during pregnancy; and 72% postpartum remission overall (naïve 82%, BC-resistant 70%, BC-intolerant 61%; microprolactinomas 73%, macroprolactinomas 72%). Responder frequency was subtype-specific across 0.25–9.0 mg/week doses with distinct ED50 values ranging from 0.66 in BC-intolerant to 3.71 in BC-resistant patients. AIC-based multivariate analysis identified nadir prolactin—markedly lower in nonvisible than residual prolactinomas—as the dominant determinant of tumor disappearance. No cardiac valvulopathy or impulse control disorders were observed on longitudinal follow-up.
Conclusion
Despite marked ED50 heterogeneity, nadir prolactin–guided individualized-dose cabergoline therapy safely achieved durable remission with excellent pregnancy outcomes. These findings establish a clinically actionable, outcome-directed framework that prospectively integrates endocrine normalization, anatomical risk reduction, and tumor eradication, rendering durable remission and safe pregnancy realistically achievable therapeutic objectives in prolactinomas.