Multicenter Study of Prolactinoma Patients with Prior Dopamine Agonist Therapy and subsequent Transsphenoidal Surgery: Insights into Demographics, Treatment, and Outcomes

Introduction: Prolactinomas are common pituitary tumors, often managed initially with dopamine agonist (DA) therapy. However, some patients need transsphenoidal surgery (TSS) after initial trial of pharmacological therapy. This multicenter study offers a descriptive analysis of the patient demographics, tumor characteristics, treatment approaches, and outcomes.

Methods: 96 patients who underwent TSS after initial DA therapy for prolactinoma at the three Mayo Clinic Campuses were retrospectively reviewed. Clinical data including patient characteristics such as age, gender distribution (45.8% male, 54.2% female), and tumor specifics, such as macroadenoma presence (72.9%), cavernous sinus invasion (33.4%), extensions into suprasellar (42.7%), anterior fossa (11.5%), and posterior fossa (6.3%) were collected. Additionally, the study details the reasons for TSS, DA type (Bromocriptine, 9.6%; Cabergoline, 90.4%), and survival status (alive; 96.9%, deceased; 3.1%).

Results: The median age of the patients were 36.5 years (ranging from 16 to 82 years), with pre-op prolactin levels (median: 102 ng/mL, range: 4-7291 ng/mL). Median postoperative prolactin levels on the first day was 13.65 ng/mL, slightly increasing to 16 ng/mL during follow-up. We observed a median post-op prolactin drop of 78.5 ng/mL. Notably, 60.4% of patients achieved remission (post-op prolactin < 20 ng/mL) with 32.3% requiring postop DA therapy. Reasons for TSS included medication intolerance (41.5%), medication failure (no response to DA therapy; 20.7%), medication resistance (initial response to DA therapy without achieving biochemical remission; 17%), optic chiasm compression (9.8%), recurrence of hyperprolactinemia (8.5%), and cerebrospinal fluid leak due to DA (2.5%).

Conclusion : This study underscores the significance of recognizing specific prognostic factors leading to TSS in prolactinoma patients with prior pharmacological therapy. It highlights the importance of individualized clinical decision-making and management strategies in such cases. By identifying these key factors, healthcare professionals can refine their approach to improve patient outcomes and quality of care in the management of prolactinoma.