MON-070 A Rare Case of Bilateral Recurrent Galactoceles In a Woman with Prolactinoma

Abstract Disclosure: M.W. Ansari: None. B. Barthel: None. Background: Prolactinomas are common pituitary adenomas which secrete excess prolactin. Galactoceles, typically associated with lactation1, are rarely reported in patients with prolactinoma. This case highlights bilateral galactocele formation in a 39-year-old African American female with a longstanding history of prolactinoma and hyperprolactinemia. Clinical Case: The patient was diagnosed with prolactinoma in 2017 as an incidental finding on brain MRI. She initially presented with migraines, amenorrhea, and galactorrhea. An MRI scan revealed an 8mm microadenoma, and her prolactin level was found to be 100 ng/mL. She was started on bromocriptine but discontinued it in 2018 due to a potential drug interaction, leading to a prolactin increase to 107.1 ng/mL in spring of 2019. Subsequent MRIs in 2019 and 2021 showed a stable 1cm borderline macroadenoma. Bromocriptine (2.5mg daily) was restarted in 2019. Despite dose increases, prolactin levels fluctuated, reaching 140.7 ng/mL in June 2020 before normalizing to 28.99 ng/mL in July 2020.In 2022, the patient became pregnant and her bromocriptine was stopped. Postpartum, prolactin levels remained elevated (73 ng/mL), and cabergoline was initiated in July 2023 at 0.5mg twice weekly, which was later increased to three times weekly for better control as this is the preferred first line therapy. In February 2024, she presented with a left breast lump; ultrasound (US) revealed a well-circumscribed 8cm mass with internal debris and calcifications, consistent with a benign galactocele. An aspiration was performed in April 2024 and removed 130mL of milky fluid which relieved symptoms temporarily, but recurrence was noted within two months. She was switched over to bromocriptine in April, as she had success earlier with this medication to control her prolactin level.In August 2024, bilateral galactoceles were identified, confirmed via US (left: 7.5cm, right: 3.7cm). She had another aspiration in August which removed 240mL (left) and 25mL (right) of milky fluid. Prolactin levels, controlled with bromocriptine 7.5mg, later required escalation to 10mg and, most recently, 15mg daily. Prolactin trends revealed persistent elevation despite treatment (2025: 82.65 ng/mL). Clinical Lessons: This case underscores bilateral galactocele formation as a rare prolactinoma complication. Further management of the patient beyond lowering prolactin levels with dopamine agonist may need to be pursued in these cases. Further research is needed to elucidate prolactin’s role (duration/degree of elevation) in galactocele formation and re-accumulation, as well as optimizing management strategies. References:1.Chiu et al., Galactocele in Nonlactating Women: A Case Report and Literature Review, Breast J, 2013. Presentation: Monday, July 14, 2025