Pituitary Apoplexy in Long-Term Cabergoline User During Thrombocytopenia Due to Chemotherapy for Chronic Myelocytic Leukemia.

BACKGROUND: Pituitary apoplexy (PA) is a life-threatening syndrome. The usage of a dopamine agonist, such as bromocriptine or cabergoline, is considered a predisposing factor for PA, which commonly occurs 1.5 years within commencement.

CASE DESCRIPTION: A 64-year-old female with a >15-year history of cabergoline therapy for pituitary prolactinoma was referred to our department of neurosurgery after complaining of headache, blurred vision, diplopia, and ptosis for 3 days during hospital admission for chemotherapy of chronic myelocytic leukemia. Computed tomography and magnetic resonance imaging revealed findings indicative of PA. As the patient was experiencing thrombocytopenia related to chemotherapy, blood transfusion was preceded, and after a platelet count of 15.0 × 104/μL was confirmed, transnasal neuroendoscopic surgery was performed 5 days from the onset of symptoms. The majority of the prolactinoma was removed, and the prolactinoma in the cavernous sinus was intentionally left. The postoperative course was generally good. The ptosis and diplopia improved, and the blurred vision resolved.

CONCLUSIONS: PA related to dopamine agonist therapy can occur in cases of elevated bleeding tendency, even in long-term users, suggesting that attention should be paid in the administration of a dopamine agonist in the patient experiencing thrombocytopenia. Surgical intervention should be performed after the preoperative platelet number and adequate response to transfusion are confirmed, and the aggressive removal of prolactinoma in the cavernous sinus should be avoided to reduce the risk of hemorrhagic complications.