33 SUSPECTED MIXED PITUITARY TUMOR IN A PATIENT WITH A PROLACTIN-SECRETING ADENOMA WITH MINIMAL SIZE RESPONSE TO CARBERGOLINE

• Published in: Journal of investigative medicine Vol. 54; no. 1; p. S261
• Main Authors: Seale, B. W., Subauste, J.
• Format: Journal Article
• Language: English
• Published: London Sage Publications Ltd 01.01.2006
• ISSN: 1081-5589; 1708-8267
• DOI: 10.2310/6650.2005.X0008.32

W.S. is a 61-year-old white male with a history of hypertension and type II diabetes mellitus, prior cholelithiasis, nephrolithiasis, and fatty liver who presented to the emergency department with hypoglycemia and shortness of breath. He was admitted to the internal medicine service and underwent workup that included a CT scan revealing honeycombing of the lung and hepatosplenomegaly. The patient was noted to be pancytopenic on presentation and found to have disseminated histoplasmosis. The patient subsequently began displaying signs of confusion, and a CT of his head was obtained. No evidence for spread of histoplasma infection was found; however, a large 3 3 3 3 2 cm mass was noted in the sella. A pituitary tumor workup ensued, and his prolactin level was found to be 6,141. No other pituitary markers were noted to be elevated. A formal MRI was obtained to more precisely measure tumor dimensions. The patient maintained a rather complicated, 40-day hospital course but was eventually discharged home. He was started on carbergoline 0.5 mg PO twice weekly for his prolactin-secreting tumor just prior to discharge. The patient maintained close follow-up and was noted to have a very good response to his carbergoline. Five months after initiation of the medication, the patient's prolactin level was noted to be normal (5.42). However, repeat MRI showed minimal change in tumor size. This could indicate that the tumor may be a mixed macroadenoma and not simply a prolactinoma as first thought. Five-month follow-up lab work demonstrated a free alpha-subunit that was twice the upper limits of normal, indicating a potential gonadotropin-secreting component. Diagnosis of a mixed pituitary tumor is actively being pursued in this patient.