Late presentation of acromegaly in medically controlled prolactinoma patients

• Main Authors: Ekaterina Manuylova, Laura M Calvi, Catherine Hastings, G Edward Vates, Mahlon D Johnson, William T Cave Jr, Ismat Shafiq
• Format: Article
• Language: English
• Published: Bioscientifica 2016-10-01
• Series: Endocrinology, Diabetes & Metabolism Case Reports
• Online Access: https://www.edmcasereports.com/articles/endocrinology-diabetes-and-metabolism-case-reports/10.1530/EDM-16-0069

Co-secretion of growth hormone (GH) and prolactin (PRL) from a single pituitary adenoma is common. In fact, up to 25% of patients with acromegaly may have PRL co-secretion. The prevalence of acromegaly among patients with a newly diagnosed prolactinoma is unknown. Given the possibility of mixed GH and PRL co-secretion, the current recommendation is to obtain an insulin-like growth factor-1 (IGF-1) in patients with prolactinoma at the initial diagnosis. Long-term follow-up of IGF-1 is not routinely done. Here, we report two cases of well-controlled prolactinoma on dopamine agonists with the development of acromegaly 10–20 years after the initial diagnoses. In both patients, a mixed PRL/GH-cosecreting adenoma was confirmed on the pathology examination after transsphenoidal surgery (TSS). Therefore, periodic routine measurements of IGF-1 should be considered regardless of the duration and biochemical control of prolactinoma.