Endocrine Abstracts

Background and Objective

Data on the epidemiology, effects of dopamine agonists and long term outcome of prolactinoma in children and adolescents have been gradually accumulating but are still scarce. We conducted a systematic review and meta-analysis of published literature (1994 – 2019) to study the epidemiology of prolactinoma in patients < 20 years old, and determine the management strategies adopted.

Methods: Relevant studies were identified through Medline search and from the reference list of retrieved studies. Pertinent data were extracted. Both “random” and “fixed” effects meta-analysis were used to pool outcomes across studies.

Results: Of 635 articles retrieved, 610 were discarded during the title and abstract analysis. Another seven articles were excluded after full-text analysis as they did not report on our research questions. A total of 18 articles, describing 487 patients, were then reviewed. A pronounced sex difference was noted with 75.7% (95% CI 69.6 to 81.3%) of patients being female. Patients were divided into those with macroprolactinoma (n = 288), microprolactinoma (n = 151) and size not specified (n = 48). After excluding one large series which reported only macroprolactinomas, the proportion of patients with macroprolactinomas (57.6% [95% CI 51.2% to 64.0%]) was still higher than with microprolactinomas. Both macroprolactinomas (134 vs 67 F:M) and microprolactinomas (137 vs 6 F:M) were more common in females as compared to males. Even more striking was the difference in the distribution of size (micro/macro) between the two sexes. In males, only 6/73 (8.2%) of tumours were microprolactinoma as compared to 137/271 (50.5%) in females (risk difference 0.463; [95% CI 0.386 to 0.541]; P < 0.001). Medical or surgical therapy was adopted as first-line therapy in 67.4% and 32.6% respectively. Surgery was, surprisingly, the initial treatment in 87/273 (31.9%) with macroprolactinoma, and 26/126 (20.6%) with microprolactinoma. In patients where the initial treatment was medical, 45/186 (24.2%) of macroprolactinoma patients and 20/100 (20%) of microprolactinoma patients subsequently proceeded to surgical intervention. Growth hormone, Adrenocorticotrophic hormone, Thyrotropin and Arginine Vasopressin deficiency were reported in 39 (8.7%), 43 (9.6%), 47 (10.5%) and 15 (3.3%) patients respectively (inadequate data to qualify whether pre- vs post-surgery.

Conclusions: Microprolactinoma occurs almost exclusively in females and is an uncommon diagnosis in males in this age group. Macroprolactinoma is also more common in girls compared to boys. A surprising number of patients proceeded to surgery before medical therapy, and surgery is part of overall management in a substantial proportion. Association with other pituitary hormone deficienciesis not uncommon.