Effects of Pituitary Surgery and High-Dose Cabergoline Therapy on Metabolic Profile in Patients With Prolactinoma Resistant to Conventional Cabergoline Treatment

The aim was to formulate practice guidelines for the diagnosis and treatment of hyperprolactinemia. The Task Force consisted of Endocrine Society-appointed experts, a methodologist, and a medical writer. This evidence-based guideline was developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe both the strength of recommendations and the quality of evidence. One group meeting, several conference calls, and e-mail communications enabled consensus. Committees and members of The Endocrine Society, The European Society of Endocrinology, and The Pituitary Society reviewed and commented on preliminary drafts of these guidelines. Practice guidelines are presented for diagnosis and treatment of patients with elevated prolactin levels. These include evidence-based approaches to assessing the cause of hyperprolactinemia, treating drug-induced hyperprolactinemia, and managing prolactinomas in nonpregnant and pregnant subjects. Indications and side effects of therapeutic agents for treating prolactinomas are also presented.

New information about the effects of prolactin (PRL) on metabolic processes warrants re-evaluation of the overall metabolic actions of PRL. PRL affects metabolic homeostasis by regulating key enzymes and transporters that are associated with glucose and lipid metabolism in several target organs. In the lactating mammary gland, PRL increases the production of milk proteins, lactose and lipids. In adipose tissue, PRL generally suppresses lipid storage and adipokine release. PRL supports the growth of pancreatic islets, stimulates insulin secretion and increases citrate production in the prostate. A specific case is made for PRL in the human breast and adipose tissue, where it acts as a circulating hormone and an autocrine or paracrine factor. Although the overall effects of PRL on body composition are modest and species specific, PRL might be involved in the manifestation of insulin resistance.