Optimal effective doses of cabergoline and bromocriptine and valvular leasions in men with prolactinomas

Prolactinoma is the most common pituitary adenoma, and dopamine agonists( BRC, and CAB) is the primary therapy. Recently, the increased prevalance of cardiac valvular disease in patients treated with DAs for Parkinson's disease has raised concerns about the safety of this drug in patients with prolactinoma. CAB and pergolide are frequently reported to cause valvulopathy, there are very few studies showing this side effect in BRC administiration which has less potent agonism of 5-HT2B receptors. Male patients who are known to have higher prevalance of macroadenomas compared to women. The dosage of DAs administered were rarely evaluated.

We performed a retrospective chart to evaluate the medical management and treatment outcomes of male patients with macro/giant prolactinomas. We evaluated 22 patients with prolactinoma managed with DAs therapy alone for at least 1 year. All patients were followed for a mean of 61 months. Pretreatment echocardiographic examination were not available at that time.

None of them had any resistance or intolerance to DAs. The mean tumor shrinkage was 62%. In three patients the macroprolactinoma disappeared, in two patients the tumor shrinkage was 93% and 70%. The DAs therapy was discontinued in these patient. After a follow up neither MRI showed a recurrence or enlargement of the adenoma, nor prolactin levels showed any elevation. The echocardiography were performed at the last visit of each patient and no valvulopathy in any of the patients on DAs therapy were detected.

DAs are effective, and safe for valve morphology with mean cumulative doses of 155 mg CAB, and 7 301 mg BRC in patients with macroprolactinoma.