A Pilot Phase Ii Trial Of Cabergoline In The Treatment Of Metastatic Breast Cancer.

e12568Background: The prolactin receptor can be overexpressed in breast cancer, and pre-clinical data indicate that it contributes to the pathobiology of breast cancer. Cabergoline is a potent dopamine receptor agonist of D2 receptors and has a direct inhibitory effect on pituitary prolactin secretion resulting in reduced serum prolactin levels. Methods: A pilot phase II study of cabergoline in patients with metastatic breast cancer was conducted with primary end point of best overall response rate (ORR) among patients with measurable disease. Eligible patients had metastatic breast cancer, any receptors status was allowed, and there was no limit of prior lines of therapy. Both measurable and unmeasurable diseases (RECIST 1.1) were allowed. Cabergoline 1mg orally, twice weekly (1 cycle = 4 weeks) was given until disease progression or unacceptable toxicity. Immunohistochemistry prolactin receptor staining was performed on available baseline tumor tissue, and serum prolactin levels were serially assessed. ...