Medical castration produced by the GnRH analogue leuprolide to treat metastatic breast cancer.

Leuprolide (Lupron, TAP Pharmaceuticals, North Chicago), a gonadotropin-releasing hormone analogue, was administered to 26 premenopausal women with metastatic breast cancer. Of 25 evaluable patients, 11 (44%) had a partial response with a median duration of 39 weeks and five (20%) remained stable. Six patients showed early rapid progression of their disease. Toxicity was mild and included hot flashes, nausea, vomiting, and headache. Leuprolide induced amenorrhea in all patients who received treatment for ten weeks or longer. We conclude that this GnRH analogue provides a safe and effective means of producing medical castration in premenopausal patients with metastatic breast carcinoma.