Medical Castration with Zoladex: A Conservative Approach to Premenopausal Breast Cancer

Abstract

For almost a century surgical castration represented the initial standard therapy for metastatic breast cancer in premenopausal women with hormone dependent tumors. Today the suppression of ovarian function can also be obtained by the administration of supraphysiologic doses of luteinizing hormone releasing hormone (LHRH) agonists. From April 1987 to February 1989, 23 premenopausal patients with advanced breast cancer (median age 39 years, range 28-52, ER positive 20, unknown 3; prior chemotherapy 17) were treated with the LHRH agonist goserelin depot (Zoladex) at the dose of 3.6 mg. every 4 weeks. Twenty-two patients were evaluable. Serum levels of 17 β estradiol, progesterone, FSH and LH were suppressed by goserelin and fell to postmenopausal values within 8 weeks of therapy in 77 % of cases. Complete response (CR) plus partial response (PR) was documented in 7 of 22 (32 %) and occurred in all major sites of disease. Five patients achieved CR (soft tissue 3, viscera 2). Response rate was higher in patients not previously treated with chemotherapy (4/6). In the present series, all responses were seen in women > 35 years old, regularly menstruating at the start of treatment. Time to progression for the entire case series was 22 weeks and for responders 64 weeks. Oophorectomy was performed after disease progression in four patients without success. Goserelin was well tolerated. Local cutaneous dyschromia occurred in 45 % and hot flushes in 82 %. Treatment efficacy of goserelin is comparable to that of oophorectomy, without the psychological trauma and the morbidity related to surgical castration.