Adjuvant goserelin and ovarian preservation in chemotherapy treated patients with early breast cancer: results from a randomized trial

The purpose of this randomized study was to examine if goserelin concomitant to CMF-chemotherapy as adjuvant treatment for premenopausal breast cancer, protects the ovaries from premature failure. A total of 285 premenopausal breast cancer patients, in a randomized adjuvant trial (Zoladex in premenopausal patients (ZIPP)), were assigned to a study on ovarian function. Node positive patients were assigned to CMF-(cyclophosphamide, methotrexate and 5-fluorouracil) chemotherapy in addition to endocrine therapy. All patients were randomly assigned to receive 2 years of goserelin, goserelin plus tamoxifen, tamoxifen alone or no endocrine treatment. We studied, if menses were affected in the treatment groups, up to 36 months after randomization. One year after completed CMF- and endocrine therapy, 36% of the women in the goserelin group reported menses, compared to 7% in the goserelin plus tamoxifen group, 13% in the tamoxifen group and 10% of the controls. Among women treated with goserelin, there was a statistically significant increase in the proportion of menstruating women, 1 year after completed treatment compared to at 24 months of treatment (P = 0.006), in contrast to all other treatment groups, who were unchanged or more often amenorrheic. In our study, there is some evidence of protective effect of goserelin on ovarian function in CMF treated women. This effect was not observed in the combined tamoxifen and goserelin treatment.