An update on ovarian suppression/ablation

Abstract

Adjuvant ovarian function suppression is acknowledged today as effective therapy for premenopausal patients with early breast cancer. Various modalities have been applied to achieve this treatment option: First, early investigations comparing ovarian ablation with chemotherapy identified similar outcomes in terms of patients' rates of disease-free survival (DFS). Second, prospective randomized trials have more recently focused on luteinizing hormone-releasing hormone analogues (LHRHa) that induce medical ovarian suppression and avoid the morbidity and irreversibility associated with surgical ovariectomy or irradiation. These trials analyzed the value of treatment with goserelin or other LHRHa, with or without tamoxifen, as against chemotherapy. Goserelin was subsequently established as a valid alternative, and our own results demonstrated that goserelin + tamoxifen is more effective and better tolerated in hormone-responsive patients. Third, other multiple-arm studies have compared LHRHa + chemotherapy with chemotherapy alone. Addition of tamoxifen to goserelin + chemotherapy was shown to improve DFS, and significant benefits in goserelin-treated patients were seen irrespective of use of chemotherapy or tamoxifen. Finally, ongoing trials are addressing the appropriate duration of LHRHa therapy and other unresolved issues. In summary, combined ovarian suppression with adjuvant goserelin and tamoxifen is considered to be at least as effective as chemotherapy in premenopausal breast cancer patients. Published reports have demonstrated that ovarian suppression is a safe means of reducing risk of recurrence in estrogen receptor-positive women and underlined its use as a competitive alternative to chemotherapy in this patient subset.