Long-term LHRH-agonist treatment in metastatic breast cancer as a single treatment and in combination with other additive endocrine treatments.

Twenty-one premenopausal patients with metastatic breast cancer (unselected for receptor status) were treated during 3-14 months with the potent LHRH-agonist Buserelin (Hoe 766) as a first-line therapy. In one-third of 12 patients treated with Buserelin alone an objective tumour response was observed in the absence of side effects. The longest duration of response occurred in 2 patients with complete remissions (14+ and 13+ months). After addition and in combination with tamoxifen this LHRH-agonist treatment caused an objective response in about half (8/17) of the patients. A problem appears to be the great variation in hormonal response especially during the combination treatment with tamoxifen, which was not found during combination treatment with megestrol acetate in 4 patients. Ultimately, of the whole group of 21 patients, 9 patients (43%) showed an objective remission, 6 stable disease and 6 progression of tumour growth.