Treatment with a luteinising-hormone-releasing-hormone analogue (buserelin) in premenopausal patients with metastatic breast cancer.

Four premenopausal women with metastatic breast cancer were treated with a potent luteinising-hormone-releasing-hormone (LHRH) analogue as a single first-line agent. Buserelin (6-D-ser-(but(-LHRH-(1-9)-ethylamide) was given in very high dose intravenously and then intranasally; ovarian function did not decrease within 1-2 weeks, but after this period low to very low (postmenopausal) plasma oestradiol levels were reached in all patients, accompanied by flushes. Two patients, however, subsequently showed transient peaks of plasma oestradiol, probably due to a persistent follicle, which lasted for some weeks without a rise in plasma luteinising hormone, follicle-stimulating hormone, or progesterone. In two patients there was a significant change in the tumour, whereas in the other two patients there was remarkable improvement.