From August 1986 to September 1988, 76 eligible patients with advanced prostatic carcinoma, measurable or evaluable disease, no previous hormonal treatment, were treated with Buserelin at a dosage of 500 micrograms every 8 h for 7 days, followed by 400 micrograms intranasally three times a day. No concomitant antiandrogens were administered. In the 63 evaluable patients (11 patients not yet evaluable because of short treatment time, two lost to follow-up), three complete remissions, 28 partial remissions, 30 stable disease and two progressions were obtained (National Prostatic Cancer Project criteria). Median duration of response was 55+ weeks. Side effects were modest, mostly related to the endocrinological effects of Buserelin. Transient increase in serum testosterone levels was found in 37% of the evaluable patients, but transitory 'flare-up' was present in seven patients only. With a median follow-up time of 11.5 months, median survival has not been reached. In conclusion, this study confirmed the activity of Buserelin and the feasibility of its middle-term administration.