Thirteen patients with advanced adenocarcinoma of the prostate were treated with buserelin-a gonadotropin-releasing hormone (GnRH) analogue. Follow-up period extended to thirty-six months during which 8 patients were considered either responsive or stabilizing, in terms of pain relief and clinical tumor regression, and 5 were categorized as suffering from progressive disease. Urinary symptoms were ameliorated in the majority of cases (11/12). Prostatic size was measured by rectal ultrasound, an accepted accurate new modality. In 12 patients a decrease in size was demonstrated, and only in 1 progressive case the prostate grew larger on a six-month follow-up. Thus prostatic size and clinical responsiveness are not correlated. The clinical value of recording urinary symptomatology and measuring prostatic size in prostatic carcinoma patients is discussed with regard to the latest communications that GnRH analogues acting by decreasing testosterone levels, can cause amelioration in benign prostatic hypertrophy (BPH) cases, too. It is suggested that prostatic size has little clinical value concerning tumor responsiveness in the follow-up of patients with prostatic carcinoma.