Sustained suppression of testosterone production by the luteinising-hormone releasing-hormone agonist buserelin in patients with advanced prostate carcinoma. A new therapeutic approach?

Nine patients with advanced carcinoma of the prostate were treated with the luteinising-hormone-releasing-hormone agonist buserelin (2 mg/day subcutaneously for 3 days then 0.4-1.2 mg/day intranasally for up to 24 weeks). There was a rise in luteinising-hormone levels during the first few days of treatment, but levels fell after 3 weeks and remained lower than normal after 24 weeks' treatment. In patients receiving 0.6-1.2 mg buserelin per day testosterone levels fell to less than 1 ng/ml within 3 weeks and were still as low as those found in surgically castrated men after 24 weeks. Histology showed regressive changes in some tumours after 3-6 months' buserelin treatment similar to those seen in surgically castrated men. Buserelin treatment may be an alternative to surgery in patients with advanced carcinoma of the prostate.