Management of advanced prostate cancer: can we improve on androgen deprivation therapy?

Gonadotrophin-releasing hormone (GnRH) agonists are currently the mainstay in the management of advanced prostate cancer. Used either as monotherapy or combined with antiandrogens, GnRH agonists suppress serum testosterone levels and thus slow the growth of the tumour cells that depend on testosterone for growth. GnRH agonists have largely replaced orchidectomy in the management of advanced prostate cancer, because patients are reluctant to undergo surgical castration. However, can we do better in androgen-deprivation therapy? There is some evidence to suggest that GnRH agonists do not achieve the level of testosterone suppression attained with orchidectomy, or as rapidly, factors which could be expected to affect overall survival. Together, these observations highlight the need to develop newer agents that can achieve rapid, profound and sustained testosterone suppression, equivalent to that with orchidectomy. Preliminary data for the GnRH blocker, degarelix, suggest that this new agent might overcome the shortcomings associated with GnRH agonists. Further clinical data are therefore awaited with much interest.