ARGUMENTS AGAINST THE LONG-TERM USE OF COMBINED ANDROGEN BLOCKADE

Androgen deprivation therapy is the most effective systemic treatment for advanced prostate cancer. However, as most patients who die from p rostate cancer have hormone refractory disease, fine tuning of antiand rogen treatment by combined androgen blockade (CAB) can not be expecte d to improve survival significantly. Only the South West Oncology Inte rgroup (SWOG) study 0036 has shown a significant advantage for CAB com pared with luteinizing hormone-releasing hormone (LH-RH) agonist alone . However, the results of this study should be interpreted with cautio n as the patients had to self-administer their treatment by daily inje ction so compliance may not have been optimal. Also, those receiving L H-RH agonist alone were not covered against disease flare. Indeed, no trial using depot LH-RH agonist with or without flutamide has been abl e to show a survival benefit. When treatment with LH-RH agonist plus a ntiandrogen was compared with orchiectomy alone, only the European Org anization for Research and Treatment of Cancer (EORTC) study 30853 sho wed a significant difference in favour of CAB. However, in this study an increased proportion of patients receiving CAB may have had a more favourable prognosis. Only one study comparing orchiectomy plus antian drogen with orchiectomy alone has shown an advantage for CAB therapy, and this was only slight. Therefore, as yet there is no justification for long-term use of CAB. However, short-term antiandrogen treatment m ust be used to prevent disease flare during initiation of LH-RH agonis t treatment.