The evolving role of androgen deprivation therapy in the management of prostate cancer.
Androgen deprivation therapy (ADT) plays a central role in the management of prostate cancer. ADT is the mainstay of treatment for metastatic disease; the most common method is gonadal suppression via luteinizing hormone release hormone (LH) agonists, with or without antiandrogens. Antiandrogen monotherapy remains investigational, as is the appropriate role of 5alphareductase inhibition for prostate cancer. Intermittent ADT offers the promise of improved quality of life and reduced cost without a decrease found to date in oncologic efficacy. A growing menu of options exists for secondary androgen deprivation after disease progression on primary therapy: these include high-dose antiandrogens, estrogens, and adrenal androgen suppressants. ADT is being used with increasing frequency as primary monotherapy in patients with localized disease, but only small, nonrandomized studies of highly selected patients have been reported to date. Neoadjuvant ADT (NADT) has been demonstrated in prospective, multi-institutional trials to improve outcomes for patients with high-risk or locally advanced disease undergoing external-beam radiotherapy. Trials for patients with lower-risk, localized disease are still ongoing. Neoadjuvant therapy does not improve outcomes for patients with localized disease opting for radical prostatectomy (RP) and has not been well studied in association with brachytherapy. The side effects of ADT can be managed increasingly successfully; in particular, the introduction of zoledronate may reduce the impact of ADT-associated osteoporosis. Finally, contemporary practice pattern data suggest that use of ADT is increasing across patient risk groups, both in contexts where such therapy is well supported by current evidence and in others where it is not.