The role of androgen deprivation in the definitive management of clinically localized prostate cancer treated with radiation therapy

Purpose: Multiple studies exploring the use of androgen deprivation given i n combination with radiotherapy (RT) for localized prostate cancer have rep orted significant improvements in the rates of local, regional, and biochem ical control (BC). The impact of this therapeutic strategy on overall and c ancer specific survival (CSS) has not been established, however. We perform ed a MEDLINE search of all available studies on this topic to determine if any conclusions could be reached on the efficacy of this treatment approach and the patients most suitable for its application. Materials and Methods: A MEDLINE search was conducted to obtain all article s in the English;language on the use of androgen deprivation in combination with RT for the treatment of localized prostate cancer. The medical subjec t headings (MeSH) used to search the MEDLINE database included: a) prostati c neoplasms; b) prostatic neoplasms/radiotherapy; c) prostatic neoplasms/an drogen deprivation; d) hormone therapy; e) English; and f) 1980 to 1998. Results: A total of 14 retrospective studies were identified that compared some form of androgen deprivation given in combination with RT. Most studie s showed significant improvements in various measures of local/regional con trol and disease-free survival (DFS). Three of four studies that analyzed B C rates showed significant improvements in this endpoint but conflicting re sults were obtained for overall survival (OS). No study showed an improveme nt in CSS. Six prospective randomized trials were identified that directly compared RT with or without androgen deprivation. Again, all six studies sh owed improvements in some measure of local/regional control or DFS but only two studies showed an improvement in OS. One study reported a statisticall y significant improvement in CSS and another study showed an improvement in the rate of negative biopsies with combined treatment. Conclusions: When all available literature on androgen withdrawal given in combination with RT for the definitive treatment of localized prostate canc er was reviewed, no definite conclusions could be reached on the impact of this treatment approach on OS and CSS. However, local/regional control, DFS , and PC were almost uniformly improved with the use of androgen withdrawal suggesting that these impressive early results may translate into improved cure rates. Data from recently initiated and completed randomized trials w ill be needed, however, to define the impact of this approach on cancer spe cific mortality and the patients most suitable for it's use. (C) 1999 Elsev ier Science Inc.