Androgen Deprivation Therapy For Localized Prostate Cancer Not Associated With Improved Survival

Prostate cancer is the most common nonskin cancer and the second most common cause of cancer death among men. "For the majority of men with incident prostate cancer (approximately 85 percent), disease is diagnosed at localized (T1-T2) stages, and standard treatment options include surgery, radiation, or conservative management (i.e., deferral of treatment until necessitated by disease signs or symptoms). Although not standard or sanctioned by major groups or guidelines, an increasing number of clinicians and patients have turned to primary androgen deprivation therapy (PADT) as an alternative to surgery, radiation, or conservative management, especially among older men," the authors write. In a 1999-2001 survey, PADT had become the second most common treatment approach, after surgery, for localized prostate cancer, despite a lack of data regarding PADT's efficacy.

Grace L. Lu-Yao, M.P.H., Ph.D., of the Cancer Institute of New Jersey, UMDNJ-Robert Wood Johnson Medical School, Piscataway, N.J., and colleagues assessed the association between PADT and disease-specific survival and overall survival in 19,271 men with T1-T2 (localized) prostate cancer (diagnosed in 1992 -- 2002). The patients, age 66 years or older, did not receive definitive local therapy (i.e., such as prostatectomy) for prostate cancer. Among the patients, 7,867 (41 percent) received PADT, and 11,404 were treated with conservative management, not including PADT. During the follow-up period (through December 2006 for all-cause mortality and through December 2004 for prostate cancer--specific mortality) there were 1,560 prostate cancer deaths and 11,045 deaths from all causes.

The researchers found that use of PADT for localized prostate cancer was associated with lower 10-year prostate cancer--specific survival (80.1 percent vs. 82.6 percent) and no increase in 10-year overall survival compared with conservative management. However, in a prespecified subset analysis, PADT use in men with poorly differentiated cancer was associated with improved 10-year prostate cancer--specific survival (59.8 percent vs. 54.3 percent) but not overall survival (17.3 percent vs. 15.3 percent).

"The significant adverse effects and costs associated with PADT, along with our finding of a lack of overall survival benefit, suggest that clinicians should carefully consider the rationale for initiating PADT in elderly patients with T1-T2 prostate cancer," the authors conclude.