Two new studies address the advantages of adjuvant long-term androgen deprivation therapy (ADT) for men with locally advanced prostate cancer, and how it is currently utilized by clinicians. In the first study, 10-year data from the European Organisation for the Research and Treatment of Cancer (EORTC) 22863 trial confirm the clinical benefit of sustained ADT after radiotherapy (RT). The second report reassuringly reveals that the recent fall in ADT usage in the USA hasn't affected the patients that need it most.

The long-term results of EORTC 22863 are reported in the November issue of Lancet Oncology. After a median follow-up of 9.1 years, the combination of RT and 3 years of androgen suppression using a luteinizing hormone-releasing hormone (LHRH) agonist continues to confer better survival than RT alone, without a related increase in cardiovascular mortality.

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Over the course of this trial, which was initiated in 1987, adjuvant ADT has become standard treatment for men with prostate cancer at high risk of metastasis. However, concerns arose in the 1990s that ADT was being overused, owing to Medicare policy making the purchase of LHRH agonists profitable to clinicians. In response, the Medicare Modernization Act was implemented in 2003. This imposed a steep cut in payout over the next 2 years, resulting in a 14% decline in ADT usage in the USA. Vahakn Shahinian and colleagues set out to determine which patients were affected by this cut, using data from 54,925 men in the Surveillance, Epidemiology, and End Results Medicare database.

Encouragingly, they found no change in the use of ADT after RT for men with locally advanced disease (odds ratio 1.01; 95% CI 0.86–1.19), but the use of primary ADT in men with low-grade or moderate-grade tumors—for which there is no evidence of benefit—dropped dramatically (from 38.7% in 2003 to 25.7% in 2005).

“In other words, physicians continue to use therapies that are clearly beneficial even when substantial financial motivation is taken away, but cut back on use for which benefits are uncertain,” says Shahinian. “These are potentially important lessons for health care reform policy that may be broadly applicable, well beyond the prostate cancer field.”