Intermittent ADT May Offer Survival Edge in Advanced Prostate Cancer
ATLANTA—Intermittent androgen deprivation (IAD) therapy is associated with improved all-cause and prostate cancer (PCa)-specific mortality among elderly patients with advanced PCa, according to data presented at the American Urological Association 2012 annual meeting.
Benjamin A. Spencer, MD, of Columbia University Medical Center in New York, and colleagues studied 3,073 patients with stage IV PCa treated with androgen deprivation therapy. Of these, 25% received IAD and 75% received continuous androgen deprivation (CAD).
Younger age, more recent PCa diagnosis, and urban residence predicted IAD receipt. Compared with patients aged 65-69 years, those aged 75-79, 80-84, and 85 years and older were 36%, 31%, and 54% less likely to receive IAD, respectively.
In multivariate analysis, patients who received IAD had a 16% and 18% decreased risk of all-cause mortality and PCa-related mortality, respectively, compared with CAD recipients.
The researchers defined IAD as the discontinuation of ADT for at least six months and within two years of starting it.
“Androgen deprivation therapy is a mainstay of therapy for metastatic prostate cancer,” Dr. Spencer said. “Androgen deprivation therapy has significant morbidities and therefore intermittent therapy has been proposed as an alternative regimen to try to minimize some of these morbidities.
IAD has the possible advantage of delaying development of castration-resistant disease, it is more convenient for patients and less expensive for the health care system, Dr. Spencer noted.
Although a number of trials have shown that IAD is not inferior to CAD, Dr. Spencer said, slightly longer follow up probably is necessary “to really definitively say that intermittent therapy can be considered a standard of care in this area.”