Again, prostate cancer confusion continues to reign. A recent study reported at the ASTRO (American Society for Radiation Oncology) conference claims that the addition of androgen deprivation therapy (ADT) in men with clinically localized prostate cancer was not associated with increased cardiovascular mortality.
According to Jason A. Efstathiou, MD, Ph.D.l, of the Massachusetts General Hospital in Boston, and colleagues. in a multivariate analysis of data from a 1,979 man study men receiving hormonal therapy with radiation had no increase in death from cardiac causes compared with men treated with radiation alone (HR 0.93, 95% CI 0.69 to 1.26, P=0.64. All subjects were over the age of 70 years.
This study was published as an abstract and presented at the ASTRO conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
“Most, though not all, population-based analyses have suggested that the gonadotropin-releasing hormone agonists are associated with a risk of coronary heart disease, myocardial infarction, and diabetes in men with prostate cancer,” said Efstathiou. The FDA asked manufacturers of these drugs to add safety labeling to that effect, significant controversy remains surrounding the potential effects of the GnRH agonists on cardiovascular death, he explained.
At baseline, the men randomized to radiation plus androgen deprivation therapy was very similar to those receiving radiation alone in terms of age, disease characteristics, and traditional cardiovascular risk factors.
The cumulative 10-year incidence of cardiovascular death was 9.8% in the combined treatment group and 10.7% in the radiation arm, which was not a statistically significant difference.
Univariate analysis determined that androgen deprivation did improve overall and disease-specific survival but did not worsen cardiovascular mortality.
“Although the GnRH agonists are associated with diabetes, their metabolic changes have mixed effects on predicted cardiovascular risk.
More work is needed to clarify the adverse effects of androgen deprivation therapy, including the increased rates of diabetes, fracture, and anemia, and to help establish risks and benefits.
Primary source: American Society for Radiation Oncology
Efstathiou E, et al “Cardiovascular mortality following short-term androgen deprivation in clinically localized prostate cancer: an analysis of RTOG 94-08” ASTRO 2011; Abstract 82.
Joel T Nowak, M.A., M.S.W.