Androgen-deprivation therapy (ADT) is associated with shortened survival in African American men with favorable-risk prostate cancer, according to a new study. The results suggest ADT should be reserved for men with higher risk disease.
“African American (AA) men, in comparison with non-AA men, are more likely to have more comorbid illness and to present with or harbor occult high-grade prostate cancer,” wrote study authors led by Konstantin A. Kovtun, MD, of the Dana-Farber Cancer Institute in Boston. Those comorbidities could interact with ADT and shorten survival, but the higher-grade cancer presents a dilemma of who should receive the therapy.
The new study included 7,252 men (533 AA, 6,719 non-AA) with low-risk or favorable intermediate-risk prostate cancer treated with brachytherapy and either with neoadjuvant ADT (1,501 patients) or without ADT (5,751 patients) between 1997 and 2013. The median follow-up was 8.04 years; the results were published online ahead of print in Cancer.
AA men were significantly younger than non-AA men, were treated later, were more likely to be considered favorable intermediate-risk rather than low-risk, and were more likely to have a cardiometabolic comorbidity at baseline. The use of neoadjuvant ADT was similar between AA (20.45%) and non-AA men (20.72%).
In total, 869 men died during the follow-up period, 48 of whom (5.52%) died of prostate cancer. On a multivariate analysis, AA race was significantly associated with an increased risk of all-cause mortality (adjusted hazard ratio, 1.77 [95% CI, 1.06–2.94]; P = .028) and other-cause mortality (HR, 1.86 [95% CI, 1.08–3.19]; P = .024) specifically among men who received ADT.
In those who did not receive ADT, AA race was associated with higher mortality risks as well, but this did not reach statistical significance.
“The clinical significance of this observation is that it suggests that a short course of neoadjuvant ADT as a part of treatment for low- or intermediate-risk prostate cancer may have a deleterious impact on survival for AA men vs non-AA men,” the authors wrote. “Because ADT is not recommended as part of the management of low-risk or favorable intermediate-risk prostate cancer, these findings should raise awareness about the potential negative impact on survival for AA men.”
The authors did note that these results are retrospective and will require validation in a prospective study, and the biological basis for the effect is unclear. Still, they concluded that “the use of ADT in AA men should be reserved for treating higher risk prostate cancer.”