Weighing Risk of Cardiovascular Mortality Against Potential Benefit of Hormonal Therapy in Intermediate-Risk Prostate Cancer

Background: The purpose of this study is to determine the optimal strategy for men with newly diagnosed intermediate-risk prostate cancer by age and cardiac risk. Methods: A Markov model was calibrated to the EORTC 22991 trial, which randomly assigned men with intermediate-risk prostate cancer to radiation therapy (RT) with or without six months of hormonal therapy (HT). We compared quality-adjusted life-years (QALYs) in men age 50, 60, and 70 years by age decile and cardiac risk group. Competing risks of cardiovascular mortality were estimated from the published literature. Sensitivity analyses were used to assess the impact of varying model assumptions. Results: HT was associated with a net decrease of 0.3 to 0.4 QALYs in men with a history of myocardial infarction. However, for all other men, HT improved QALYs (range = 0.4-2.6 QALYs). Younger men with fewer cardiac risk factors experienced the largest benefit from HT. In sensitivity analyses, the model was only found to be sensitive to the probability of biochemical failure. Men at low risk for biochemical failure (≤8.7% at five years) did not benefit from HT. Further, the benefits of HT did not begin to manifest until after 7.3 years of follow-up. Conclusions: The optimal choice of therapy depends upon age, cardiac risk, and disease recurrence risk. Young men with intermediate-risk prostate cancer with no cardiac risk factors benefit most from HT. Men with a history of myocardial infarction who are at very low risk for biochemical failure may be negatively impacted by the addition of HT.