We've talked a lot about the possibility of heart damage for breast cancer patients taking Herceptin or patients receiving an anthracycline, but new research shows there's also a chance that prostate cancer patients taking hormonal treatment may develop heart problems, although some types of therapy appear to be less risky than others.The study, presented in Berlin at a joint meeting of the European Cancer Organisation and the European Society for Medical Oncology, looked at more than 30,000 Swedish men who received hormonal therapy for about three years to treat advanced prostate cancer."If we have observed a causative effect, then for all hormone therapies put together, we estimate that compared with what's normal in the general population, about 10 extra ischaemic heart disease events a year will appear for every 1,000 prostate cancer patients treated with such drugs," the study's leader, Mieke Van Hemelrijck, a cancer epidemiologist at King's College in London, said in a statement. "However, not all types of therapy were associated with the risk of heart problems to the same degree. We found that drugs which block testosterone from binding to the prostate cells were associated with the least heart risk, while those that reduce the production of testosterone were associated with a higher risk. This may have implications for treatment choice."Researchers believe testosterone has some protective effect on the heart, so interfering with that could be harmful--a thinking supported by the data. The increased heart failure risk for anti-androgens (for example, Casodex and Nilandron) was 5 percent, compared with 34 percent for gonadotropin-releasing hormone agonists (for example, Zoladex and Lupron); the increased risk for ischaemic heart disease (reduced blood supply to the heart) was 13 percent in the anti-androgen group, compared with 30 percent in the gonadotropin-releasing hormone agonist therapy group. For men who had their testicles removed, the heart risk was close to that seen with gonadotropin-releasing hormone agonist therapy.Although the risk is small and may ultimately be outweighed by the benefits of hormonal therapy to treat prostate cancer, experts say men, particularly those at risk for heart disease, should talk with their doctor. Heart function may need to be monitored during treatment, and some patients may require referral to a cardiologist before starting treatment.