Prostate cancer has an unpredictable natural history if left untreated, particularly if the neoplasm is discovered when it is apparently organ confined. To our knowledge we report the first case of organ confined adenocarcinoma of the prostate in a cardiac transplant recipient. The therapeutic decision is complicated by the uncertainty of the impact of continued immunosuppression on tumor growth. Although the effect of immunosuppression on the growth of prostate cancer is unknown, our patient was treated within the accepted guidelines for similarly affected nonimmunosuppressed individuals. Improvements in long-term survival rates of patients undergoing cardiac transplantation warranted radical surgical ablation as treatment for this man with clinically organ confined prostate cancer.