Incidence of prostate cancer in hypogonadal men receiving testosterone therapy: observations from 5-year median followup of 3 registries.

PURPOSE Although there is no evidence that testosterone therapy increases the risk of prostate cancer, there is a paucity of long-term data. We determined whether the incidence of prostate cancer is increased in hypogonadal men receiving long-term testosterone therapy. MATERIALS AND METHODS In 3 parallel, prospective, ongoing, cumulative registry studies 1,023 hypogonadal men received testosterone therapy. Two study cohorts were treated by urologists (since 2004) and 1 was treated at an academic andrology center (since 1996). Patients were treated when total testosterone was 12.1 nmol/l or less (350 ng/dl) and symptoms of hypogonadism were present. Maximum followup was 17 years (1996 to 2013) and median followup was 5 years. Mean baseline patient age in the urological settings was 58 years and in the andrology setting it was 41 years. Patients received testosterone undecanoate injections in 12-week intervals. Pretreatment examination of the prostate and monitoring during treatment were performed. Prostate biopsies were performed according to EAU guidelines. RESULTS Numbers of positive and negative biopsies were assessed. The incidence of prostate cancer and post-prostatectomy outcomes was studied. A total of 11 patients were diagnosed with prostate cancer in the 2 urology settings at proportions of 2.3% and 1.5%, respectively. The incidence per 10,000 patient-years was 54.4 and 30.7, respectively. No prostate cancer was reported by the andrology center. Limitations are inherent in the registry design without a control group. CONCLUSIONS Testosterone therapy in hypogonadal men does not increase the risk of prostate cancer. If guidelines for testosterone therapy are properly applied, testosterone treatment is safe in hypogonadal men.