Testosterone replacement therapy in men with prostate cancer after proton therapy.

Abstract

208 Background: Testosterone replacement therapy (TRT) in patients previously treated for prostate cancer is controversial. We analyzed biochemical relapse and sexual function in patients treated for prostate cancer with proton therapy (PT) at our institution who were later treated with TRT for hypogonadism. Methods: We reviewed the medical records of 27 patients with biopsy-proven, localized prostate cancer treated with definitive proton therapy (PT) at our institution between 2006 and 2012. Each patient had hypogondal symptoms and low-serum testosterone and received testosterone replacement after PT. Biochemical failure was defined by the Phoenix definition. Sexual function was reported using patient-reported data from the Expanded Prostate Cancer Index Composite (EPIC) questionnaire. Rates of sexual potency were also reported. Results: Twenty-three patients were included in the present analysis. The median follow-up duration was 38 months after PT and 14 months after initiation of TRT. After one to six months on TRT, the median serum testosterone level in this patient cohort increased from 238 to 497. No patient experienced a biochemical failure. The median prostate-specific antigen (PSA) did not significantly rise during the follow-up period. EPIC sexual summary, sexual function, and sexual bother scores all increased after initiation of TRT. The median sexual bother scores increased from 43.8 before TRT to 59.4 after 7 or more months of TRT. The median sexual summary scores improved from 50 to 61.8 and the median sexual function scores improved from 41.7 to 53 over the same time. Sexual potency also increased after TRT initiation from 50% to 68%, 7 or more months after TRT. Conclusions: For patients diagnosed with hypogonadism who were previously treated for prostate cancer, cautious use of testosterone replacement therapy does not appear to increase the risk of biochemical failure or increase PSA. Sexual function may improve to approximate pre-radiation levels in some cases. A prospective trial with long-term follow up is required to better support our findings.