Despite previous research demonstrating that the use of phosphodiesterase type 5 (PDE-5) inhibitors such as sildenafil, tadalafil, and vardenafil may reduce the risk for developing prostate cancer, a new study published in the Journal of Urology suggests that these agents do not prevent prostate cancer.1
“In vitro mouse studies have suggested that these drugs might have some anticancer activity, but the evidence in human subjects is mixed,” said lead investigator Stephen J. Freedland, MD, Division of Urology, Department of Surgery at the Samuel Oschin Comprehensive Cancer Institute at Cedars-Sinai in Los Angeles, California. “Given the routine use of PDE-5 inhibitors and the possibility that these agents may have anticancer activity, we wanted to test the association between their use and risk of developing prostate cancer.”
To do so, researchers assessed whether use of PDE-5 inhibitors impacted the overall prostate cancer risk and disease grade among the 6501 participants of the 4-year, multicenter, REDUCE trial, which evaluated the effect of daily dutasteride for the treatment of benign prostatic hyperplasia on the risk of prostate cancer in men.
Results showed that 5.6% of the 6501 patients used PDE-5 inhibitors at baseline. The investigators found that 19.5% of these men ultimately developed prostate cancer compared with 22.7% of the men who did not take PDE-5 inhibitors. This difference was not statistically significant.
The study further demonstrated no association between PDE-5 inhibitor use and low or high grade disease. There was, however, a nonsignificant link between PDE-5 inhibitor use and a reduced risk of prostate cancer among North American men.
“Future studies with longer follow-up and larger study populations are warranted to determine the association between PDE-5 inhibitors and prostate cancer,” said Juzar Jamnagerwalla, MD, urology resident at Cedars-Sinai, and first author.
1. Elsevier Health Sciences. No link found between erectile dysfunction drugs and risk of prostate cancer [news release]. EurekAlert! website. http://www.eurekalert.org/pub_releases/2016-08/ehs-nlf080116.php. Published August 1, 2016. Accessed August 2, 2016.