BPH drug cleared of causing aggressive tumors

Finasteride, a drug prescribed to ease the symptoms of benign prostatic hyperplasia (BPH), has already been shown to help prevent prostate cancer. In September, two groups of researchers reported that it doesn’t cause high-grade tumors and, in fact, that it might aid in the detection of aggressive cancers. Their studies show that the drug seems to keep the prostate gland small, making it more likely that physicians will find dangerous tumors inside the gland or on its surface when doing biopsies.

When finasteride was first tested for cancer prevention, researchers noticed that men who developed cancer were slightly more likely to harbor aggressive tumors. Although the drug lowered the overall risk of cancer by 25%, physicians and scientists worried that it might somehow be making cancer worse if it were already present. The two new studies, however, offer reassurance. They suggest that early diagnosis (due to relatively smaller prostates), as well as the drug’s ability to inhibit some low-grade cancers, contributed to the “increase” in high-grade cancers, not finasteride itself.

Sources: Lucia MD, Epstein JI, Goodman PD, et al. Finasteride and High-Grade Prostate Cancer in the Prostate Cancer Prevention Trial. Journal of the National Cancer Institute 2007 (E-publication). PMID: 17848673.

Cohen YC, Liu KS, Heyden NL, et al. Detection Bias Due to the Effect of Finasteride on Prostate Volume: A Modeling Approach for Analysis of the Prostate Cancer Prevention Trial. Journal of the National Cancer Institute 2007 (E-publication). PMID: 17848668.

Originally published April 2009; last reviewed February 24, 2011.