A just-published study has sparked renewed debate about whether men should use the hair-loss drug finasteride to prevent prostate cancer.
Finasteride, used to treat male pattern baldness, is now widely used to shrink enlarged prostates, The New York Times reports. A 2003 study of 18,000 men showed that the drug also lowered a man’s risk for prostate cancer by 30 percent. But the U.S. Food and Drug Administration (FDA) never approved finasteride to prevent prostate cancer, because of a troubling finding. While the drug clearly reduced the overall risk for prostate cancer, slightly more men who used the drug developed fast-growing tumors compared with men who took a placebo, according to the Times.
A follow-up study, published on Wednesday in the New England Journal of Medicine will likely rekindle the finasteride debate. Study results, based in part on Social Security death records, indicate that 14 to 17 years after the men first enrolled in the study, the survival rate was the same for men who used finasteride and those who took a placebo. The findings suggest not that the drug was causing the aggressive tumors, but rather, that by reducing the size of the prostate, the drug made it easier to find aggressive tumors, according to the Times.
The study’s authors estimate that widespread use of finasteride could save about 70,000 men a year from the trauma of prostate cancer diagnosis and treatment. While the drug will not prolong lives or protect from aggressive cancer, it will lower the risk for low-grade prostate cancer, resulting in fewer men receiving unnecessary treatment. Decisions about when and whether to treat low-grade prostate cancers are controversial, with some doctors arguing against rushing into treatments that can leave a man impotent or incontinent.
Lead author Dr. Ian Thompson, director of the cancer therapy and research center at the University of Texas Health Science Center in San Antonio, said that because large numbers of men with low-grade tumors receive unnecessary treatment, there is a benefit to preventing low-grade, nondeadly cancers.
Dr. Peter Scardino, head of the prostate cancer program at Memorial Sloan-Kettering Cancer Center in New York, said the findings could pave the way for more research into prostate cancer prevention and treatments for men with early-stage prostate cancer, the Times reports. “We have a biological mechanism that can prevent these low-grade cancers, so it leaves the door open for further study. I don’t think we’ve heard the end of this story,” he said.