Study Finds Decrease in Prostate Cancer Risk with Baldness Drug

A new follow-up study indicates that taking a male pattern baldness treatment drug to shrink an enlarged prostate did not cause more aggressive tumors to be formed. Although finasteride, the generic drug in question, was originally discovered in a 2003 study to reduce the overall risk for prostate cancer by 30 percent, during the Prostate Cancer Prevention Trial (PCPT) of almost 19,000 men, a slightly higher percentage of those on finasteride developed high-grade cancer than those taking a placebo.

In part because of the troubling finding from the original studies, finasteride has never been approved by the FDA to prevent prostate cancer, and in 2011, the FDA added a warning to the label about the increased risk of being diagnosed with high-grade prostate cancer. The researchers at the Cancer Therapy and Research Center continued tracking the PCPT trial participants, up to 18 years since the initial enrollment in the study, including searches of the Social Security Death Index through late 2011. The long-term follow-up study, published in The New England Journal of Medicine, confirmed that finasteride had no impact on lifespan but further reduced the risk of prostate cancer by about one-third. The researchers concluded that the higher percentage of high-grade cancers in men were detected because finasteride, by shrinking the prostate, made the prostate-specific antigen (PSA) test work better. In turn, this made it easier for the high-grade tumors to be found in biopsy samples.

The researchers estimated that widespread use of finasteride could save about 70,000 men a year from the emotional and physical trauma of prostate cancer diagnosis and treatment. The researchers stressed that using finasteride would not prolong their lives or protect from aggressive cancer, but it would lower their risk for low-grade prostate cancer. As a result, that would mean fewer men would receive unnecessary screening and treatment for the low-grade prostate cancer.

Screening does more harm than good, according to the U.S. Preventive Services Task Force, an independent panel of doctors who advise the federal government, because although 240,000 new prostate cancers are diagnosed each year in the United States, only about 30,000 prove fatal. With PSA screening, many men are treated for cancers that grow too slowly to be life-threatening, and often suffer sexual and urinary problems as a result.