Studies have suggested that finasteride—a drug commonly prescribed to treat enlarged prostates—may also help prevent bladder cancer. Those studies, however, did not examine this effect in African American or Hispanic patients. In research published online on February 16 in the Journal of Urology, Denzel Zhu and Alexander Sankin, M.D., and colleagues showed for the first time that finasteride’s protection against bladder cancer varies by race and ethnicity.

The investigators followed more than 42,000 patients with enlarged prostates at Montefiore Medical Center; nearly 6,000 of them were prescribed finasteride. Among Caucasian and Hispanic patients, taking finasteride was associated with a 36 percent reduced risk of developing bladder cancer compared with men who were not prescribed finasteride. However, no reduction in bladder cancer risk was observed in African American patients taking finasteride.

The results add to evidence that finasteride helps protect against bladder cancer. They also emphasize the need for diverse, multiethnic patient cohorts, since drug effects that benefit some racial/ethnic groups but may not help others. Mr. Zhu is a medical student and research fellow at Einstein. Dr. Sankin is an associate professor of urology at Einstein and Montefiore.