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5-ARIs Do Not Lower Bladder Cancer Risk

In This Article

  • 5-alpha reductase inhibitors (5-ARIs), commonly used to reduce the size of the prostate, have been suggested as a treatment for bladder cancer
  • A recent study of nearly 40,000 men found that the use of 5-ARIs did not have a protective effect against bladder cancer
  • Future research is needed to identify an alternate strategy for chemoprevention of bladder cancer

The use of 5-alpha reductase inhibitors (5-ARIs) does not have a protective effect against bladder cancer, according to a large prospective cohort study presented at the American Urological Association 2020 Virtual Experience. The study, led by Keyan Salari, MD, PhD, urologic surgeon with the Massachusetts General Hospital Department of Urology and urologic oncologist at the Mass General Cancer Center, examined a cohort of nearly 40,000 men from the Health Professionals Follow-up Study in the U.S. and found no difference between prediagnostic 5-ARI use and development or death from bladder cancer. Over a 16-year follow-up period, 943 men were diagnosed with bladder cancer and 159 died due to bladder cancer.

Controlling for certain risk factors, including age, smoking and alcohol use, the investigators noted a non-significant 25% increased risk and a 54% increase in death associated with 5-ARI use in contrast with other retrospective studies. The duration of 5-ARI use was also not associated with risk or death due to bladder cancer. The researchers note that these findings could be in part due to the increased likelihood of urologic evaluation while on the medications.

5-ARIs are commonly prescribed to reduce the size of the prostate, but have also been suggested as a potential treatment for bladder cancer development and recurrence in recent retrospective studies. Dr. Salari says that a strategy for chemoprevention of bladder cancer would have tremendous clinical implications for how this disease is treated and possibly prevented altogether. However, 5-ARIs show no evidence of being effective chemopreventative agents against bladder cancer.

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