Propecia, a drug widely used by men for hair loss, artificially lowers prostate cancer screening test results, a new study finds. Screening for prostate cancer involves testing blood for prostate specific antigen levels, or PSA. Higher-than-normal levels of the PSA protein suggests cancer in the prostate. Past research showed that Proscar, a drug used to treat enlarged prostate glands, “falsely” lowers PSA levels, perhaps allowing a tumor to go undetected until it is more advanced and therefore more dangerous. Propecia has the same active ingredient as Proscar but is taken at a lower dose. Dr. Anthony D’Amico at Brigham and Women’s Hospital and a colleague recently followed 355 men between the ages of 40 and 60, 285 of whom were taking Propecia. They tested participants’ PSA levels every 12 weeks over 48 weeks and found that in the 40-49 age group, PSA levels were 40 percent lower in men taking Propecia than those not on the drug. In the 50-60 age group, levels were 50 percent lower in drug users.
BOTTOM LINE: Men getting screened for prostate cancer should tell their doctors if they are using Propecia for hair loss.
CAUTIONS: The study lasted one year; longer studies are required to see long-term effects of Propecia on blood PSA levels.
WHAT’S NEXT: The authors want to see if men taking Propecia are more likely to be diagnosed with late-stage prostate cancer, suggesting cancer may have been overlooked earlier.
WHERE TO FIND IT: Lancet Oncology Online, Dec. 5
SENA DESAI GOPAL