Prostate cancer is the second most com cause of cancer death among men.

Currently, 5-ARIs are used to treat certain noncancerous conditions, including male-pattern baldness and benign prostatic hyperplasia. These drugs lower the level of the hormone dihydrotestosterone, which can contribute to the growth of prostate cancer. The American Cancer Society estimates that 186,320 American men were diagnosed with the disease last year. The recommendation is based on evidence gathered from 15 clinical trials, including the large Prostate Cancer Prevention Trial (PCPT) of over 18,000 men aged 55 and older.

Kramer, MD, MPH, associate director for disease prevention at the National Institutes of Health and co-chair of the guidelines panel. Another 5-ARI, called Avodart, is also being tested as a prostate cancer preventive.

Key Recommendations The key recommendations in the guideline include. While the guidelines call for discussing the whole class of drugs with your doctor, only Proscar has been proven to reduce cancer risk to date, notes says Maxim S. Proscar is a type of drug known as a 5-alpha reductase inhibitor (5-ARI). In that study, men who took a Proscar pill daily for one to seven years were about 25% less likely to develop prostate cancer than men who took a placebo.

Men with a prostate-specific antigen (PSA) level of 3.0 or below who are screened regularly, or who plan to.