Dr. Peter Greenwald, the Director of Cancer Prevention at the National Cancer Institutes, visits The Early Show to explain the significance of the New England Journal of Medicine study.
He says the research found that prostate cancer is in part preventable. But, Greenwald emphasizes, the study does not answer all the questions about the cancer, and there is still more research needed to be done.
The study also found that men taking the drug who get the disease may get a more aggressive form of it. Greenwald says there is no explanation to the finding.
Researchers also say a small percentage of men may experience impotence, loss of sexual drive and problems urinating after using Propecia. But, Greenwald says, many of the elder men would be experiencing some of the side-effects due to age.
Greenwald says the Food and Drug Administration and their advisory group will have to look over the study's findings before declaring the drug usable for battling prostate cancer. Then, he says, it will be up to men and their doctors to weigh the risks of using Propecia.
The study did not examine men under 55 years old taking lower doses of the drug.
Prostate cancer is the second-deadliest cancer for men after lung cancer.