Weighing Results of Prostate Cancer Study

When a recent study involving a drug to prevent prostate cancer received mixed results -- the preventative drug finasteride (Propecia or Proscar) reduced the prevalence of the cancer by nearly 25 percent but also appeared to raise the incidence of more serious cancers -- researchers were unsure what to do next.

A new study may be helping them decide. According to investigators who followed up on the original study with an analysis of the benefits and risks of the drug in the entire population of men ages 55 and older -- those most at risk for prostate cancer -- the drug would still save nearly 263,000 person-years over 10 years, despite the increased risk in serious cancers.

The investigators also say the debate continues on whether the increased incidence of high-grade cancers seen in the initial study (about 5 percent of men taking a placebo were diagnosed with high grade cancers compared to about 12 percent taking finasteride) was really caused by the drug or not. But they believe their findings indicate the payoff outweighs any risk that might exist.

Authors write, “Even if finasteride is found to potentiate the growth of high-grade tumors, this analysis shows that the potential detrimental effects of an increased rate of cases with high-grade Gleason score would be substantially outweighed by a reduction in incidence.”

They also emphasize the benefits that would accrue to the 25 percent of men who would be spared a cancer diagnosis. “The reduction in cost and morbidity as well as the psychosocial benefits of not having a cancer diagnosis potentially are as great as the life-years saved by this preventive intervention.”