The study, presented at the 96th Annual Meeting of the American Association for Cancer Research, found that men who used these medications had half the risk of advanced prostate cancer and a third of the risk of metastatic or fatal prostate cancer, compared to men who did not use cholesterol-lowering drugs. Risk of advanced prostate cancer fell with increasing duration of use of the drugs. The study did not find that use of cholesterol-lowering drugs had any influence on prostate cancer that is confined within the organ.
But while the researchers, from Johns Hopkins University, the National Cancer Institute and Harvard University, say that the magnitude of the inverse association between use of cholesterol-lowering drugs and advanced prostate cancer is impressive, they stress that confirmatory studies are needed.
"This is a very interesting and promising lead on a class of drugs that may be offering benefits that were not anticipated, but we need to replicate the findings in other large prospective studies as well as figure out the mechanisms at work," says lead investigator Elizabeth Platz, Sc.D., M.P.H., an assistant professor at the Johns Hopkins Bloomberg School of Public Health.
"If the conclusions continue to hold up over time, there is great translational potential for preventing invasive and metastatic prostate cancer," she says. The researchers believe most of the protective effect they observed comes from statins, rather than other types of cholesterol-lowering drugs, because by 2000 more than 90 percent of the men who reported that they were using cholesterol-lowering drugs said that they were using statins, in particular. The researchers also say they don't know whether the apparent benefit of statins is due to their cholesterol-lowering effect or their other properties, such as their anti-inflammatory activity or their effects on post-translational modification of proteins.
The work was conducted in the Health Professionals Follow-up Study, an ongoing, large prospective cohort study that began at the Harvard School of Public Health in 1986. The few other studies that have looked at use of statins and development of prostate cancer have shown mixed results.
This study is unique, Platz says, because of its size, that the use of the drugs was determined before the diagnosis of prostate cancer, and because it examined associations based on stage of the disease. All of the 34,438 participants were free of a prostate cancer diagnosis in 1990, but by 2000, 2,074 men were diagnosed with prostate cancer. Of these, 283 were advanced, and within this subgroup, 206 were metastatic or fatal.
"We are excited by these initial findings, which may motivate more basic, clinical, and epidemiologic research into what appears to be a very promising area for prostate cancer," Platz says.
Founded in 1907, the American Association for Cancer Research is a professional society of more than 24,000 laboratory, translational, and clinical scientists engaged in all areas of cancer research in the United States and in more than 60 other countries. AACR's mission is to accelerate the prevention and cure of cancer through research, education, communication, and advocacy. Its principal activities include the publication of five major peer-reviewed scientific journals: Cancer Research; Clinical Cancer Research; Molecular Cancer Therapeutics; Molecular Cancer Research; and Cancer Epidemiology, Biomarkers & Prevention. AACR's Annual Meetings attract more than 15,000 participants who share new and significant discoveries in the cancer field. Specialty meetings, held throughout the year, focus on the latest developments in all areas of cancer research.