WASHINGTON (Reuters) - Cholesterol-lowering drugs called statins modestly reduce levels of a protein in a man’s blood that doctors often use to screen for prostate cancer, researchers said on Tuesday.
But it remains uncertain whether men who take statins have a lower risk for developing prostate cancer or whether the drugs may make it harder to detect prostate tumors with a common screening blood test, the researchers said.
Prostate specific antigen, or PSA, levels dropped by about 4 percent in 1,214 men at a veterans’ medical center in North Carolina after they began taking statins, the researchers wrote in the Journal of the National Cancer Institute.
The biggest PSA declines were seen in men who took higher statin doses, those who had the biggest drop in cholesterol levels, and those who had the highest PSA levels to begin with, the researchers said.
A common screening test for prostate cancer measures levels of PSA, a protein produced by the prostate gland. Elevated PSA levels may indicate cancer or other prostate conditions.
If a man has a certain level of PSA, doctors might order a biopsy to confirm that there is cancer in prostate tissue.
Dr. Stephen Freedland of Duke University School of Medicine and the Durham Veterans Affairs Medical Center in North Carolina, who led the study, said he believes statins may cut a man’s risk of developing aggressive, advanced prostate cancer.
But it also is possible statins may make it tougher to screen for prostate cancer by obscuring evidence of disease.
“It’s obviously the unanswered question: is this a good thing that we’ve lowered their PSAs and therefore their chance of prostate cancer is lower? ... Or are we just masking the cancer and making it harder to detect. I wish I had that answer,” Freedland said in a telephone interview.
“In a good proportion of these men, the PSA levels declined sufficiently to a point where physicians might not recommend a biopsy, so it’s really important that we understand what’s at work here, so we can be sure we’re not missing cancers because of deceptively low PSA levels,” Dr. Robert Hamilton of the University of Toronto, another of the researchers, said in a statement.
Statins, the world’s top-selling drugs, cut heart attack and stroke risk. Studies have suggested a number of other benefits including protecting against Alzheimer’s disease, dying from pneumonia or developing dangerous blood clots.
Research has been less clear about statins and cancer.
Statins include atorvastatin, made by Pfizer Inc under the brand name Lipitor; pravastatin or Pravachol, made by Bristol-Myers Squibb; fluvastatin, made by Novartis AG under the brand name Lescol; and several others.
Separately, findings released on Monday from a study funded by the U.S. National Institutes of Health showed that taking selenium and vitamin E supplements, either alone or in combination, did not reduce the risk of prostate cancer.
Prostate cancer is the second most commonly diagnosed form of cancer in men worldwide, with about 780,000 men diagnosed per year, and the sixth mostly deadly form, with about 250,000 deaths per year, the American Cancer Society said.
Editing by Julie Steenhuysen and Eric Walsh