Statin Drugs May Cut Colon Cancer Risk
More Study Needed To Determine If Effect Is Real
June 7, 2004 (New Orleans) -- Colon and rectal cancers are the No. 2 cancer killers in the United States; now new research suggests a type of drugs that lowers cholesterol may cut the risk of developing these cancers.
Statins, marketed under names such as Crestor, Lescol, Lipitor, Mevacor, Pravachol, and Zocor, are a type of drug commonly prescribed to lower cholesterol, but cancer researchers suspect they may also inhibit the growth of cancer.
To test that theory, S.B. Gruber, MD, PhD, and colleagues from the University of Michigan along with scientists at CHS National Cancer Control Center in Haifa, Israel, looked at the use of statin drugs in 1,849 people with colorectal cancer and in 1,959 people without the disease. The study results were presented at the 40th Annual Meeting of the American Society of Clinical Oncology.
51% Colon Cancer Risk Reduction
Among the colon cancer patients, 6% had taken statins, while 11% of the healthy people had used the drugs, Gruber tells WebMD. That means that taking statin drugs was associated with a 51% reduction in risk of colon cancer.
However, many factors can alter the risk for colon cancer so Gruber and his colleagues factored in things like aspirin use, diet -- especially a diet high in fruits and vegetables, exercise, and family history.
When they added in those factors, "use of statins was still associated with a 46% reduction in risk."
Moreover, Gruber says the benefit is not just about lowering cholesterol because when he looked at other drugs used to lower cholesterol levels, "we found no benefit."
In Israel the most commonly used statins are Zocor and Pravachol and the benefit was the same with both drugs, which makes Gruber think that all statins are likely to offer the same benefit.
Statins for Prevention Not Yet Recommended
But he says it is too early to suggest taking statins as a means of preventing colorectal cancer.
Monica Morrow, MD, a professor of surgery at the Lynn Sage Comprehensive Breast Program at Northwestern University in Chicago tells WebMD she agrees with Gruber's caution about jumping to conclusions.
She pointed out that observational studies like this one that observe a particular drug's effect can often lead to wrong conclusions. The classic example, she says, washormone replacement therapy, which was given to many women as a way to reduce the risk of heart disease and stroke but when tested the hormone actually increased risk.
Yet, she says the statin finding is "enormously interesting. It fits with what we know from lab work." Morrow, who was not involved in the study, says studies in animals have suggested that statins can reduce risk of some cancers.
According to the American Cancer Society, about 147,000 new cases of colorectal cancer will be diagnosed this year and some 57,000 Americans will die from colorectal cancer in 2004.
SOURCES: 2004 American Society of Clinical Oncology Annual Meeting, Abstract 1: "HMG CoA reductase inhibitors and the risk of colorectal cancer,"presented June 7, 2004. Stephen Gruber MD, PhD. Monica Morrow, MD.