Statins May Help Prevent Colon Cancer
Promising results for cholesterol-lowering drugs in observational study
WEDNESDAY, May 25, 2005 (HealthDayNews) -- Patients taking cholesterol-lowering statin drugs may also be protecting themselves from colorectal cancer, researchers report.
The finding comes on the heels of other studies announced last week that suggested statins may also help prevent pancreatic, lung, prostate and breast malignancies.
In this latest study, researchers found that regular use of statins cut the odds of developing colorectal cancer by almost 50 percent.
"Statins are very powerful drugs," said co-researcher Dr. Stephen B. Gruber, an associate professor of internal medicine, epidemiology and human genetics at the University of Michigan.
"These powerful drugs have more than one effect. Experimental data clearly show that they target pathways relevant to cancer," he added.
In the study, Gruber's team compared statin use by 1,953 patients in Israel who had been diagnosed with colorectal cancer between 1998 and 2004 with statin use by 2,015 others used as a control group. Simvastatin (Zocor) and pravastatin (Pravachol) were the two most commonly used statins within the study group.
"We observed a strong protective effect of statins associated with the risk of developing colorectal cancer," Gruber said. "Statins appear to be protective for the development of colorectal cancer."
The study conclusion found a 47 percent "relative reduction in the risk of colorectal cancer after adjustment for other known risk factors."
But Gruber added that further study was needed because the absolute risk reduction was probably low.
The report appears in the May 26 issue of the New England Journal of Medicine.
"These are very promising drugs for future studies for the prevention of the third most common cancer in the United States," Gruber said.
However, the Michigan researcher cautioned that this is only an observation in a selected population. To prove whether or not statins really help prevent colorectal cancer, researchers need to conduct a randomized clinical trial that pits these medicines, which also include Crestor and Lipitor, against a placebo.
Until that time, "this observational study should not change the way these drugs are currently used," he stressed.
Gruber believes the findings should spur investigation into whether statins have health benefits outside of their effect on cholesterol. "This is a unique window of opportunity to study these drugs," Gruber said.
One expert believes statins may indeed hold great promise in the fight against cancer.
"One of the compelling features of statins is they may have potential activity against multiple diseases," said Dr. Jaye L. Viner, chief of the Gastrointestinal and Other Cancers Research Group in the division of Cancer Prevention at the National Cancer Institute (NCI).
Viner, who is also the co-author of an accompanying editorial, said the results must be viewed with caution, however, because they have not yet been proven in clinical trials. "The data are suggestive, but they are not absolute," she added.
In fact, the NCI is currently sponsoring a study testing a statin against colorectal cancer, Viner said. That trial, set to begin at the end of this year, "should enhance our appreciation for what this drug might do in the context of colorectal [cancer]," she said.
In keeping with the advice of the other experts, Viner stressed that until there is hard data that statins do help prevent malignancies, patients should not take them solely as a cancer-preventive agent.
"It would be premature to recommend statins as chemopreventive agents against colorectal or other cancers," Viner said. "Given the state of the science, it is appropriate to test these in a clinical trial and find the answers that are going to potentially prove beneficial to the public."
Another expert agrees the findings are interesting, but need to be proved in clinical trials.
"This study adds to the body of other literature that has been developing that suggests that statins may play some role in prevention of colorectal cancer and a variety of other cancers," said Dr. Durado Brooks, director of colorectal and prostate cancer at the American Cancer Society. "Now that we have all this suggestive data, we need much more challenging randomized, controlled trials."
Cancer prevention may not yet be a primary reason to take statins, Brooks added, but patients already on the drug may be picking up this additional benefit.
"If your doctor prescribes a statin because of cholesterol problems, this is at least one further inducement to make sure you are compliant with your medications," he said.
The American Cancer Society can tell you more about colorectal cancer.