Low-dose aspirin can help protect against colorectal cancer, but talk to your doctor first.
Colorectal polyps are small, non-cancerous (benign) clumps of cells that grow in the rectum and colon. Over the course of 10–15 years, some of these polyps—usually the ones that are larger than a pea—may become cancerous. Fortunately, regular screening for colorectal cancer helps to identify and remove polyps, often before they progress to cancer.
It’s not known why some people get polyps, but some individuals are more prone to polyps than others. For instance, the older you get—especially after age 50—the more likely you are to have polyps. You’re also more likely to develop polyps if you’ve had them before (polyps tend to recur in most people), or if someone in your family has had polyps or cancer of the colon. Your behaviors also influence your risk of getting polyps: Eating a lot of fatty foods, smoking cigarettes, drinking alcohol, not exercising, and being overweight can all contribute to the formation of polyps.
Most polyps don’t cause any symptoms. You might not know you have polyps until your doctor finds them during a physical examination or colorectal cancer screening. However, some people may notice rectal bleeding, especially after a bowel movement, constipation or diarrhea that lasts longer than a week, or blood in their stool (the stool looks black or contains red streaks). In these cases, you should see your doctor for an evaluation. Polyps can be diagnosed by a digital rectal exam, barium enema, sigmoidoscopy, or colonoscopy.
Following a healthy diet, exercising, and not smoking may help prevent polyps. Furthermore, research indicates that regular strength aspirin (325 mg a day) may thwart the growth of polyps in people who have recovered from colorectal cancer. For people who haven’t had colorectal cancer, other research suggests that aspirin use is most effective as a protectant if you have a mutated form of a gene that helps break down aspirin. Based on this data, your doctor may recommend aspirin to reduce the risk of polyps if you are at high risk. Always consult your doctor before beginning regular aspirin therapy to determine if the practice will be more beneficial than harmful given your individual medical history. In some people, regular use of aspirin can cause serious side effects, such as bleeding in the digestive tract.
More about aspirin therapy to prevent polyps and colorectal cancer
A large study in women has confirmed the benefits of long-term aspirin or nonsteroidal anti-inflammatory drug (NSAID) use in reducing the risk of colorectal cancer. But it also confirmed that bleeding in the digestive tract is a possible side effect. In the 20-year trial of 83,000 women, which was reported in the Journal of the American Medical Association, those who regularly took two or more 325-mg aspirin tablets a week had a 23% lower risk of colorectal cancer than did non-aspirin users. Those who took 15 or more aspirin tablets a week received an even greater benefit—and had half the risk of non-users. However, these reductions in risk only became apparent after 10 years of consistent aspirin use.
Similar results were found with the regular use of non-aspirin NSAIDs such as ibuprofen (Advil, Motrin). Of concern was the significantly increased risk of digestive tract bleeding in women who used large doses of aspirin or NSAIDs (15 or more tablets a week). Using aspirin to prevent colorectal cancer requires a much higher dose than that needed to prevent cardiovascular disease and regular NSAID use may increase the risk of heart attack and stroke. Thus, more studies are needed to clarify the risk to benefit ratio of high-dose aspirin in preventing colorectal cancer. Other trials have found that regular aspirin use also protects against colorectal cancer in men.
The nonaspirin NSAID celecoxib (Celebrex) was approved by the U.S. Food and Drug Administration to reduce the risk of polyp formation in people with familial adenomatous polyposis (FAP). Celebrex is associated with lower rates of digestive track bleeding than other NSAIDS. However, it may increase the risk of heart attack or stroke. If you have FAP, ask your doctor if you are a candidate for Celebrex.
From Polyp to Cancer: Click here for a colon cancer polyp diagram which shows the progression of the disease.
For more Alerts and Special Reports, please visit the Colon Cancer Topic page.
