Does Aspirin Prevent Colon Cancer? Recent Studies Looking at How Common Medicines Reduce Risk

LONG ISLAND, NY – Almost 50,000 people will die this year in the US from colon cancer, with your personal lifetime risk of getting colon cancer estimated around 5%. This means that one out of twenty people will develop this disease in their lifetime. The good news about colon cancer is that it is somewhat preventable. Certain diet and lifestyle choices can reduce the risk of getting colon cancer, and it should go without saying that smoking increases the risk of pretty much all cancers. Having a screening colonoscopy (starting at age 50 for most people) is currently thought to be the best way to prevent colorectal cancer, since this test can remove the small polyps that may eventually grow into cancer.

More recently, there have been several studies looking at how common medicines like aspirin and other anti-inflammatory drugs (“NSAIDs” such as ibuprofen, naproxen, etc.) can reduce your risk of developing colon cancer. Since chronic inflammation is thought to increase the risk of developing many cancers, drugs like aspirin and ibuprofen are believed to reduce the risk of developing colorectal cancer by acting as anti-inflammatory substances. In fact, a large high-quality study published earlier this year demonstrated a 27% reduction in the risk of developing colorectal cancer for people taking low-dose aspirin (a.k.a. “baby” aspirin). The benefit was seen mainly in people that took aspirin daily for over 5 years. Also, drugs like ibuprofen and other NSAIDs had an even better protective effect.

So should everyone take aspirin daily to prevent colon cancer? I think the answer is no. For one thing, we have to look at the risks associated with aspirin and other NSAIDs, namely stomach bleeding, ulcers, kidney problems, and more rarely heart attack (with non-aspirin NSAIDs) or stroke. Also, the data on these drugs in preventing colon cancer is good, but not great. The studies all have some flaws, and factoring some of the risks of chronic aspirin or NSAID use into the picture it seems clear that this strategy is not for the average patient.

On the other hand, a high-quality screening colonoscopy, when done by an experienced gastroenterologist, has been shown to decrease the risk of developing colon cancer by about 70%. Virtually all colon cancers start off as small polyps, which ideally can be found with colonoscopy and removed at the same time. It is a 20 minute procedure that is painless and only needs to be repeated once every several years (depending on your personal risk factors). It is recommended that both men and women start getting colonoscopies at age 50, earlier if you have a family history of colorectal cancer, or if you have concerning symptoms.

On a somewhat related note, it is perfectly safe to keep taking a baby aspirin before, during, and after the day of your colonoscopy. And if you are taking aspirin anyway for another reason (for example, a cardiac stent), rejoice in the fact that you are probably reducing your risk of colon cancer as well. Just don’t use this as an excuse to avoid getting a colonoscopy.

Dr. Frederick Gandolfo is a board certified gastroenterologist practicing in Lake Success, NY, and affiliated with Winthrop-University Hospital. He attended SUNY Stony Brook School of Medicine, and completed training in internal medicine and gastroenterology at NYU. He is a general gastroenterologist with special expertise in colonoscopy, inflammatory bowel disease, and colon cancer prevention.

He writes regularly about medical topics on his website retroflexions.com. Follow Dr. Gandolfo on Twitter and Facebook, or contact him at Gastrointestinal Associates of Long Island.