People who take aspirin on a regular basis are two and a half to three and a half times less likely to develop cancer of the bile duct than those who rarely or never take the pain reliever. Bile duct cancer, also called cholangiocarcinoma, is uncommon but hard to treat, so prevention would be beneficial.
People with Bile Duct Cancer:
The investigators examined patient records from the Mayo Clinic Hepatobiliary Neoplasia Registry, the Mayo Clinic Biobank and the Rochester Epidemiology Project. They compared the records of 2,395 patients with bile duct cancer to those of 4,769 cancer-free people.
Aspirin Made a Difference:
Aspirin use was protective against all of the various subtypes of bile duct cancer. The scientists believe that inflammation is the common denominator of these tumors and that aspirin’s anti-inflammatory activity is probably responsible for its protective effect.
Previous Studies Point the Same Direction:
Regular aspirin use has also been shown to reduce the risk of a number of other cancers, particularly those of the digestive tract. Earlier studies have found, for example, that people taking aspirin to prevent heart attacks and strokes were 15 percent less likely to die of cancer of the colon, esophagus or stomach (The Lancet, April 28, 2012). Researchers with the Cancer Prevention Study II Nutrition Cohort used the health records of 100,000 American adults over 10 years to determine that those who took aspirin daily had a 40 percent lower chance of developing any digestive tract cancer (Journal of the National Cancer Institute, online Aug. 10, 2012).
A case-control study from China revealed that women who took aspirin at least twice a week were almost 50 percent less likely to be diagnosed with lung cancer (Lung Cancer, Aug., 2012).
A recent study also shows that aspirin can help lower the likelihood of metastases once a cancer has been diagnosed.
Downsides of Aspirin:
Aspirin can cause bleeding, although this risk seems to fade with time. It is also notorious for causing gastrointestinal irritation and ulceration, so the balance of benefit to risk must be carefully considered in each individual case.
Hepatology, online March 3, 2016