in March 2007, the United States Preventive Services Task Force (USPSTF) gave aspirin and other NSAIDs a D recommendation as a prophylactic against colon cancer as they believed that the potential harm exceeded the proof of benefit available at that point in time.Therefore, back
Fast forward to August 2009 when a study published in JAMA of 1,279 men & women w/various stages of colon cancer followed for close to 12yrs demonstrated that those who took aspirin after diagnosis had lower colon cancer-specific and all-cause mortality.
Just over a year later in November 2010, a meta-analysis was published in the Lancet of 8,282 participants randomized to various doses of aspirin and compared to 5,751 randomized to placebo, all followed for an average of 6yrs. The authors concluded that no more than 75mg daily was necessary to reduce the incidence of, and mortality from, colon cancer in low or usual risk patients.
And just last week, a study was published in the Lancet in which 861 participants at high risk for colon cancer due to Lynch syndrome (hereditary non-polyposis colon cancer or HNPCC) were randomized to 600mg aspirin daily vs placebo for 2yrs and followed for close to 5yrs. The authors concluded that high dose aspirin for 2yrs was capable of reducing the risk of colorectal cancer in this high risk group for up to 5yrs.
Given the double-edged nature of aspirin, it's good to know that no adverse events were reported during the 2yrs that participants were receiving high dose aspirin, although one could certainly argue that the study group was too small and the study period was too short.
Today's take home point is this - it's time for the USPSTF to reconsider their stance regarding the use of aspirin as prophylaxis against colon cancer.