A daily dose of aspirin may reduce the risk of colorectal cancer for those who are predisposed to develop the condition, a new study finds.
Among participants who took two aspirins (600 milligrams) every day for at least two years, researchers found a 63 percent reduced incidence of colorectal cancers, compared with those who took a placebo.
All study subjects suffered from a genetic disorder known as Lynch syndrome. The results provide evidence for recommending aspirin as a drug to prevent cancer in those with this condition.
However, the researchers caution that patients should consult with their doctor before beginning to take aspirin regularly. The drug is known to increase the risk of stomach problems, including ulcers , the researchers said.
The study is published today (Oct. 27) in the journal the Lancet.
Lynch syndrome affects about 1 in 1,000 people. Those with the disorder are about 10 times more likely that the general population to develop cancer, particularly of the bowel and uterus, and often at a young age.
In the study, 861 subjects were randomly assigned to take either daily aspirin or a placebo for up to four years.
The first analysis of the trial data in 2007 showed no difference in colorectal cancer incidence between those who had taken aspirin and those who had not.
However, by 2010, there had been 19 new cases of colorectal cancers among those who had received aspirin, and 34 among those on placebo, meaning those in the aspirin group had an overall 44 percent reduced incidence of colorectal cancer. When researchers focused on the patients who took aspirin for at least two years (about 60 percent of the total), the effects of aspirin were even more pronounced: a 63 percent reduced incidence of colorectal cancer was observed with 23 bowel cancers in the placebo group, but only 10 in the aspirin group.
Looking at all cancers related to Lynch syndrome, including cancer of the endometrium (inner membrane of the uterus), almost 30 percent of the patients taking the placebo had developed a cancer compared to around 15 percent of those taking the aspirin.
Those who had taken aspirin still developed the same number of polyps, which are thought to be precursors of cancer, as those who did not take aspirin but they did not go on to develop cancer. It suggests that aspirin could possibly be causing these cells to destruct before they become cancerous, the researchers said.
The researchers plan to conduct another study to determine the optimum dose required for cancer prevention and to examine whether aspirin can reduce colorectal cancer among the general population.
The study involved scientists and clinicians from 43 centers in 16 countries. It was lead by led by researchers at Newcastle University in the United Kingdom.
Pass it on: Daily aspirin may reduce the risk of colorectal cancer for those with Lynch syndrome.