Aspirin Helps Block Hereditary Colon Cancer

It’s been shown that regular aspirin consumers are less likely to develop colorectal cancer, but the preventive effect hasn’t been quantified in any way, until now.  The online edition of Lancet carries a report of a study that goes a long way towards doing this.  It was conducted in patients with Lynch syndrome, which is estimated to account for about 3% of all colorectal cancer cases.

Lynch syndrome is a rare inherited condition that raises a person’s risk of developing colon cancer, as well as other cancers in various organs. Roughly half of people with lynch syndrome develop cancer, usually in the colon or uterus.  The study, done in numerous centers internationally, randomized 861 Lynch syndrome patients to take daily aspirin (600 mg a day) or a placebo for up to 4 years.

After an average of 56 months, 18 of 427 aspirin-treated patients and 30 of 434 placebo patients had developed colorectal cancer, a reduction of 37% with aspirin relative to placebo.  When multiple cancers in individual patients were included in the analysis, the protective effect was statistically significant: a 44% reduction.  And for those subjects who had completed 2 years in the study, the reduction with aspirin amounted to 59%.

These results strengthen the evidence that aspirin (and other non-steroid anti-inflammatory drugs, or NSAIDs) can inhibit colorectal adenomas and cancer, in some way.  Until now, it hasn’t been considered feasible to prescribe such drugs to prevent cancer.  But now, in Lynch syndrome patients, where the chances of cancer are so high, the risk/benefit ratio for aspirin use is sufficiently low for specialists to recommend their regular use.  Further research is needed before such a recommendation can be made for the general population, however.