New York, March 5: Regular usage of aspirin is likely to reduce the overall risk of cancer, a reduction that primarily reflects a lower risk of colorectal cancer and other tumours of the gastrointestinal tracts, finds a new study. The results showed that people, who took either a standard or a low-dose aspirin tablet at least twice a week, had a 3 percent lower risk of cancer than those who didn't report regular aspirin use. The recurrent use of aspirin reduced the risk of colorectal cancer by 19 percent and the risk of any gastrointestinal cancer by 15 percent. No reduction was seen in the risk of breast, prostate or lung cancer. However, the use of aspirin may complement, but not replace the preventive benefits of colonoscopy and other methods of cancer screening, warned the researchers. "Our findings imply that aspirin use is expected to prevent a significant number of colorectal cancers beyond those that would be prevented by screening and may have even greater benefit in settings in which the resources to devote to cancer screening are lacking," said one of the researchers Andrew Chan, associate professor at Harvard University in US. A regular usage of aspirin could prevent around 30,000 gastrointestinal tract tumours in the US each year and could prevent an additional 7,500 colorectal tumours among US adults over 50 who have endoscopic screening and 9,800 among the 30 million who are not screened, the researchers estimated. The research team analysed 32 years of data from almost 136,000 participants in the Nurses' Health Study and the Health Professionals Follow-up Study. The findings of the study, published Online First in JAMA Oncology, stressed that patients should be well informed about the potential side effects of regular aspirin treatment and continue their regular screening tests. But, aspirin should not be viewed as a substitute for colonoscopy or other cancer screening tests, the researchers concluded.