A study has shown that breast cancer patients who take aspirin are less likely to die of the disease.
The research showed that women with breast cancer could double their chance of survival by taking the drug twice a week.
The findings, published in the the Journal of Clinical Oncology, led charity Cancer Research UK to call for large-scale clinical trials.
Harvard Medical School researchers analysed 164 women diagnosed with breast cancer between 1976 and 2002 - finding that those who took aspirin two to five days a week showed the strongest reaction to the drug against the disease.
Women taking aspirin two to five days were 71% less likely to die of breast cancer and had a 60% reduced risk of the disease spreading. Those who took six to seven aspirins a week lowered the risk of spread by 43% and the risk of death from the disease by 64%.
Ed Yong, head of health information at Cancer Research UK, said: "We need large clinical trials to see if it can really save lives from breast cancer, and, if so, to work out what doses to use and how long to use the drugs for."