Published on: 22nd February 2017
Case Study 14
David M Fraser, University of Dundee; Prof Frank Sullivan, University of Toronto
Prof Alastair Thompson, MD Anderson Cancer Center, Texas; Prof Colin McCowan, University of Glasgow
By analysing information collected by the NHS, researchers were able to provide evidence that suggests that aspirin could improve survival of women diagnosed with breast cancer, leading to a UK-wide clinical trial.
People often have more than one disease requiring long term use of medication. Occasionally this can result in clinicians and researchers gathering information that suggests that a medicine used to treat one disease may also be beneficial in treating another disease. A few small research studies started to suggest that patients who took aspirin after they had been diagnosed and treated for breast cancer had better survival outcomes than those who were not given aspirin as part of their medication. However, not all studies showed this link. Researchers from the Universities of Dundee and Glasgow used data from the 400,000 population of Tayside in Scotland to see if they could find evidence to support this connection.
The NHS in Scotland collects information about people who are diagnosed with and lose their lives to cancer each year, as well as the drugs they are prescribed. This information can be linked and used by researchers to investigate whether a group of patients given a particular drug are more likely to survive compared to a group of patients who are not taking the drug.
In this study the researchers compared women with breast cancer who were taking aspirin for another medical condition and patients who were not taking aspirin. The researchers obtained ethical approval to study the records of women within Tayside who were diagnosed with breast cancer between 1998 and 2008. The health records provided information on the type of breast cancer, the treatment patients received and whether the patients had died.
The study followed women until they passed away or for an average of over 5 and a half years. It showed that women who took aspirin after their breast cancer diagnosis were 47% less likely to die at any given point in time than those who were not taking aspirin. The researchers did not have access to the medical information that would have allowed them to know why patients were given aspirin, but in general the patients were prescribed a low dose (lower than over the counter aspirin used for pain relief) which is often given to people who have had heart attacks or strokes.
Although this study provided further evidence supporting the theory that aspirin helps survival in women diagnosed with breast cancer, it is not conclusive proof that giving cancer patients aspirin will definitely help their survival. It may be that there’s something else more common in women who take aspirin after having had breast cancer that makes them live longer. However, because this is one of a number of studies which has shown the link between taking aspirin and longer survival after breast cancer diagnosis, Cancer Research UK are now sponsoring a UK-wide clinical trial to establish whether adding a low dose of aspirin to other breast cancer medications can improve survival.
To find out more about the Cancer Research UK trial, visit www.cancerresearchuk.org/about-cancer/find-a-clinical-trial/a-trial-looking-at-whether-aspirin-can-stop-cancer-coming-back-after-treatment-add-aspirin.