Aspirin may double the chances of survival for patients with gastrointestinal cancers, according to the results of a new study recently presented at the 2015 European Cancer Congress in Vienna, Austria.
This research, led by Dr. Martine Frouws of Leiden University Medical Centre in the Netherlands, adds to growing evidence suggesting aspirin may be useful in the prevention and treatment of cancer.
Last month, Medical News Today reported on a study suggesting aspirin may reduce the risk of colorectal cancer, while a more recent study claims aspirin may help boost treatment response in patients with breast, skin and bowel cancers.
For their study, Dr. Frouws and colleagues set out to determine how aspirin impacts the survival of patients with tumors in the gastrointestinal (GI) tract - namely the rectum, colon and esophagus. This is the first time a study has simultaneously assessed survival data by different GI locations, according to the authors.
The study included 13,715 patients who received a GI cancer diagnosis between 1998 and 2011. They were followed up for a median of 48.6 months. Of these patients, 42.8% had colon cancer, 25.4% had rectal cancer and 10.2% had cancer of the esophagus.
To determine how aspirin use after a GI cancer diagnosis impacted the overall survival of these patients, the researchers linked patient data with drug dispensing information from the PHARMO Institute in Utrecht, the Netherlands.
"In this study we analyzed each separate prescription per patient, and therefore we were able to achieve a more exact estimate of the effect of aspirin on cancer survival," notes Dr. Frouws.
Post-diagnosis aspirin users twice as likely to survive GI cancer
Overall, around 30.5% of patients used aspirin prior to GI cancer diagnosis, 8.3% only used aspirin after their diagnosis, while 61.1% did not use aspirin.
Across all cancers, around 28% of patients survived for at least 5 years.
Compared with patients who used aspirin before their cancer diagnosis and those who did not use the medication, patients who used aspirin after their diagnosis were twice as likely to survive, according to the results.
This finding remained even after the team accounted for potential confounding factors, including age, sex, cancer stage, cancer treatment and the presence of other medical conditions.
While the exact mechanism underlying the anticancer effect of aspirin is unclear, the researchers suggest it could be down to its antiplatelet properties. They explain that circulating tumor cells (CTCs) are believed to use platelets - a component of blood - to shield themselves from the immune system. Because aspirin blocks the function of platelets, this may expose CTCs, leaving them open to attack.
Though the optimal dosage and duration of aspirin use and its effect on GI cancers need to be investigated in further research, the team believes they have uncovered a potential treatment option that could reach a wide number of patients.
"Given that aspirin is a cheap, off-patent drug with relatively few side effects, this will have a great impact on health care systems as well as patients," says Dr. Frouws, adding: