Taking aspirin everyday could boost cancer patients' chances of survival by up to 20%, say researchers. A study found aspirin can reduce the chance of death in colorectal, breast and prostate cancer, as well as stopping it spreading to other parts of the body.

Past studies have found aspirin can reduce the chances of getting cancer by 50%. However, researchers say there have only been "hints" aspirin could be helpful for patients that currently have cancer.

Scientists from the University of Cardiff combined results from five randomised trials and 42 observational trials, to find that taking a daily low-dose of aspirin reduces cancer deaths by 15 to 20%. It also reduces the spread of cancer to other parts of the body. The research was published in PLOS One.

"We're talking about a very low dose of aspirin here," Peter Elwood, leader of the research, told IBTimes UK. "The studies we looked at use 'junior aspirin', which is about 75mg in the UK – about a fifth of an everyday tablet."

Elwood says the research is the most conclusive to date that aspirin improves survival rates in cancer patients. "However, this is not a substitute. All other treatments must be continued with the daily doses of aspirin," he added.

The researchers also analysed the risks of aspirin; the most common being bleeding in the stomach. "We knew that around one in 1,000 people have a bleed in the stomach every year, and aspirin increases that chance by 60%," said Elwood. "We looked at the severity of the bleeding, and found no valid evidence that bleeding is fatal." He stressed that all patients should speak to their physician before using aspirin with their treatments.

The researchers say there is a desperate need for more detailed research to further confirm their findings. Elwood says the Add-Aspirin clinical trial – a nationwide aspirin trial for cancer patients – will assess whether aspirin increases the survival rate of 20,000 to 30,000 cancer patients. This is a significantly larger sample than any other study to date. However, the results are not expected for another ten years or so, Elwood says.