Statins almost halve the odds of dying from cancer, British scientists claim.
A study of almost 23,000 cancer patients found that those who happened to have high cholesterol were up to 47 per cent less likely to die of the four most common forms of the disease.
Researchers are convinced that this was because they were taking statins - which they claim provided a crucial, protective effect against tumour growth.
The discovery at Aston University in Birmingham will add to calls for the cholesterol-lowering pills to be routinely used in cancer treatment.
It backs up a slew of recent studies which have shown that patients taking statins were far less likely to die from the illness.
Only last month a team from the Institute of Cancer Research in London found that the pills reduce the risk of breast cancer returning by up to 50 per cent.
And two major American studies last year showed they slashed the risk of dying from cancer by between 22 per cent and 55 per cent, depending on the type of tumour.
Researchers believe that cholesterol in the blood fuels tumour growth and encourages cancer to spread and return.
But as statins reduce cholesterol levels, they help to prevent the cancer becoming far more deadly.
For this latest study, researchers analysed information from 22,677 people suffering from lung, breast, prostate and bowel cancers, taken from a database of nearly 1million patients. All had been admitted to hospitals in the UK with cancer between January 2000 and March 2013, and anonymised information on their other health conditions - including whether they had high cholesterol - was available.
After taking into account other factors which might influence death rates, including age, gender, and ethnicity, researchers found cancer patients were less likely to die early if they had a diagnosis of high cholesterol than if they did not. The study says statins are associated with a 47 per cent lower risk of death from prostate cancer, a 43 per cent lower risk in those with breast cancer, a 30 per cent lower risk in bowel cancer cases, and a 22 per cent lower risk in lung cancer patients.
Some nine out of ten of the patients who had been diagnosed with high cholesterol were on statins.
The findings were presented at a European Society of Cardiology conference in Florence yesterday.
Around 7 million Britons take statins to lower cholesterol, making them the most commonly prescribed drugs in the UK.
They cost just 3p a day and work by stopping the accumulation on blood vessel walls of cholesterol deposits which trigger heart attacks and strokes.
There has been growing evidence they also provide other key health benefits, and could even slash the risk of Alzheimer's disease. But some doctors remain sceptical of the pills because they can cause debilitating side-effects including muscle pain and diabetes.
Dr Rahul Potluri, senior author of this latest study, said that in terms of their effect on cancer, "other mechanisms of statins could exist which have not been shown yet" and that there should now be a clinical trial to examine whether statins can benefit cancer patients whether or not they have high cholesterol.
Dr Potluri suggested further studies could show whether other medications for cardiovascular health - such as beta-blockers and ACE inhibitors - could also have a similar, protective effect on cancer patients.
But Dr Tim Chico, a cardiovascular medicine specialist at the University of Sheffield, said the findings were "extremely preliminary" and "should not influence current practice".