Men's chances of getting bowel cancer in Great Britain have doubled since the mid 70s - according to new figures released today by Cancer Research UK.

Their lifetime risk has increased from around one in 29 to around one in 15. And for women bowel cancer risk has risen by more than a quarter going from one in 26 to one in 19.

In 2008 there were around 21,500 cases of bowel cancer diagnosed in men compared with around 11,800 cases in 1975. There were around 17,400 cases of bowel cancer in British women in 2008 compared with around 13,500 in 1975.

But there is good news about survival. Half of all patients diagnosed with bowel cancer now survive the disease for at least 10 years (around 50 per cent) – double the number who would have done so in the early 70s (around 23 per cent).

Other figures, released today by Cancer Research UK, show that men generally are more at risk of getting cancer – 42.2 per cent develop the disease compared to 38.8 per cent of women.

These calculations are based on a new method of predicting the lifetime risk of developing cancer – published today by the charity's researchers in the British Journal of Cancer. This method is a far more accurate way of calculating lifetime risk as it takes into account people who may get cancer more than once in their lifetime to ensure they are not counted twice. The method also adjusts for the fact that people can die from something other than cancer before they have a chance to be diagnosed with the disease.

Professor Peter Sasieni, study author and Cancer Research UK epidemiologist, said: "As people are living longer the numbers getting cancer have increased and the lifetime risk of developing bowel cancer has gone up.

"Lifetime risk is a complex issue but it allows us to estimate the sheer number of people who will develop cancer by predicting the chance of getting the disease between birth and death based on today's cancer incidence rates and death rates from cancer and other causes. For some cancers including bowel – the risk of cancer in the next 10 years will be much higher for people in their 50s and 60s. But if someone reaches their late 70s and hasn't yet developed the disease then their risk of getting it during the rest of their lifetime is lower than their risk at birth."

Sara Hiom, director of health information at Cancer Research UK, said: "An ageing population as well as changes in lifestyle have both led to more people developing cancer than a generation ago.

"But even though the chances of getting the disease have increased in the population there are many ways that people can cut their own risk. You can reduce your risk of bowel cancer by keeping a healthy weight, being physically active, eating a healthy diet that's high in fibre and low in red and processed meat, cutting down on alcohol and not smoking. It's also important to take up the opportunity to take part in bowel screening when invited.

"And the good news is that even though more people are developing bowel cancer, more people are surviving the disease. There are many reasons for this including earlier diagnosis improved surgical techniques and better treatments many of which have been developed through our research."

Article: Sasieni P et al: What is the lifetime risk of developing cancer? The effect of adjusting for multiple primaries. BJC 2011; doi:10.1038/bjc.2011.250