Although the figure that one in two people in the UK born after 1960 are at risk sounds frightening, the main reason for this increase is actually a good one. It’s because more and more people are living long enough to get cancer.
Cancer is primarily a disease of old age, with more than 65 per cent of cancer cases diagnosed in people aged over 65. The longer you live, the more likely it is that you will get cancer at some point, and, thankfully, people are beginning to live a lot longer. So the majority of the increase in lifetime risk of cancer is due to increasing longevity rather than an increase in cancer incidence.
“Lung cancers have become less common, while breast, and bowel cancers have become more common.”
But it’s also true that some cancers are becoming more common. As lifestyles have changed, fewer people are smoking, but more people are overweight. As a result, lung cancers have become less common, but breast, and bowel cancers have become more common. And screening programs and other improvements in diagnosis are also picking up more non-fatal cancers that may otherwise not have been spotted. This has led to an increase in breast, bowel and prostate cancers.
We also updated the methodology used when calculating the new lifetime cancer rate. The 1 in 3 figure was calculated using current age-specific cancer rates throughout a 'lifetime', whereas the new figure applied cancer rates to individuals born in a certain year and tracked with them as they aged.
“Cancer rates are highest in Europe and North America, and lowest in sub-Saharan Africa and India.”
The 1 in 3 figure had already been out of date for some time, and even using the older methodology the lifetime risk would be 45% for men and 41% for women. But the new method gives 53.5% for men and 47.5% for women born in 1960.
It’s difficult to compare this figure to those in low and middle-income countries, because cancer incidence data is simply not available in most of these areas. But from a number of quality cancer registries in low and middle income countries, it’s clear that cancer rates are highest in Europe and North America, and lowest in sub-Saharan Africa and India. However, there is also a tremendous amount of variation for different cancer types. For example, liver cancer is most common in East Asia and West Africa, and stomach cancer is most common in Japan, Mongolia and China. Meanwhile breast, prostate and bowel cancers are the most common in high-income countries.