How does each country measure up?
The study also analysed the years of life lost to cancer. This was calculated by using the age at which cancer patients died from their disease and the average life expectancy for the general population at that age to estimate how many years are lost to cancer.
This approach allowed researchers to examine whether certain risk factors are causing deaths more prematurely, enabling them to better measure the impact of cancer deaths on society – for example, a cancer death at age 60 will result in more years of life lost than a death at age 80.
Researchers found that the four preventable risk factors result in over 30 million years of life lost to cancer each year.
Of those years, smoking tobacco had by far the biggest impact – leading to 20.8 million years of life being lost to cancer each year.
However, preventable risk factors were predominantly associated with different cancer types in different countries.
For example, for men in India, most smoking-associated years of lives lost were attributed to head and neck cancer. For women in India and South Africa, gynaecological cancer caused the most years of lives lost. But in every other country, tobacco smoking caused the most years of life to be lost to lung cancer.
The higher number of years of life lost to head and neck cancer in men in India could be explained by tobacco use being different to the UK, with smokeless or chewed tobacco products more common than smoking cigarettes.
Cervical screening is less comprehensive in India and South Africa than in some other countries like the UK and US, which would explain why there are more years of life lost from gynaecological cancers due to HPV infection in India and South Africa.
Cervical cancer can be largely prevented by screening and HPV vaccination, which are more established in the UK and US, with the HPV vaccination in the UK reducing cervical cancer rates by almost 90% in women in their 20s who were offered the vaccine aged 12-13.
A global effort
Across the globe, cancer is increasingly impacting low- and middle-income countries. Cancer Research UK analysis shows that new cancer cases are expected to rise by around 400%, from 0.6 million to 3.1 million per year in low-income countries over the next 50 years. Very-high-income countries like the UK are projected to see an increase of around 50% over the same time period.
“Seeing how many years of life are lost to cancer due to these risk factors in countries around the world allows us to see what certain countries are doing well, and what isn’t working,” says Dr Judith Offman, senior lecturer in cancer prevention and early detection at QMUL, who worked on the study.
“Globally, someone dies every two minutes from cervical cancer. 90% of these deaths occur in low- and middle-income countries and could be cut drastically with comprehensive screening and HPV vaccination programmes.
“We know that HPV vaccination prevents cervical cancer. This, coupled with cervical screening, could eliminate cervical cancer as a public health problem. Countries need to come together on this ambition.”
Cancer Research UK is attempting to address this through its International Cancer Prevention programme, which works with partners in low- and middle-income countries to increase access to the HPV vaccine and support effective tobacco control measures.
In England, Cancer Research UK is launching its Manifesto for Cancer Research and Care on November 28 to outline how the UK government can transform cancer care and survival in this country, and help other countries around the world save more lives from cancer.
The manifesto will provide a blueprint of actionable policies that any political party can adopt to improve outcomes for cancer patients.