The global cancer burden is set to surge more than 75% by 2030, according to new research published Online First in the Lancet Oncology. The rise is predicted to be even larger in the developing world, with the poorest countries experiencing a projected increase of more than 90%.
The study, led by Dr Freddie Bray of the International Agency for Research on Cancer (IARC) in Lyon, France, is the first to examine how the current and future patterns of incidence and mortality of different types of cancer vary between countries with different levels of development, as measured by their Human Development Index (HDI).
Although incidence rates and the burden of some types of cancer (such as cervical cancer and stomach cancer) appear to be mainly declining in countries transitioning socially and economically towards higher levels of human development, the reduction is likely to be offset by a substantial increase in the types of cancer more associated with a so-called “Westernised” lifestyle, including breast, prostate, and colorectal cancer.
“Cancer is already the leading cause of death in many high-income countries and is set to become a major cause of morbidity and mortality in the next decades in every region of the world; this study serves as an important reference point in drawing attention to the need for global action to reduce the increasing burden of cancer”, states Dr Bray.
The study used data from GLOBOCAN, a database compiled by the International Agency for Research on Cancer (IARC) comprising of estimates of cancer incidence and mortality in 2008 in 184 countries worldwide . The researchers describe how patterns of the most common types of cancer varied according to four levels of human development. These findings were then used to project how the cancer burden is likely to change by 2030 in light of predicted changes in population size and ageing, as well as the changing trends in incidence rates of six of the most common types of cancer in countries with medium, high and very high levels of HDI.
Countries with a low HDI (predominantly countries in sub-Saharan Africa) currently experience a high incidence of cancers associated with infection, particularly cervical cancer and, dependent on the region or country, liver cancer, stomach cancer and Kaposi’s sarcoma. By contrast, countries with a higher HDI (such as the UK, Australia, Russia, and Brazil) have a greater burden of cancers more commonly associated with smoking (lung cancer), reproductive risk factors, obesity and diet (female breast, prostate, and colorectal cancer).
While increasing living standards in the coming decades in lower-HDI countries may lead to a decrease in the burden of some infection-related cancers, the authors warn that, irrespective of future developments, there may be a surge in the types of cancer which currently affect mainly higher-HDI countries. They predict that demographic changes as well as changing trends in cancer incidence rates could lead to a large increase in the cancer burden in lower or medium HDI countries, with medium HDI countries (such as South Africa, China, and India) predicted to experience an increase of 78% in the number of cancer cases by 2030, and low HDI countries predicted to undergo a 93% increase over the same period. The study also revealed the following trends: