Worldwide burden of colorectal cancer: a review

Colorectal cancer is a major public health problem, being the third most commonly diagnosed cancer and the fourth cause of cancer death worldwide. There is wide variation over time among the different geographic areas due to variable exposure to risk factors, introduction and uptake of screening as well as access to appropriate treatment services. Indeed, a large proportion of the disparities may be attributed to socioeconomic status. Although colorectal cancer continues to be a disease of the developed world, incidence rates have been rising in developing countries. Moreover, the global burden is expected to further increase due to the growth and aging of the population and because of the adoption of westernized behaviors and lifestyle. Colorectal cancer screening has been proven to greatly reduce mortality rates that have declined in many longstanding as well as newly economically developed countries. Statistics on colorectal cancer occurrence are essential to develop targeted strategies that could alleviate the burden of the disease. The aim of this paper is to provide a review of incidence, mortality and survival rates for colorectal cancer as well as their geographic variations and temporal trends.