The location of a population may have a profound influence on its incidence of a given cancer. Standardized tumour registries have allowed detailed comparisons. Some commonly quoted examples include:
For these examples, it is thought that exposure to an environmental agent in a particular location results in the increased risk, e.g. sun exposure in Australia. In support of this is the evidence from migrant studies. Immigrants commonly acquire with successive generations the risk for a given cancer related to their new location.
Yet, it is often hard to extricate geographical factors from other differences which characterise communities, e.g. ethnic origin or national conventions. Hence, Mormons in Utah in the U.S. have a lower incidence of respiratory, gastrointestinal and genital cancer than other communities in the same state. Equally, the death rate from breast cancer is higher in Denmark than Sweden despite their close apposition; social differences in the number or pregnancies and breast feeding may have a role.
Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.