Geographic differences can give important clues to the etiology of cancer.
Look at the maps of various cancers below.
What are possible reasons for the observed differences in incidence rates?
What can migrant studies tell us about causes of a specific cancer?
Use Cancer Incidence in five Continents (CI5 IX) on the IARC website
Look for: Tables (PDF) on the left menu
- Summary tables
- By site (three-digit rubrics)
- Click Breast (C50)
Compare the age-standardized incidence rates (ASR (W), number in bold type) of breast cancer between women in Shanghai, China with that of women in Denmark, Norway and San Francisco Bay Area (California, USA - use rate for Non-Hispanic Whites).
What is the ratio of the highest to the lowest rate of breast cancer in these areas?