(click on image to enlarge)The blue shows lower breast cancer and the red or pink are higher. The lighter areas such as nevada and Alaska simply show a low population density so don't read well.
The prevalence of various cancers are related to latitude, its resulting solar light levels and vitamin D production.
This map of North America shows the distribution of Breast cancer
Although I don't have maps for the UK, Europe or Canada...one can assume the results are similar or worse at higher latitudes. Consider that London or Berlin are farther north then the US, so it implicates all of Canada and much of Europe. The UVB spectrum which produces Vitamin D and high test vitamin D (calcitriol) in the skin, is only now strong enough to be effective in helping with our skin.
Note also how the cancer rates are lower in the mountainous areas where sunlight uvb intensity and vitamin D production would be higher due to a higher elevation for that latitude. And finally make note of higher rates in the south or west where elderly populations may retire or the small areas of red where they may seek cancer treatment. Many of these results could be assumed to carry over to Europe and Asia with similar northern latitudes and the same in the southern hemisphere including Australia,New zealand, Argentina and South Africa..
