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The United States, Canada, countries
of Western Europe, and Australia specifically Sweden
but excluding Italy and Greece, are the countries with
the highest incidence, prevalence, and mortality rates
of prostate cancer in the world. These countries are
considered high-risk countries. Countries in Asia, particularly
Japan, are considered low-risk countries. Researchers
attribute prostate cancer risk based on location to
three factors: UV light, testing prevalence, and traditional
diet.
UV Light and Prostate Cancer
Risk
Some researchers believe that insufficient exposure
to UV rays may lead to higher risks of prostate cancer
and higher prostate cancer mortality rates. Countries
within high latitudes such as Canada and Sweden have
the highest prostate cancer mortality rates in the world.
Black men living in America also have uncharacteristically
high rates of aggressive prostate cancer and prostate
cancer-related mortality.
UV light stimulates the production
of Vitamin D, which some researchers believe provides
a protective effect when present in adequate (not excessive)
quantities. The lower levels of UV ray exposure in high-latitude
countries may not provide the sufficient exposure its
inhabitants require. African-American men who live close
to the equator may not receive sufficient exposure due
to increased levels of skin melanin which blocks UV
rays.
PSA Testing and Prostate
Cancer Risk
Some doctors believe that all men, if given enough time,
will eventually develop prostate cancer. Some countries,
particularly the United States, place a high emphasis
on testing. Therefore, the countries that advertise
the importance of yearly prostate specific antigen (PSA)
tests and digital rectal exams (DRE’s) beginning
at ages 40 through 50, are much more likely to have
higher rates of prostate cancer within their geographic
area.
Countries that do not place a high
emphasis on testing may have prostate cancer deaths
that go unrecorded. Because most cases of prostatic adenocarcinoma, the most common type of prostate cancer,
grow very slowly, many men may die with prostate cancer
due to other causes rather than from prostate cancer.
High-risks countries, such as America, tend to place
emphasis on early testing, which may inflate their rates
of incidence.
Traditional Diet and Prostate
Cancer
Asian men seem to have the lowest chances of developing
prostate cancer. Japan has the lowest rates in world.
Some researchers attribute these numbers to the traditional
rural Japanese diet which is based on fish rather than
red meat. Supporting this theory are the rising levels
of the disease which coincide with the westernizing
of the Japanese diet. Additionally, Asian men who immigrate
to the United States have incidence rates similar to
the majority population.
European men from countries with
relatively low rates of the disease, in part due to
traditional diet which focuses on olive oil and vegetables,
also begin to display higher levels of prostate cancer
after immigrating to the Unites States. Click here to
read more about Prostate
Cancer Risk and Diet.
Other factors such as pollution,
however, may increase chances for the disease, but at
this time, no conclusive studies exist that can correlate
other location factors.
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