New Zealand’s melanoma rates highest in the world
Queensland researchers have found that New Zealand now has the highest per capita rates of invasive melanoma in the
world after overtaking Australia. Invasive melanoma is the deadliest form of skin cancer, which is capable of spreading
to other parts of the body.
The study was conducted by researchers from QIMR Berghofer Medical Research Institute in Brisbane and has been published
in The Journal of Investigative Dermatology.
The researchers found that while Australia’s melanoma rates have been declining since 2005, New Zealand’s rates are
still increasing and are not expected to start falling until about 2017.
Professor David Whiteman and his colleagues compared the rates of melanoma in six populations over a 30-year period from
1982 to 2011. The six populations were Australia, New Zealand, the United Kingdom, Norway, Sweden, and the caucasian
population of the United States. The researchers also used recent trends to predict invasive melanoma rates between 2011
and 2031.
They found that melanoma rates in New Zealand increased from about 26 cases per 100 000 people in 1982 to about 50 cases
per 100 000 people in 2011. Australia’s melanoma rates peaked at about 49 cases per 100 000 people in 2005 and declined
to about 48 cases per 100 000 people in 2011.
The researchers predict that New Zealand’s melanoma rates are currently peaking at about 51 cases per 100 000 people and
will start to decline from next year and reach about 46 cases per 100 000 people by 2031. Australia’s rates are expected
to keep falling to about 41 cases per 100 000 people by 2031.
Professor Whiteman, who led the study, said that while melanoma rates in New Zealand were expected to start declining
soon, rates in the UK, Sweden, Norway and the caucasian population of the United States were predicted to keep
increasing until at least 2022.
“We think the main reason why rates in Australia, and we hope New Zealand, will decline before the other populations is
that both countries have put a huge effort into primary prevention campaigns,” Professor Whiteman said.
“New Zealanders have become more ‘sun smart’ as they have become more aware of the dangers of melanoma, but more could
be done.”
The researchers found that although New Zealand’s average melanoma rates per 100 000 people were expected to start
falling soon, the overall number of invasive melanomas diagnosed in New Zealand each year would keep increasing.
Professor Whiteman said this was due to the ageing of the population, as well as overall population growth.
“Melanomas occur most commonly in older people. Unfortunately for older New Zealanders alive today, most will have
already sustained significant amounts of sun damage before the prevention campaigns were introduced. Those people are
developing melanomas now, many decades after the cancer-causing exposure to sunlight occurred,” he said.
“As New Zealand’s population ages, the number of melanomas diagnosed will continue to increase.
“While it’s good news that average melanoma rates in New Zealand should start to fall soon, the fact that the actual
number of cases will keep rising is bad news.
“It’s crucial that people of all ages protect themselves from the sun by wearing a hat and protective clothing, using
sunscreen, and, where possible, by staying out of the sun during the hottest part of the day.
“As the numbers of people being diagnosed with melanoma increase, governments will need to invest significant amounts of
funding in melanoma treatment in the years to come. A strong case can therefore be made to invest more in melanoma
prevention.”
The numbers of people dying from melanoma are also increasing across all six populations, but are highest in Australia
and New Zealand.
The study was funded by the National Health and Medical Research Council (NHMRC) of Australia.
ENDS