A study found that rates of invasive melanoma, the deadliest form of skin cancer, have started to decline in Australia and are predicted to keep falling over the next 15 years.
Researchers at QIMR Berghofer Medical Research Institute have found that Australia no longer has the highest per capita rates of invasive melanoma in the world, after being overtaken by New Zealand.
Researchers 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 found that melanoma rates in Australia increased from about 30 cases per 100,000 people in 1982 and peaked at nearly 49 cases per 100,000 people in 2005. The rates then declined to about 48 cases per 100,000 people in 2011. Invasive melanoma rates in New Zealand reached about 50 cases per 100,000 people in 2011.
Professor David Whiteman, who led the study, said Australia was the only one of the six populations where melanoma rates had begun to fall overall.
“We think the main reason for this decline is that Australia has put a huge effort into primary prevention campaigns since the 1980s,” Professor Whiteman said.
“Australians have become more ‘sun smart’ as they have become more aware of the dangers of melanoma and other skin cancers. Schools, workplaces and childcare centres have also introduced measures to decrease exposure to harmful UV radiation.”
“This has contributed to a decline in melanoma rates in people under the age of about 50.”
“Unfortunately, rates of melanoma are still increasing in people over the age of about 50. This is probably because many older people had already sustained sun damage before the prevention campaigns were introduced, and those melanomas are only appearing now, many decades after the cancer-causing exposure to sunlight occurred.”
Despite the fall in average melanoma rates per 100,000 people, the overall number of invasive melanomas diagnosed in Australia is still rising and is expected to increase from 11,162 cases per year from 2007-2011, to 12,283 cases per year from 2012-2016.
Professor Whiteman said this was due to the ageing of the Australian population, as well as overall population growth.
“Melanomas occur most commonly in older people. As Australia’s population ages, the number of melanomas diagnosed will continue to increase,” he said.
“The picture in Australia at the moment is mixed. While it’s good news that average melanoma rates have started to fall, the fact that the actual number of cases is still rising is bad news.”
The Australian Cancer Research Foundation has supported cancer research at QMRI Berghofer by providing three grants, totalling AUD 6.65million towards cutting edge cancer research equipment and technology.