Otago study finds older people underestimate risk of deadly melanoma

New Zealanders aged 60 and over appear to wrongly believe they are at low risk of the fatal form of skin cancer melanoma, according to a new University of Otago study conducted for the Cancer Society of New Zealand.

Yet the incidence of and deaths from melanoma in middle-aged to elderly people in New Zealand has been rising.

Lead researcher Dr Mary Jane Sneyd, from the University of Otago’s Hugh Adam Cancer Epidemiology Unit, says the Cancer Society of New Zealand, which funded the study, sought to explore the attitudes towards melanoma across the age-groups.

Dr Sneyd looked at the attitudes of a random sample of 777 men and women aged 40 to 70 and found that participants aged 60-plus seem to regard themselves at lower risk of melanoma than younger people, and yet their risk is considerably higher.

“What we found is that in general, people are estimating their risk reasonably well on the basis of their phenotype, such as that if you are fair or red haired, and blue eyed you have a greater risk, and if you have dark hair, darker skin colour and dark eyes you have a lower risk,” she says.

“But, as people got older, they saw themselves as having lower risk of melanoma and yet the risk of melanoma goes up greatly with age – as with most cancers.”

Data published in 2011 by the Ministry of Health showed that in 2008, of all new melanomas diagnosed, 58.8% occurred in people aged 60 plus, and only 2.4% occurred in people under 30.

“Anecdotally, it seems that a lot of people seem to think that melanoma is a young persons’ disease. That is probably because the media have often concentrated on this age group, and promotion of sun safety seems to be aimed at the young,” Dr Sneyd says.

“Yet cancer is actually quite rare in young people, it is just that when young people get cancer, melanoma is one of the most common types and it can be deadly.”

She says no matter what age people are, they need to understand that with early diagnosis, death from melanoma is preventable. If it is left too long, and the lesion becomes too thick, this greatly decreases chances of survival of this cancer.

It was also originally thought that excessive exposure to sun only as a child and adolescent increased the chance of developing melanoma. But evidence increasingly shows that over-exposure to sun in older years also continues to increase the risk of melanoma.

“Early diagnosis of suspicious lesions is crucial and excessive sun exposure at any age should be avoided,” she says.

Ministry of Health figures from 2008 show that melanoma at that time was the fourth most common cancer to be diagnosed, and the sixth most common cause of cancer death.

Other University of Otago researchers who worked on the study were Dr Claire Cameron and Assistant Research Fellow Aimee Ward.