Although there are both beneficial and detrimental effects of ultraviolet radiation (UVR), excess exposure can be damaging to health.

 Skin cancer is the most common cancer in New Zealand, with New Zealanders at high risk of developing a skin cancer during their lifetime. Our skin cancer rates are among the highest in the world. Melanoma incidence rates in Australia and New Zealand are around four times as high as those found in Canada, the USA and the United Kingdom(1).

New Zealand’s high rates of skin cancer are due to a number of factors including the strength of the UVR that reaches New Zealand during the daylight savings months, low ozone values, our outdoor lifestyle, our tendency to ‘seek the sun’, and the high proportion of people with fair skin in our population. Light skin type, large numbers of moles and excessive sun exposure (particularly intermittent episodes of sunburn), especially in childhood and adolescence, are the major predictors of melanoma risk.

Yet, skin cancer is readily preventable. Over 90% of all skin cancer cases in high UVR environments like New Zealand are attributed to excess exposure to UVR(2). That is why the Cancer Society sees the promotion of skin cancer prevention and early detection as a central component of its work. 

 About Skin Cancer

 Skin cancers include:

• Melanoma: the least common but the most serious form of skin cancer.
• Squamous cell carcinoma (SCC): easily treated if found early but can be fatal if left untreated.
• Basal cell carcinoma (BCC): the most common and least dangerous skin cancer. BCC can be serious, including surgery and scarring, if left untreated.

Skin Cancer Facts and Figures

 Skin cancer is by far the most common cancer affecting New Zealanders. The total number of new melanoma and non-melanoma skin cancer cases amount to around 80 percent of all new cancers each year. 

In 2005, the year for which most recent figures are available, there were 2017 melanoma registrations (1107 males and 910 females). Melanoma was also the third most commonly registered cancer among both men and women. 

There are also an approximate 67,000 new non-melanoma skin cancer (NMSC) cases each year. However, providing an exact figure for the number of non-melanoma skin cancers (basal cell carcinoma and squamous cell carcinoma) is difficult as, unlike melanoma, they are not required to be notified under the Cancer Registry Act 1993. 

Like other cancers, melanoma occurs most often in older people, but can also affect younger people. Among males, 25 to 44 years, melanoma was the leading cancer (124 registrations), while among females aged 25 to 44 years it was the second most common cancer (206 registrations).

Melanoma mortality rates are relatively low relative to registration rates. Each year, there are around 250 deaths from melanoma, and around 100 deaths from non-melanoma skin cancers. In 2005, 269 people died from melanoma (156 males, 113 females). Mortality rates for both melanoma and NMSC are higher than Australian rates.

There are ethnic differences in melanoma incidence and mortality. In 2005, among Maori, there were 22 cases and 6 deaths, while among Pacific there were 8 cases and 0 deaths from melanoma. While Maori and Pacific people have significantly lower melanoma incidence rates, melanoma tends to be detected at a later and potentially more dangerous stage among these populations. Melanoma rates may be increasing among Maori, although rates based on small numbers are unreliable. 

Refer to New Zealand Health Information Service.

 

References

1. International Agency for Research on Cancer. IARC Monographs on the evaluation of carcinogenic risks to humans. Solar ultraviolet radiation. Lyon: International Agency for Research on Cancer, 1992.
2. Armstrong BK. How sun exposure causes skin cancer. In: Hill D, Elwood JM, English DR, Eds. Prevention of Skin Cancer. Dordrecht: Kluwer Academic Publishers, 2004.

 

Further information