Trends in the incidence of non-melanocytic skin cancer (NMSC) treated in Australia 1985-1995: are primary prevention programs starting to have an effect?

Abstract

Non-melanocytic skin cancer (NMSC) is the most common cancer in Australia, but data on its incidence are not routinely collected by cancer registries. National surveys were conducted in 1985, 1990 and 1995 to estimate NMSC incidence. Trends in incidence between 1985 and 1995 have been examined to determine the impact of primary prevention campaigns aimed at controlling skin cancer in Australia. National random household surveys of Australians aged over 13 years were used to estimate NMSC incidence in 1985, 1990 and 1995. Age- and sex-specific rates by survey year were modelled using Poisson regression. Basal cell carcinoma (BCC) rates in 1995 were 788 per 100,000, an increase of 19% since 1985. Squamous cell carcinoma (SCC) rates rose by 93% over the same period, from 166 to 321 per 100,000. The ratio of BCC:SCC changed from 4:1 in 1985 to 2.5:1 in 1995. BCC rates in latitudes <29 degrees S remained at about 3 times those in latitudes >37 degrees S over the decade. The ratio of SCC incidence between these latitudes changed from around 7:1 to 3:1 over the same period. Although NMSC incidence rates continue to rise, there have been reductions in BCC observed in younger age groups. Incidence rates of NMSC continue to rise in Australia, but there is evidence of a reduction in BCC incidence in younger cohorts. This is evidence that public health campaigns to reduce sun exposure may be having a beneficial effect on skin cancer rates.