Trends in site-specific melanoma in Queensland: are we witnessing the impact of public health campaigns? (#128)
Aims: To examine melanoma incidence trends by body site, sex and age at diagnosis or body
site and morphology.
Methods: Population-based data on invasive melanoma cases (n=51,473) diagnosed between
1982 and 2008 were extracted from the Queensland Cancer Registry. Directly age-standardised incidence rates were calculated and Joinpoint regression models were used to fit trend lines.
Results: For all sites combined significant decreasing trends of 3.8% per year (p < 0.001) for males and 3.4% per year (p=0.043) for females were observed. In males under the age of 40 years, body sites such as the trunk recorded significant decreasing trends (-6.0%, p < 0.001) and decreasing trends were observed for the upper limbs/shoulder in both males and females in this age group. Overall decreasing trends were also observed for males (-2.6%, p 0.043), and females (-1.7%, p 0.020), in the 40 to 59 year age group. Sites such as the trunk and upper limbs/shoulders in males again recorded significant decreases in more recent years. However, in the 60 and over age group, the incidence of melanoma is continuing to increase at all sites (apart from the trunk) for males and on the scalp/neck and upper limbs/shoulders for females. Rates of nodular melanoma are currently decreasing on the trunk and lower limbs. In contrast, superficial spreading melanoma is significantly increasing on the scalp/neck and lower limbs, along with substantial increases in lentigo maligna melanoma since the late 1990s at all sites apart from the lower limbs.
Conclusions: In this large study we have observed significant decreases in rates of invasive
melanoma in the younger age groups, particularly for body sites that are less frequently exposed. These results may provide some indirect evidence of the impact of long-running primary prevention campaigns.