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Background Thyroid cancer incidence has been increasing worldwide. Some suggest greater ascertainment of indolent tumours is the only driver, but others suggest there has been a true increase. Increases in Australia appear to have been among the largest in the world, so we investigated incidence trends in the Australian state of Queensland to help understand reasons for the rise. Methods Thyroid cancers diagnoses in Queensland 1982-2008 were ascertained from the Queensland Cancer Registry. We calculated age-standardized incidence rates ( ASR) and used Poisson regression to estimate annual percentage change ( APC) in thyroid cancer incidence by socio-demographic and tumour-related factors. Results Thyroid cancer ASR in Queensland increased from 2·2 to 10·6/100 000 between 1982 and 2008 equating to an APC of 5·5% [95% confidence interval ( CI) 4·7-6·4] in men and 6·1% (95% CI 5·5-6·6) in women. The rise was evident, and did not significantly differ, across socio-economic and remoteness-of-residence categories. The largest increase seen was in the papillary subtype in women ( APC 7·9%, 95% CI 7·3-8·5). Incidence of localized and more advanced-stage cancers rose over time although the increase was greater for early-stage cancers. Conclusion There has been a marked increase in thyroid cancer incidence in Queensland. The increase is evident in men and women across all adult age groups, socio-economic strata and remoteness-of-residence categories as well as in localized and more advanced-stage cancers. Our results suggest 'overdiagnosis' may not entirely explain rising incidence. Contemporary aetiological data and individual-level information about diagnostic circumstances are required to further understand reasons for rising thyroid cancer incidence. [ABSTRACT FROM AUTHOR]

Background An examination of melanoma incidence according to anatomical region may be one method of monitoring the impact of public health initiatives. Objectives To examine melanoma incidence trends by body site, sex and age at diagnosis or body site and morphology in a population at high risk. Materials and methods Population-based data on invasive melanoma cases ( n = 51 473) diagnosed between 1982 and 2008 were extracted from the Queensland Cancer Registry. Age-standardized incidence rates were calculated using the direct method (2000 world standard population) and joinpoint regression models were used to fit trend lines. Results Significantly decreasing trends for melanomas on the trunk and upper limbs/shoulders were observed during recent years for both sexes under the age of 40 years and among males aged 40-59 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 on less frequently exposed body sites. These results may provide some indirect evidence of the impact of long-running primary prevention campaigns. [ABSTRACT FROM AUTHOR]