Keratinocyte carcinomas, area-level socioeconomic status and geographic remoteness in Tasmania: cross-sectional associations and temporal trends.

OBJECTIVE: This article aims to examine cross-sectional associations and assess temporal trends in keratinocyte carcinoma (KC) incidence by area-level socioeconomic status (SES) and geographic remoteness in Tasmania, Australia. METHODS: KCs - basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (SCC) - registered by the Tasmanian Cancer Registry were assigned to area-level SES and remoteness area. Incidence rate ratios (2014-2018) were estimated using Poisson regression. Average annual percentage changes (2001-2018) were estimated using the Joinpoint Regression Program. RESULTS: BCC incidence increased with increasing area-level advantage (p-value for trend <0.001), but no trend was found for SCC. SCC incidence was higher in rural than urban areas (p-value <0.001), and BCC incidence was slightly higher in rural than urban areas for females (p-value = 0.009), but not for males (p-value = 0.373). BCC and SCC incidence increased between 2001 and the mid-2010s, when it peaked across most areas. CONCLUSIONS: Associations were found between BCC and higher area-level SES, and between SCC and geographic remoteness. The findings suggest differences in sun exposure behaviours, skin cancer awareness and access to services, or ascertainment bias. IMPLICATIONS FOR PUBLIC HEALTH: Efforts to control and deliver KC services in Tasmania should consider targeting populations with specific area-level characteristics.

International patterns and trends in the incidence of melanoma and cutaneous squamous cell carcinoma, 1989-2020.

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) and melanoma have different associations with sun exposure. OBJECTIVES: To compare trends in the incidence rates of cSCC and melanoma, to provide insight into changing patterns of exposure to ultraviolet radiation (UVR). METHODS: We compared trends in the incidence of cSCC and melanoma in seven susceptible populations residing at mid-to-high latitudes: Finland, Norway, Sweden, Denmark, Scotland, the Netherlands and Tasmania (Australia). We fitted Joinpoint models to describe trends in age-standardized incidence rates for melanoma and cSCC and calculated the average annual percentage rate of change for the period 1989-2020 (1989-2018 for Tasmania). We calculated the incident rate ratio (IRR) as the ratio of the age-standardized rates (European Standard Population) for cSCC to melanoma and conducted age-period-cohort modelling to compare age, period and cohort effects. RESULTS: The ratio of cSCC-to-melanoma incidence increased with proximity to the equator and over time. In the most recent time period, the incidence of cSCC was higher than the incidence of melanoma for men and women in all seven populations. While the ratio of cSCC-to-melanoma incidence was higher for men vs. women, in most countries the cSCC-to-melanoma IRR increased over time to a greater extent in women than in men. Melanoma incidence was higher among younger people and cSCC incidence was higher among older people; the age at which the incidence of cSCC overtook the incidence of melanoma was progressively younger with proximity to the equator. CONCLUSIONS: Despite concerted international efforts to preserve the ozone layer over the past four decades resulting in significant reductions in surface ultraviolet B at mid-latitudes, the incidence of skin cancer, particularly cSCC, continues to rise in those regions. Our findings are consistent with a stronger association with age-associated cumulative sun exposure for cSCC vs. melanoma and suggest that women are currently receiving greater UV radiation exposure than in the past.

Keratinocyte carcinomas, area-level socioeconomic status and geographic remoteness in Tasmania: cross-sectional associations and temporal trends.

OBJECTIVE: This article aims to examine cross-sectional associations and assess temporal trends in keratinocyte carcinoma (KC) incidence by area-level socioeconomic status (SES) and geographic remoteness in Tasmania, Australia. METHODS: KCs-basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (SCC)-registered by the Tasmanian Cancer Registry were assigned to area-level SES and remoteness area. Incidence rate ratios (2014-2018) were estimated using Poisson regression. Average annual percentage changes (2001-2018) were estimated using the Joinpoint Regression Program. RESULTS: BCC incidence increased with increasing area-level advantage (p value for trend <0.001), but no trend was found for SCC. SCC incidence was higher in rural than urban areas (p value <0.001), and BCC incidence was slightly lower in rural than urban areas for males (p value = 0.026), but not for females (p value = 0.381). BCC and SCC incidence increased between 2001 and the mid-2010s, when it peaked across most areas. CONCLUSIONS: Associations were found between BCC and higher area-level SES, and between SCC and geographic remoteness. The findings suggest differences in sun exposure behaviours, skin cancer awareness and access to services, or ascertainment bias. IMPLICATIONS FOR PUBLIC HEALTH: Efforts to control and deliver KC services in Tasmania should consider targeting populations with specific area-level characteristics.

Risk of subsequent keratinocyte carcinomas after a first diagnosis in Tasmania, Australia.

BACKGROUND/OBJECTIVE: A history of keratinocyte carcinoma (KC) is a risk factor for further KCs, but population-based studies quantifying the risk are lacking in Australia. We aimed to describe the risk of subsequent KCs after first KCs in the Australian state of Tasmania. METHODS: Tasmanian residents identified in the Tasmanian Cancer Registry with a first histologically confirmed basal cell carcinoma (BCC), squamous cell carcinoma (SCC) or synchronous BCC and SCC (within 3 months) between January 1985 and December 2013 were followed up for at least 5 years for the development of a subsequent KC. Cumulative risk, incidence rates and standardised incidence ratios (SIRs) were calculated. RESULTS: Those first diagnosed with BCC-only, SCC-only or synchronous BCC and SCC had (i) 5-year cumulative risks of subsequent KCs of 32%, 29% and 51%, (ii) annualised 5-year incidence rates of 8100/100,000 person-years at risk (PYR), 7747/100,000 PYR and 16,634/100,000 PYR and (iii) SIRs of 10.6 (95% CI: 10.5-10.6), 12.5 (95% CI: 12.4-12.6) and 313.0 (95% CI: 305.2-321.1), respectively. Risk estimates increased substantially when multiple (two or more) lesions of any type were diagnosed synchronously. CONCLUSIONS: In the first Australian population-based study to describe the risk of subsequent KCs according to histological types, around one in three Tasmanians diagnosed with first KCs were diagnosed with subsequent KCs within 5 years. The risk of subsequent KCs was higher among those with a history of multiple synchronous lesions, especially if they included both BCC and SCC lesions.

Keratinocyte cancer incidence in Australia: a review of population-based incidence trends and estimates of lifetime risk.

OBJECTIVES: To review the most recent population-based estimates of keratinocyte cancer incidence in Australia, to describe the trends over time and to calculate lifetime risk of developing these skin cancers. METHODS: We conducted a literature search of PubMed/MEDLINE from 2001 to August 2021 to identify relevant literature. We defined eligible articles as those reporting population-based studies of adults and excluded studies that reported only on high-risk or paediatric populations, or on incidence of precursor or related lesions. We summarised identified studies qualitatively. We calculated lifetime risk of developing keratinocyte cancer using the methods of Cancer Research UK, adjusting for multiple primaries and the competing risk of death. RESULTS: We identified six eligible studies. In the absence of compulsory notifications of keratinocyte cancer to state and territory cancer registries in Australia, all estimates of national incidence rates of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) have limitations. The most recent population-based estimates of people annually affected for the period 2011-2014 (BCC: 770/100 000 person years; SCC: 271/100 000 person years) represent the lower end of the possible range of incidence rates nationally. Because many people are affected by multiple lesions, the lesion-based incidence estimates are more than double the person-based rates (BCC: 1565/100 000 person years; SCC: 580/100 000 person years). Analyses of temporal trends in treatment rates (excisions, cryotherapy/curettage) show increases over time, most marked for people aged 55 years or older. We estimate that 69% of Australians will have at least one excision for histologically confirmed keratinocyte cancer in their lifetime (60% to age 79 years). CONCLUSION: The available evidence on national incidence rates is out of date and of moderate quality, but indicates very high rates of keratinocyte cancer in Australia. We recommend that population-based cancer registries work towards statutory notification and routine reporting of keratinocyte cancer in Australia.

Is greater public transport use associated with higher levels of physical activity in a regional setting? Findings from a pilot study.

BACKGROUND: Public transport users often accumulate more physical activity than motor vehicle users, but most studies have been conducted in large metropolitan areas with multiple public transport options with limited knowledge of the relationship in regional and rural areas. In a regional city, this pilot study aimed to (1) test the feasibility of preliminary hypotheses to inform future research, (2) test the utility of survey items, and (3) establish stakeholder engagement. METHODS: Data were collected via a cross-sectional online survey of 743 Tasmanian adults. Physical activity outcomes were walking (min/week), total moderate- to vigorous-intensity physical activity (min/week) and attainment of physical activity guidelines (yes/no). Transport variables were frequency of public and private transport use per week. Truncated and log binomial regression examined associations between public/private transport use and physical activity. RESULTS: Neither frequency of public nor private transport use was associated with minutes of walking (public transport: B - 24.4, 95% CI: - 110.7, 61.9; private transport: B - 1.1, 95% CI: - 72.4, 70.1), minutes of total physical activity (public transport: B - 90.8, 95% CI: - 310.0, 128.5; private transport: B 0.4, 95% CI: - 134.0, 134.9) or not meeting physical activity guidelines (public transport: RR 1.02, 95%CI: 0.95, 1.09; private transport: RR 1.02, 95%CI: 0.96, 1.08). CONCLUSIONS: The hypothesis that public transport users would be more physically active than private transport users was not supported in this pilot study. Stakeholders were engaged and involved in various phases of the research including development of research questions, participant recruitment, and interpretation of findings. Further studies using representative samples and refined measures are warranted to confirm or refute findings.

Temporal trends in the incidence rates of keratinocyte carcinomas from 1978 to 2018 in Tasmania, Australia: a population-based study.

OBJECTIVES: We described incidence trends of keratinocyte carcinomas (KCs)-namely basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)-in the Australian state of Tasmania. METHODS: We identified histologically confirmed KCs within the Tasmanian Cancer Registry (TCR) and conducted assessments to ensure data quality. Age-standardised incidence rates were calculated for first (1985-2018) and annual KCs (1978-2018). Average annual percentage changes were computed using Joinpoint regression models. RESULTS: The TCR is a reliable source of KC data. A total of 83,536 people were registered with a KC between 1978 and 2018. Age-standardised incidence rates of first KCs increased on average by 3% per annum for BCCs and 4% per annum for SCCs, reaching 363/100,000 and 249/100,000 in 2018, respectively. Age-standardised incidence rates of annual KCs increased on average by 5% per annum for BCCs and 6% per annum for SCCs, up to 891/100,000 and 514/100,000 in 2018, respectively. This increase was steeper for females than males and highest during the late 1980s and early 1990s. A change in trend around 2014 suggested that incidence rates have started to decline. CONCLUSION: While the incidence of KCs in Tasmania increased substantially over 41 years, rates have recently plateaued and started to decline. The findings may reflect changes in sun exposure behaviours due to awareness campaigns, but high incidence rates in 2018 indicate that KCs still pose a substantial burden to this population.