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Objective: Claims have been made that sun protection may negatively affect vitamin D status, but very few data are available about whether this applies to people in uncontrolled settings. Method: In 1996 we measured 25(OH)-vitamin D concentrations in 1113 adults in Nambour, a subtropical community, who reported their concurrent sun protection behaviours in a skin cancer prevention trial. Estimates were adjusted for time outdoors, vitamin D intake and other factors known to affect vitamin D status. Results: Persons who tended to stay in the shade had lower vitamin D levels than those who never stayed in the shade (62.5 vs. 68.8nmol/L respectively, p=0.01), and this association remained in persons who spent less than 50% (p=0.02) but not in those who spent more than 50% of their time outdoors. Wearing a hat, long sleeves, sunglasses and use of sunscreen or umbrella were not associated with vitamin D status after adjustments, including after stratification by time outdoors. Conclusion: Sun protection behaviour to reduce the risk of skin cancer can be maintained without affecting vitamin D serum status, although consistently seeking shade when spending less than 50% of daytime outdoors is associated with lower vitamin D levels. [Copyright &y& Elsevier]

Importance: With emerging new systemic treatments for metastatic melanoma, early detection of disease recurrence is increasingly important., Objective: To investigate the risk of melanoma recurrence in patients with a localized melanoma at a high risk of metastasis., Design, Setting, and Participants: A total of 1254 patients with newly diagnosed, histologically confirmed tumor category T1b to T4b melanoma in Queensland, Australia, were recruited prospectively between October 1, 2010, and October 1, 2014, for participation in a cohort study. Data analysis was conducted from February 8, 2018, to February 20, 2019. We used Cox proportional hazards regression analysis to examine associations between patient and tumor factors and melanoma recurrence., Exposures: Disease-free survival (DFS) by melanoma tumor category defined by the 7th vs 8th editions of the AJCC Cancer Staging Manual (AJCC 7 vs AJCC 8)., Main Outcomes and Measures: Melanoma recurrences were self-reported through follow-up questionnaires administered every 6 months and confirmed by histologic or imaging findings., Results: Of 1254 patients recruited, 825 individuals (65.8%) agreed to participate. Thirty-six were found to be ineligible after providing consent and a further 89 patients were excluded after reclassifying tumors using AJCC 8, leaving 700 participants with high-risk primary melanoma (mean [SD] age, 62.2 [13.5] years; 410 [58.6%] men). Independent predictors of recurrence were head or neck site of primary tumor, ulceration, thickness, and mitotic rate greater than 3/mm2 (hazard ratio, 2.36; 95% CI, 1.19-4.71). Ninety-four patients (13.4%) developed a recurrence within 2 years of diagnosis: 66 tumors (70.2%) were locoregional, and 28 tumors (29.8%) developed at distant sites. After surgery for locoregional disease, 37 of 64 patients (57.8%) remained disease free at 2 years, 7 patients (10.9%) developed new locoregional recurrence, and 20 patients (31.3%), developed distant disease. Two-year DFS was similar when comparing AJCC 7 and AJCC 8, for T1b (AJCC 7, 253 [93.3% DFS]; AJCC 8, 242 [93.0% DFS]) and T4b (AJCC 7 and AJCC 8, 50 [68.0% DFS] category tumors in both editions. Patients with T2a to T4a tumors who did not have a sentinel lymph node biopsy (SLNB) at diagnosis had lower DFS than patients with the same tumor category and a negative SLNB (T2a: 136 [91.1%; 95% CI, 86.4-95.9] vs 96 [96.9%; 95 % CI, 93.4-100.0]; T4a: 33 [78.8%; 95% CI, 64.8-92.7] vs 6 [83.3; 95% CI, 53.5-100.0])., Conclusions and Relevance: These findings suggest that 13.4% of patients with a high-risk primary melanoma will experience disease recurrence within 2 years. Head or neck location of initial tumor, SLNB positivity, and signs of rapid tumor growth may be associated with primary melanoma recurrence.

Tea consumption has been shown to protect against skin carcinogenesis in laboratory-based studies; however, epidemiological evidence is limited and inconsistent. This prospective study examined the association between black tea consumption and the incidence of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Usual black tea consumption was estimated from food frequency questionnaires completed in 1992, 1994, and 1996 by 1,325 Australian adults. All histologically confirmed skin cancers diagnosed in participants from 1997 to 2007 were recorded. Relative risks (RRs) and 95% confidence intervals (CIs) were assessed using generalized linear models with Poisson and negative binomial distributions and adjusted for confounding factors including skin phenotype and sun exposure. Compared with never drinking black tea, drinking ≥4 cups/day was not associated with BCC (RR = 1.03, 95% CI: 0.70-1.53; P-trend = 0.74) or SCC (RR = 1.25, 95% CI: 0.71-2.19; P-trend = 0.29) in person-based analyses. Stratification by previous history of skin cancer as well as tumor-based analyses also showed no significant associations between black tea intake and incidence of BCC or SCC tumors. Our results do not support the hypothesis that high black tea consumption reduces risk of skin cancer, including in people with a previous history of skin cancer.

Although sun exposure is known to be associated with basal cell carcinoma (BCC), it is not known what determines multiple occurrences of BCCs among sporadically affected individuals or why BCCs develop on uncommonly sun-exposed body sites like the trunk. In a prospective community-based skin cancer study in Queensland, Australia, we studied all participants who experienced a histologically confirmed BCC from 1992 to 2007. Sun exposure history was monitored, and dermatologists documented phenotype at baseline and signs of photodamage over the study period. Anatomic sites of all incident BCCs were recorded. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using logistic regression. Of 401 participants who developed a new BCC during the 16 years of follow-up, 232 (58%) developed more than 1. Male sex (OR = 2.5, 95% CI 1.5-5.3) and age 60 or over (OR = 4.2, 95% CI 1.5-11.8) but not skin type were associated with highest BCC counts among those affected. Participants with high numbers of solar keratoses were most likely to experience the highest BCC counts overall (OR = 4.3, 95% CI 1.4-13.5). Moreover, occurrences of BCC on the trunk (OR = 3.3, 95% CI 1.4-7.6) and on the limbs (OR = 3.7, 95% CI 2.0-7.0) were strongly associated with high numbers of solar keratoses on these sites, respectively. Among those newly affected by BCC, chronic cutaneous sun damage predicts those who will be affected by more than 1 BCC, while chronic sun damage on the trunk and limbs predicts BCC occurrence on the trunk and limbs, respectively.

Objectives: Ecological studies support the hypothesis that there is an association between vitamin D and pancreatic cancer (PaCa) mortality, but observational studies are somewhat conflicting. We sought to contribute further data to this issue by analyzing the differences in PaCa mortality across the eastern states of Australia and investigating if there is a role of vitamin D-effective ultraviolet radiation (DUVR), which is related to latitude., Methods: Mortality data from 1968 to 2005 were sourced from the Australian General Record of Incidence and Mortality books. Negative binomial models were fitted to calculate the association between state and PaCa mortality. Clear sky monthly DUVR in each capital city was also modeled., Results: Mortality from PaCa was 10% higher in southern states than in Queensland, with those in Victoria recording the highest mortality risk (relative risk, 1.13; 95% confidence interval, 1.09-1.17). We found a highly significant association between DUVR and PaCa mortality, with an estimated 1.5% decrease in the risk per 10-kJ/m increase in yearly DUVR., Conclusions: These data show an association between latitude, DUVR, and PaCa mortality. Although this study cannot be used to infer causality, it supports the need for further investigations of a possible role of vitamin D in PaCa etiology.

A proportion of individuals are affected multiple times by basal cell carcinoma (BCC), but the rate and extent to which this occurs is unknown. We therefore prospectively estimated BCC incidence in a subtropical Australian population, focusing on the rate at which persons develop multiple primary BCCs and the precise anatomic sites of BCC occurrence. Between 1997 and 2006, 663 BCCs were confirmed in 301 of 1,337 participants in the population-based Nambour Skin Cancer Study. The incidence of persons affected multiple times by primary BCC was 705 per 100,000 person years compared to an incidence rate of people singly affected of 935 per 100,000 person years. Among the multiply and singly affected alike, site-specific BCC incidence rates were far highest on facial subsites, followed by upper limbs, trunk, and then lower limbs. We conclude that actual BCC tumor burden is much greater in the population than is apparent from normal incidence rates. Anatomic distribution of BCC is consistent with general levels of sun exposure across body sites.

To investigate the associations between intake of antioxidant nutrients and risk of basal cell (BCC) and squamous cell carcinomas (SCC) of the skin, we carried out a prospective study among 1001 randomly selected adults living in an Australian community. Intake of antioxidants was estimated in 1996. Incident, histologically-confirmed BCC and SCC were recorded between 1996 and 2004. High dietary intake of lutein and zeaxanthin was associated with a reduced incidence of SCC in persons who had a history of skin cancer at baseline (highest versus lowest tertile, multivariable adjusted relative risk (RR)=0.47, 95% confidence interval (CI): 0.25-0.89; P for trend=0.02). In persons without a history of skin cancer at baseline, development of BCC was positively associated with intake of vitamins C and E from foods plus supplements (RR=3.1, 95% CI: 1.1-8.6; P for trend=0.03 and RR=2.6, 95% CI: 1.1-6.3; P for trend=0.02, respectively). In those with a skin cancer history at baseline, dietary intake in the second tertile for beta-carotene (multivariable adjusted RR=2.2, 95% CI: 1.2-4.1) and for vitamin E (multivariable adjusted RR=2.1, 95% CI: 1.1-3.9) was associated with increased BCC risk, with no trend, and similar results were seen in those with a specific history of BCC. These data suggest quite different associations between antioxidant intake and SCC compared with BCC, consistent with other evidence of their different causal pathways.

Background: The role of diet in the development of skin cancer is inconclusive, and the effect of the combined consumption of foods has never been reported., Objective: We prospectively investigated the association between dietary patterns and cutaneous basal cell (BCC) and squamous cell (SCC) carcinoma., Design: Principal components analysis of 38 food groups was used to identify dietary patterns in 1360 adults aged 25-75 y who participated in a community-based skin cancer study in Nambour, Australia, between 1992 and 2002. We obtained baseline information about diet, skin color, and sun exposure factors. Multivariate-adjusted relative risks (RRs) for BCC and SCC tumors were estimated by using negative binomial regression modeling., Results: Two major dietary patterns were identified: a meat and fat pattern and a vegetable and fruit pattern. The meat and fat pattern was positively associated with development of SCC tumors (RR=1.83; 95% CI: 1.00, 3.37; P for trend=0.05) after adjustment for confounders and even more strongly associated in participants with a skin cancer history (RR=3.77; 95% CI: 1.65, 8.63; P for trend = 0.002) when the third and first tertiles were compared. A higher consumption of the vegetable and fruit dietary pattern appeared to decrease SCC tumor risk by 54% (P for trend = 0.02), but this protective effect was mostly explained by the association with green leafy vegetables. There was no association between the dietary patterns and BCC tumors., Conclusion: A dietary pattern characterized by high meat and fat intakes increases SCC tumor risk, particularly in persons with a skin cancer history.

There is some evidence that dietary factors may modify the risk of squamous cell carcinoma (SCC) of the skin, but the association between food intake and SCC has not been evaluated prospectively. We examined the association between food intake and SCC incidence among 1,056 randomly selected adults living in an Australian sub-tropical community. Measurement-error corrected estimates of intake in 15 food groups were defined from a validated food frequency questionnaire in 1992. Associations with SCC risk were assessed using Poisson and negative binomial regression to the persons affected and tumour counts, respectively, based on incident, histologically confirmed tumours occurring between 1992 and 2002. After multivariable adjustment, none of the food groups was significantly associated with SCC risk. Stratified analysis in participants with a past history of skin cancer showed a decreased risk of SCC tumours for high intakes of green leafy vegetables (RR = 0.45, 95% CI = 0.22-0.91; p for trend = 0.02) and an increased risk for high intake of unmodified dairy products (RR = 2.53, 95% CI: 1.15-5.54; p for trend = 0.03). Food intake was not associated with SCC risk in persons who had no past history of skin cancer. These findings suggest that consumption of green leafy vegetables may help prevent development of subsequent SCCs of the skin among people with previous skin cancer and that consumption of unmodified dairy products, such as whole milk, cheese and yoghurt, may increase SCC risk in susceptible persons., (Copyright 2006 Wiley-Liss, Inc.)

The p53 gene is a tumor suppressor gene that is commonly mutated in skin cancer and sun-exposed skin, and this can be detected through immunohistochemical expression of the p53 protein. The authors hypothesized that time spent outdoors is associated with p53 protein expression in human skin and that sunscreen use counteracts the association. In 1996, they investigated this in a community-based cross-sectional study in Australia. Detailed information about skin type, time spent outdoors, and sunscreen use was collected from 139 residents of a subtropical township who also provided a skin biopsy from the back of the hand for measurement of p53 expression. Increasing time spent outdoors was positively associated with immunoreactivity in the whole epidermis and in the basal layer of the epidermis. After adjustment for confounders, p53 immunoreactivity was twice as high for people who used sunscreen 1 or 2 days per week as for those who used sunscreen daily (whole epidermis: ratio estimate=2.0, 95% confidence interval: 1.1, 3.6; basal layer: ratio estimate=1.7, 95% confidence interval: 0.9, 3.1). The authors conclude that p53 immunoreactivity in the skin is a marker of exposure to ultraviolet light in the past 6 months, but this may be mitigated by regular application of sunscreen.