Skin cancer in a Queensland population

Reduced melanoma after regular sunscreen use: randomized trial follow-up

PURPOSE

Regular sunscreen use prevents cutaneous squamous cell carcinoma long term, but the effect on melanoma is highly controversial. We evaluated whether long-term application of sunscreen decreases risk of cutaneous melanoma.

PARTICIPANTS AND METHODS

In 1992, 1,621 randomly selected residents of Nambour, a township in Queensland, Australia, age 25 to 75 years, were randomly assigned to daily or discretionary sunscreen application to head and arms in combination with 30 mg beta carotene or placebo supplements until 1996. Participants were observed until 2006 with questionnaires and/or through pathology laboratories and the cancer registry to ascertain primary melanoma occurrence.

RESULTS

Ten years after trial cessation, 11 new primary melanomas had been identified in the daily sunscreen group, and 22 had been identified in the discretionary group, which represented a reduction of the observed rate in those randomly assigned to daily sunscreen use (hazard ratio [HR], 0.50; 95% CI, 0.24 to 1.02; P = .051). The reduction in invasive melanomas was substantial (n = 3 in active v 11 in control group; HR, 0.27; 95% CI, 0.08 to 0.97) compared with that for preinvasive melanomas (HR, 0.73; 95% CI, 0.29 to 1.81).

CONCLUSION

Melanoma may be preventable by regular sunscreen use in adults.

Orbital metastasis: clinical features, management and outcome

PURPOSE

To review the clinical features, treatment, outcome and survival of metastatic tumors of the orbit.

MATERIALS AND METHODS

Retrospective, non-comparative, chart review of 80 patients with orbital metastasis treated in four tertiary orbital centres in Australia.

RESULTS

The study included 80 patients of which, 44 were male with a mean age of 60 years. Orbital involvement commonly presented late in a multisystemic disease; however, the orbit was the first presentation in 15% of the cases. Diplopia (48%), pain (42%), and visual loss (30%) were the commonest symptoms at presentation; whereas proptosis (63%), strabismus (62%), and visual loss (41%) were the most frequent clinical signs. Computed tomography commonly showed a solid enhancing mass (42 cases) located within the orbital fat (43%), or enlarging an extraocular muscle (28%). Breast carcinoma (29%), melanoma (20%), and prostatic cancer (13%) were the most frequent histological types. Treatment was often multi-disciplinary and modalities included radiotherapy, chemotherapy, hormone therapy, surgery, and immunotherapy. Survival was limited to 1.5 years after diagnosis independent of the histological type, with 29% of patients alive after 17 months follow-up.

CONCLUSIONS

A high index of suspicion and appropriate intervention with histological diagnosis can help in the management and quality of life in patients with metastatic orbital disease. Overall survival is limited and we encountered statistical limitations proving differences in the survival based on the sub-type of primary tumour involved. Metastatic orbital melanoma presented a higher incidence when compared with previous studies, probably due to the increase frequency of skin found in the Australian population.

Professional risk for skin cancer development in male mountain guides--a cross-sectional study

OBJECTIVE

For reasons of their outdoor work, mountain guides (MG) are heavily exposed to ultraviolet radiation during their work.

METHODS

A standardized interview and examination were performed on 283 male MG (median 41 years) from Germany, Switzerland and Austria and 309 age-matched controls. The median occupation time as MG was 17 years; 39.9% were working full-time.

RESULTS

The incidence of skin cancer and precancerous lesions was obtained. Precancerous lesions as solar keratosis (SK) were significantly more frequent in MG (25.4% vs. 7.4%). There was no skin cancer [BCC, SSC, melanoma (MEL)] in the control subjects. Basal cell carcinoma (BCC) was diagnosed in 20 MG (7.1%) and SSC in four MG (1.4%). There were 10 highly suspicious melanocytic lesions; one MG had a histologically confirmed malignant MEL. Risk factors for SK in the multivariate analysis included occupation (P < 0.0001), age (P < 0.0001) and skin type (P = 0.0002). Within the MG group, age (P < 0.0001) and hair colour (P = 0.0058) were independent risk factors for SK. Severe lifetime sunburns (P = 0.0007) and skin type (P = 0.041) were the significant risk factors for BCC, within the MG group in addition to the number of guiding days (P = 0.010). The risk factor for skin cancer (BCC, SCC and MEL) was the number of heavy sunburns during lifetime (P = 0.0014).

CONCLUSION

The present study demonstrates an association between high occupational ultraviolet-exposure and an increased prevalence of precancerous skin lesions and skin cancer. MG may be considered as an example for other outdoor professionals. Skin cancer of outdoor workers is likely to be an occupational disease. Primary and secondary prevention should be enforced.

Malignant skin neoplasms

Skin cancers may be derived from any part of the skin, and the classification of all variants is extensive. Overall they are the most common cancers of the body, and include those that are highly mortal and those that are associated with an increased morbidity. In this review the most common skin cancers confronted by the clinician and their management are discussed. New associations are highlighted, as well as new information that can help the clinician to better understand the pathogenesis of many of these entities.

Dietary fat intake and risk of skin cancer: a prospective study in Australian adults

Although intakes of dietary fat have been associated with both basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) of the skin, the evidence is sparse and inconsistent. This study prospectively investigated the association between total dietary fat; saturated, polyunsaturated and monounsaturated fatty acids; and percent energy from fat in relation to BCC and SCC of the skin. At baseline in 1992, total fat intake and intake of fatty acids were assessed in an Australian community-based longitudinal study, using a validated semi-quantitative food frequency questionnaire in 1,057 adult residents (aged 25-75 years) in Nambour, Queensland. Information on demography, sun-sensitivity history and sun exposure factors were obtained using self-administered questionnaires. Associations with BCC and SCC in terms of persons newly affected and of tumor counts were assessed using Poisson and negative binomial regression models, respectively, based on incident, histologically-confirmed tumors occurring between 1992 and 2002. No significant linear trends were observed in overall risk of BCC or SCC of the skin with increasing total fat intake. However, in participants with a history of skin cancer, total fat intake (multivariable adjusted RR = 2.42, 95% CI = 1.20-4.88; p for trend = 0.01) was associated with increased numbers of SCC tumors comparing the highest to lowest tertile. In conclusion, SCC tumor risk increased as total fat intake increased in people with a history of skin cancer. Dietary fats were not associated with BCC occurrence.

Polymorphisms in the syntaxin 17 gene are not associated with human cutaneous malignant melanoma

The prevalence of cutaneous malignant melanoma (CMM) has increased significantly in most Caucasian populations in recent decades. Both genetic and environmental risk factors are involved in the development of CMM. A germline mutation in the syntaxin 17 (STX17) gene of horses was recently identified, which causes premature hair graying and is associated with susceptibility to melanoma. We hypothesized that common germline variants in the STX17 gene might be associated with a predisposition to human CMM or might interact with other melanoma risk genes. We genotyped 26 tagging single nucleotide polymorphisms (SNPs) across the STX17 gene region in an Australian sample of 1560 melanoma cases and 1650 controls and performed logistic regression analysis to identify potential SNP interactions in a combined dataset. Our results do not support an association between CMM and any of the STX17 SNPs and provide no evidence for interactions between the melanoma risk SNP rs910873 on chromosome 20 and any of the STX17 SNPs. We conclude that common variants in the STX17 gene region do not play a key role in the pathogenesis of human melanoma.

Serum antioxidants and skin cancer risk: an 8-year community-based follow-up study

BACKGROUND

Antioxidant nutrients can help prevent skin damage caused by ultraviolet radiation from sunlight, but it is not clear whether serum concentrations of such nutrients influence skin cancer risk.

METHODS

We carried out a prospective study of the associations between serum concentrations of antioxidant nutrients and incidence (person-based and tumor-based) of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) of the skin among a random subsample of 485 adults from an Australian community. Participants were divided into thirds, ranked according to their serum concentrations of carotenoids, alpha-tocopherol, and selenium measured in 1996 and were monitored for incident, histologically confirmed BCC and SCC tumors until 2004.

RESULTS

Although there were no associations between baseline serum carotenoids or alpha-tocopherol concentrations and incidence of BCC or SCC, baseline serum selenium concentrations showed strong inverse associations with both BCC and SCC tumor incidence. Compared with participants with lowest selenium concentrations at baseline (0.4-1.0 micromol/L), those with the highest serum selenium concentrations (1.3-2.8 micromol/L) had a decreased incidence of BCC tumors (multivariate relative risk, 0.43; 95% confidence interval, 0.21-0.86; P(trend) = 0.02) and SCC tumors (multivariate relative risk, 0.36; 95% confidence interval, 0.15-0.82; P(trend) = 0.02).

CONCLUSION

Relatively high serum selenium concentrations are associated with an approximately 60% decrease in subsequent tumor incidence of both BCC and SCC, whereas serum concentrations of carotenoids or alpha-tocopherol are not associated with later skin cancer incidence. A possible U-shaped association between serum selenium concentrations and SCC of the skin needs confirmation.

Pharmacoeconomic considerations in treating actinic keratosis

Actinic keratosis is among the most commonly treated skin conditions in the outpatient setting. Its prevalence spans the globe, with greater distribution in fair skinned individuals and the immunocompromised. With high prevalence, increasing incidence and the risk of transformation to a cancerous lesion, prevention and timely treatment present opportunities to rein in costs. The purpose of this article is to review published economic studies relating to the treatment of actinic keratosis, to summarize results discussing the cost drivers of current treatment modalities and to identify parameters most likely to influence the cost effectiveness of treatment. We systematically conducted a published literature search for pharmacoeconomic research of actinic keratosis using title, abstract or full-text searches with the following search terms ([actinic OR solar] AND [keratosis OR keratoses]) AND (economic OR cost OR pharmacoeconomics OR decision). We included published articles referencing actinic keratosis in a standalone study or in a broader study referencing non-melanoma skin cancer and articles evaluating cost-of-illness, cost-of-treatment, cost minimization, cost effectiveness, cost utility, cost-benefit analysis and cost consequence. Our review of the literature found nine studies devoted to pharmacoeconomic considerations of actinic keratosis treatments, with one article investigating both cost-of-illness and cost-of-treatment, two measuring cost-of-illness, two evaluating cost-of-treatment, one focusing on cost minimization, and three focusing on cost effectiveness. The literature compared a broad range of actinic keratosis treatments including topical medications, cryotherapy, photodynamic therapy, excision and a combination of treatment modalities. The direct cost of actinic keratosis management in the US was estimated at $US1.2 billion per year, with indirect costs totalling $US295 million (year 2004 values). The primary drivers of cost were physician office visits and associated procedures. Pharmacoeconomic research defining standards, outcomes and areas of efficiencies in the treatment of actinic keratosis is in its infancy. To move towards more comprehensive analysis, research needs to focus on updating epidemiological data, evolving evidence-based standards, delineating cost drivers in immunocompetent and immunocompromised populations, and on health outcomes.

Incidence of basal cell carcinoma multiplicity and detailed anatomic distribution: longitudinal study of an Australian population

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.

Intake of antioxidant nutrients and the risk of skin cancer

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.

Solar keratosis: epidemiology, pathogenesis, presentation and treatment

Solar keratosis is a common problem encountered by dermatologists, particularly in Australia. Solar keratosis is most commonly found on sun-exposed areas such as the scalp, face and forearms. UV radiation is thought to be the major aetiological factor, with age, immunosuppression and human papillomavirus being important contributing factors. Solar keratosis usually presents as a discrete, variably erythematous and irregular lesion with a scaly surface. Although the exact rate of malignant transformation to squamous cell carcinoma is unknown, the majority of squamous cell carcinomas appear to arise from within solar keratosis. For this reason, solar keratosis is commonly treated and, consequently, an increasing number of therapeutic options is now available. Traditional therapies, such as liquid nitrogen cryotherapy, are still popular, but newer choices, such as photodynamic therapy and imiquimod cream, are now providing further options with similar efficacy and superior adverse effect profiles, albeit at a higher cost.

Dietary pattern in association with squamous cell carcinoma of the skin: a prospective study

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.

Validation of a FFQ to estimate the intake of PUFA using plasma phospholipid fatty acids and weighed foods records

Due to the growing knowledge about the role of specific fatty acids in health and disease, dietary intake measurements of individual fatty acids or classes of fatty acids are becoming increasingly important. The objective of this study was to evaluate the ability of the Nambour FFQ to estimate intakes of specific fatty acids, particularly PUFA. The study population was a sub-sample of adult participants in a randomised controlled trial of beta-carotene and sunscreen in the prevention of skin cancer (n 43). Dietary intake was assessed by a self-administered FFQ and a weighed food record (WFR). Non-fasting blood samples were collected and analysed for plasma phospholipid fatty acids. Median intakes on the FFQ were generally higher than the WFR except for the n-3 PUFA groups, where the FFQ estimated higher intakes. Correlations between the FFQ and WFR were moderate (r 0 x 32-0 x 59) except for trans fatty acids (r 0 x 03). Correlations between each of the dietary assessment methods and the plasma phospholipids were poor for all fatty acids other than the PUFA. Using the methods of triads approach, the FFQ validity coefficients for total n-3 fatty acids, total long chain n-3 fatty acids, EPA, arachidonic acid, docosapentaenoic acid and DHA were 0 x 50, 0 x 63, 0 x 45 and 0 x 62 and 0 x 62, respectively. For most fatty acids, the FFQ adequately estimates group mean fatty acid intakes and can adequately rank individuals; however, the ability of this FFQ to estimate trans fatty acids was poor.

Trends in incidence of skin basal cell carcinoma. Additional evidence from a UK primary care database study

We determined the trends in incidence of skin basal cell carcinoma (BCC) using a primary care population-based cohort study in the UK. 11,113 adults with a BCC diagnosis were identified from a total of 7.22 million person-years of data between 1996 and 2003 from the Health Improvement Network database. From a random subsample of BCC cases identified from the database, 93% were confirmed by hospital letter and/or pathology report. The incidence of BCC was 153.9 per 100,000 person-years (95% CI 151.1, 156.8) and was slightly higher in men as compared to women (Incidence Rate Ratio 1.10, 95% CI 1.06, 1.14). There was a 3% increase year on year across the study period (IRR 1.03, 95% CI 1.01, 1.04), with the largest increase in incidence seen in the 30-39 year age groups, although this did not reach statistical significance. Our study indicates 53,000 new cases of BCC are estimated every year in the UK and figures are continuing to rise on a yearly basis. Incidence rates are highest for men and in particular in the older age categories. These findings are consistent with those reported for various other populations. We have also found an increase in incidence in ages 30-39, which may suggest a cohort effect of increasing ultraviolet exposure in successive younger generations. This may have a huge public and service impact in future years in countries such as the UK, with predominantly fair-skinned population, with high leisure exposure to ultraviolet light. Our findings underline the need for more elaborate preventive measures.

Occupational exposure to ultraviolet radiation: the duality dilemma

Human exposure to ultraviolet (UV) radiation is a component of everyday life and a significant hazard for outdoor workers. In addition, a large range of artificial sources also has the potential to provide extreme occupational UV exposure. Even though the human health risks of overexposure to UV are well documented, to date relatively little is known quantitatively about UV exposure. For example, the evidence indicates that workers who are exposed to particular sources (for example, welding arcs) are exposed to extreme UV exposures, despite the use of current control measures. In contrast, increasing evidence points to significant health impacts resulting from underexposure to UV, particularly with the production (or more correctly lack of production) of vitamin D in the skin. The latter poses a serious issue for the work-force, with specific risks for workers lacking adequate sun exposure-underground miners, long-haul flight crews, shift workers, and perhaps indoor workers. Using a risk-management approach, this paper provides a comprehensive review of occupational UV sources, health impact of occupational UV exposure, occupational exposure standards, and levels of exposure in various settings, and discusses the appropriate control measures. In addition, the duality aspect of health impacts from overexposure and underexposure to UV and the associated occupational health implications are specifically explored.

Clinical and pathological study of lichen-planus-like keratosis in China

Lichen-planus-like keratosis is usually diagnosed pathologically; rarely, a definitive diagnosis can be made grossly in the clinic. Only a few cases of lichen-planus-like keratosis have been reported in China. The purpose of this study was to investigate the clinical and pathological features of lichen-planus-like keratosis in China. Fifty cases of lichen-planus-like keratosis patients diagnosed pathologically during a 5-year period in our clinic were analyzed. Clinical features were recorded. Sectioned specimens were subjected to hematoxylin and eosin staining to observe pathological changes. Results showed that there were 34 males and 16 females (ratio 2:1) with an average age of 61.2 years. Most of the lesions were single papules or plaques with rough surfaces. They were distributed on the face, larger than 1 cm, and dark red to brown in color. Only one case (2%) was considered to be lichen-planus-like keratosis clinically. By hematoxylin and eosin staining, solar lentigo and solar elastosis could be found in 68% and 32% of lichen-planus-like keratosis lesions, respectively. Eosinophil (42%) and plasma cell (36%) infiltration was also found frequently. Exoerythrocytes could be detected in 50% of the cases. Lichen-planus-like keratosis is not uncommon in clinical practice in China, the diagnosis of lichen-planus-like keratosis should be made by a combination of clinical manifestations and pathological changes. It is better to classify lichen-planus-like keratosis as a benign skin tumor. More attention should be paid to lichen-planus-like keratosis in China.

Anthropometric measures in relation to basal cell carcinoma: a longitudinal study

BACKGROUND

The relationship between anthropometric indices and risk of basal cell carcinoma (BCC) is largely unknown. We aimed to examine the association between anthropometric measures and development of BCC and to demonstrate whether adherence to World Health Organisation guidelines for body mass index, waist circumference, and waist/hip ratio was associated with risk of BCC, independent of sun exposure.

METHODS

Study participants were participants in a community-based skin cancer prevention trial in Nambour, a town in southeast Queensland (latitude 26 degrees S). In 1992, height, weight, and waist and hip circumferences were measured for all 1621 participants and weight was remeasured at the end of the trial in 1996. Prevalence proportion ratios were calculated using a log-binomial model to estimate the risk of BCC prior to or prevalent in 1992, while Poisson regression with robust error variances was used to estimate the relative risk of BCC during the follow-up period.

RESULTS

At baseline, 94 participants had a current BCC, and 202 had a history of BCC. During the 5-year follow-up period, 179 participants developed one or more new BCCs. We found no significant association between any of the anthropometric measures or indices and risk of BCC after controlling for potential confounding factors including sun exposure. There was a suggestion that short-term weight gain may increase the risk of developing BCC for women only.

CONCLUSION

Adherence to World Health Organisation guidelines for body mass index, waist circumference and waist/hip ratio is not significantly associated with occurrence of basal cell carcinomas of the skin.

Long-term increase in sunscreen use in an Australian community after a skin cancer prevention trial

BACKGROUND

Given the public health burden of skin cancer in white populations, an increase in sun protective behavior is needed. In a high-risk community, we assessed long-term sunscreen use among people who had participated in a randomized trial of daily sunscreen application for prevention of skin cancer.

METHODS

In 1992, 1621 residents of the subtropical Australian township of Nambour were randomly allocated to either daily or discretionary sunscreen use until 1996. From 1997 to 2002, we monitored by questionnaires their ongoing sunscreen use.

RESULTS

People who had never or irregularly used sunscreen when in summer sun before the trial were more likely (P < 0.0001) to be sustaining regular application especially to their face (20% vs. 11%) and forearms (14% vs. 5%) if they had been allocated to daily, not discretionary, use of sunscreen for 5 years.

CONCLUSIONS

Regular voluntary sunscreen use for skin cancer prevention can be sustained by sun-sensitive people in the long term. Habit formation appears to be an important goal for sun protection programs among those living, or on vacation, in sunny places.

Food intake and risk of squamous cell carcinoma of the skin in a community: The Nambour skin cancer cohort study

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.

Antioxidants and basal cell carcinoma of the skin: a nested case-control study

OBJECTIVE

To investigate the relationship between basal cell carcinoma (BCC) and antioxidant nutrients, specifically carotenoids, vitamin E and selenium.

METHODS

The Nambour Skin Cancer Study is an ongoing, community-based study of randomly selected adult residents of a township in sub-tropical Queensland, Australia. Using a nested case-control design, incident cases of BCC (n=90) were compared with age and sex matched controls (n=90). Dietary exposure was measured using food frequency questionnaire estimates of intake as well as serum biomarkers. Other determinants of skin cancer including sun exposure were also considered. Dietary intakes were adjusted for energy intake, and serum carotenoids and vitamin E were adjusted for serum cholesterol. Odds ratios were calculated across quartiles of dietary intake and serum biomarkers and linear trends were assessed using logistic regression, adjusting for age, sex and supplement use.

RESULTS AND CONCLUSIONS

In this prospective study no significant associations were found between BCC and carotenoids, vitamin E or selenium, as measured by serum biomarkers or dietary intake, although there was a suggestion of a positive association with lutein intake.

Nonsteroidal anti-inflammatory drugs and the risk of actinic keratoses and squamous cell cancers of the skin

BACKGROUND

Although animal studies suggest that nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin, may protect against cutaneous squamous cell carcinoma (SCC) and actinic keratoses (AKs), possible effects on keratinocytic cancers in humans are unknown.

OBJECTIVE

We sought to examine the relationship between ingestion of NSAIDs and the risk of SCC and AKs in humans.

METHODS

We conducted a case-control study nested within a community-based cohort of 1621 people in southern Queensland, Australia. Eighty-six persons with SCC were compared with 187 age- and sex-matched control subjects randomly selected from within the cohort. NSAID use was captured through face-to-face interviews with study participants, supplemented by color photographs of product packaging. We defined regular use of NSAIDs as consumption of at least two tablets per week (low frequency) or at least 8 tablets per week (high frequency) for at least 1 year. AKs were counted on the face, ears, right hand, and right forearm by a single physician.

RESULTS

Patients with SCC were significantly less likely than control subjects to have used any NSAIDs 8 or more times per week for more than 1 year (multivariate odds ratio [OR] 0.07, 95% confidence interval [CI] 0.01-0.71) and to have used full-dose NSAIDs 2 or more times per week for more than 5 years (OR, 0.20; 95% CI, 0.04-0. 96). Among participants without SCC, current regular users of NSAIDs (> or =2 times per week) had significantly lower counts of AKs than nonusers (rate ratio [RR], 0.52; 95% CI, 0.30-0.91).

LIMITATIONS

Estimates of NSAID use were based on self-reported data. Statistical power to detect associations was limited by the number of cases with SCC.

CONCLUSION

Regular users of NSAIDs appear to have lower risks of SCC and lower counts of AKs than nonusers.

Non-melanoma skin cancer in Catalonia. A community-based prevalence study

INTRODUCTION

Accurate epidemiologic studies of non-melanoma skin cancer in South Europe are nearly absent. Incidence studies based on treated cases are difficult and may overlook asymptomatic tumors. Studying cohorts of populations in order to establish prevalence data are necessary to give realistic impressions of the problem.

MATERIALS AND METHODS

A population-based cohort of 1000 women was examined for skin cancer. The sample was obtained from women attending a massive campaign of mammography addressing all women aged 50-65 years in the area of Sant Boi de Llobregat, Catalonia, Spain. Examination included full body areas, except those covered by underwear or hair, and feet.

RESULTS

Nine cases of basal cell carcinoma were histologically confirmed, resulting in a prevalence of 900 cases in 10(5) (95% CI 601; 1198). Five of them were located on the trunk, in non-exposed sites.

CONCLUSION

The prevalence of basal cell carcinoma found in our population is one of the highest reported in Europe. A significant proportion of tumors are on the trunk, suggesting the existence of a high proportion of undetected cases. Similar studies in 5-10-year intervals could aid detection of changing trends in the prevalence of skin cancer in our population.

Role of dietary factors in the development of basal cell cancer and squamous cell cancer of the skin

The role of dietary factors in the development of skin cancer has been investigated for many years; however, the results of epidemiologic studies have not been systematically reviewed. This article reviews human studies of basal cell cancer (BCC) and squamous cell cancer (SCC) and includes all studies identified in the published scientific literature investigating dietary exposure to fats, retinol, carotenoids, vitamin E, vitamin C, and selenium. A total of 26 studies were critically reviewed according to study design and quality of the epidemiologic evidence. Overall, the evidence suggests a positive relationship between fat intake and BCC and SCC, an inconsistent association for retinol, and little relation between beta-carotene and BCC or SCC development. There is insufficient evidence on which to make a judgment about an association of other carotenoids with skin cancer. The evidence for associations between vitamin E, vitamin C, and selenium and both BCC and SCC is weak. Many of the existing studies contain limitations, however, and further well-designed and implemented studies are required to clarify the role of diet in skin cancer. Additionally, the role of other dietary factors, such as flavonoids and other polyphenols, which have been implicated in skin cancer development in animal models, needs to be investigated.

Merkel cell carcinoma: improved outcome with adjuvant radiotherapy

BACKGROUND

Merkel cell carcinoma is an aggressive primary cutaneous neuroendocrine carcinoma. Patients remain at high risk of locoregional and distant relapse despite treatment. Most studies support the incorporation of locoregional adjuvant radiotherapy in reducing the risk of relapse.

METHODS

Between 1980 and 2002, 86 patients diagnosed with Merkel cell carcinoma were treated with curative intent at Westmead Hospital, Sydney. Multivariate analysis was performed using Cox regression analysis. Disease-free survival and overall survival was calculated using Kaplan-Meier survival curves.

RESULTS

Median age at diagnosis was 75 years (range 46-89 years) in 49 men and 37 women. Median duration of follow up was 31 months (range 6-153 months). Fifty-one (59%) patients presented with a primary lesion, 19 (22%) with a primary lesion and clinical nodal disease and 16 (19%) with lymph node metastases from an unknown primary. A total of 47 of 86 (55%) relapsed with regional nodal relapse, the commonest site of first relapse. Local relapse was similar for patients undergoing surgery (5/37; 14%) compared with surgery and adjuvant radiotherapy (3/25; 12%). Nodal relapse occurred in 14 of 36 (37%) treated with surgery compared with 7 of 38 (18%) patients treated with surgery and adjuvant radiotherapy. Patients treated with surgery and adjuvant radiotherapy experienced a better median disease free survival compared to those undergoing surgery alone (10.5 months vs 4 months; P < 0.01). The 5-year overall and disease-free survival rate for the entire study population was 47% and 25%, respectively. Twenty-six patients (30%) died as a result of Merkel cell carcinoma.

CONCLUSION

Merkel cell carcinoma is an aggressive skin cancer. The addition of adjuvant radiotherapy markedly improves regional control rates and should be considered best practice.

Premalignant and early squamous cell carcinoma

Actinic keratosis (AK) is a common sun-induced precancerous neoplasm confined to the epidermis. The AK is the initial manifestation of a continuum of clinical and histologic abnormalities that progresses to invasive squamous cell carcinoma (SCC). Bowen's disease, also known as squamous cell carcinoma in situ, represents early SCC confined to the epidermis. More than half of all SCCs contain p53 tumor suppressor gene mutations. Like SCCs, the vast majority of AKs and Bowen's disease lesions are asymptomatic. Each AK and suspicious lesion should be treated before it progresses to invasive SCC. Destructive modalities, such as cryosurgery using liquid nitrogen and electrodesiccation and curettage, usually performed by a dermatologist, are the mainstays of therapy.

Basal Cell Carcinomas of the Eyelids

Basal cell carcinomas (BCC) are the more frequent malignant tumors seen in France as in other western countries. They represent 20% of eyelid tumors and 90% of eyelid malignancies. Due to their local growth, problems may arise when treating BCC, and curative exeresis must be the preferred choice each time it is possible. BCC of the eyelids have a high risk of recurrence. Recurrences are more aggressive, infiltrative and destructive and have a considerably poorer rate of cure than primary tumors. Eyelid reconstructions can entail use of complex methods which should only be carried out by a trained ophthalmologist who is also able to treat any associated age-related ocular pathologies. BCC is the most common cause leading to eyelid reconstructive surgery; a surgery which has a triple objective: tumor removal, functionality and an esthetic outcome.

Self-reported dermatitis and skin cancer in California farm operators

BACKGROUND

High rates of skin diseases and higher non-melanoma skin cancer rates have been reported in farmers.

METHODS

Self-report of dermatitis and skin cancer was among the information collected from 1947 California farm operators, mostly men, in a telephone survey. The majority of the farmers cultivated fruits, nuts, or other field crops.

RESULTS

Dermatitis was reported by 8.9% of men and 15.8% of women during the previous 12 months. In a logistic regression model, female gender (OR 2.0, 95% confidence interval 1.3-3.0) and respiratory atopy (OR 1.4, 1.01-1.90) were the only significant independent risk factors for reported dermatosis. There was significantly less reporting of skin cancer among field farmers when compared to others. Regular sunscreen use was reported significantly more often by women (42%) as compared to men (11%).

CONCLUSIONS

More in-depth studies are needed to get information on the role of agrochemicals as risk factors for dermatitis and skin cancer.

The effect of skin examination surveys on the incidence of basal cell carcinoma in a Queensland community sample: a 10-year longitudinal study

Skin cancers pose a significant public health problem in high-risk populations. We have prospectively monitored basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) incidence in a Queensland community over a 10-y period by recording newly treated lesions, supplemented by skin examination surveys. Age-standardized incidence rates of people with new histologically confirmed BCC were 2787 per 100,000 person-years at risk (pyar) among men and 1567 per 100,000 pyar among women, and corresponding tumor rates were 5821 per 100,000 pyar and 2733 per 100,000 pyar, respectively. Incidence rates for men with new SCC were 944 per 100,000 pyar and for women 675 per 100,000 pyar; tumor rates were 1754 per 100,000 pyar and 846 per 100,000 pyar, respectively. Incidence rates of BCC tumors but not SCC tumors varied noticeably according to method of surveillance, with BCC incidence rates based on skin examination surveys around three times higher than background treatment rates. This was mostly due to an increase in diagnosis of new BCC on sites other than the head and neck, arms, and hands associated with skin examination surveys and little to do with advancing the time of diagnosis of BCC on these sites as seen by a return to background rates following the examination surveys. We conclude that BCC that might otherwise go unreported are detected during skin examination surveys and thus that such skin cancer screening can influence the apparent burden of skin cancer.

Role of modern radiotherapy in treating skin cancer

Radiotherapy is an important modality in the treatment of non-melanoma skin cancers. While the majority of patients will be adequately treated without the need for radiotherapy, there are factors that may favour a recommendation for radiotherapy. The established roles of modern radiotherapy include the definitive, adjuvant and palliative settings. It is important that clinicians treating skin cancers have an understanding and awareness of these roles. The aim of this article is to present an overview of radiotherapy in the current Australian setting.

Expression of p53, bcl-2 and growth hormone receptor in actinic keratosis, hypertrophic type

According to novel investigations, actinic keratosis (AK) is not a premalignant lesion but is a malignant lesion in the evolution to invasive squamous cell carcinoma (SCC). Thus, we analyzed p53, bcl-2 and growth hormone receptor (GHR) expression in hypertrophic-type AK (HAK) to determine the relative importance of these protooncogenes in the biological behavior of HAK. Expression of p53, bcl-2 and GHR was determined by immunohistochemistry in 33 HAK specimens and surrounding perilesional normal skin (PNS). The relative proportions of immunoreactive cells were determined. Of the 33 HAK specimens, 30 (91%) showed immunopositive staining for p53, 33 (100%) for bcl-2, and 12 (36%) for GHR. Highly positive p53 expression in HAK lesions could indicate that p53 mutation is an early and crucial event in lesion development. The detected pattern of the p53/ bcl-2 ratio in HAK suggests an important role for another gene: the proapoptotic gene bax. Our findings indicate that GHR expression could be a biological marker of progression of HAK to SCC.

Effect of smoking and sun on the aging skin

Smoking and ultraviolet radiation are known to have a detrimental effect on human skin. Important characteristics of the aging skin are elastosis and telangiectasia. The purpose of the study was to assess the relative importance of age per se, and the detrimental effects caused by sun exposure and smoking on the development of cutaneous elastosis and telangiectasia in a well-defined group of individuals. We made use of 966 individuals who participated in a case-control study to investigate environmental and genetic risk factors for skin cancer. Exposure measurements for sunlight and smoking were collected and the amount of elastosis and telangiectasia in the face and neck was recorded according to a four-graded score varying from none to severe. Relative risks were estimated using exposure odds ratios from cross-tabulation and logistic regression. Multivariate logistic regression was used to adjust for potential confounders. Among both sexes a strong association was observed between increasing age, sun exposure, and amount of elastosis. The association between increasing age, sun exposure, and amount of telangiectasia was strong among men, but less apparent among women. Smoking was also associated with elastosis among both sexes, and with telangiectasia predominantly among men. Intrinsic differences between men and women (e.g., hormones) or behavior differences (e.g., more frequent use of creams and cosmetics among women) could account for this apparent difference in the occurrence of telangiectasia. In contrast to elastosis, telangiectasia may not be a good marker of the aging skin, specifically not in women.

Induction of metallothionein in human skin by routine exposure to sunlight: evidence for a systemic response and enhanced induction at certain body sites

Expression of metallothionein, an antioxidant induced by a variety of stimuli including ultraviolet light, was quantitated by immunohistochemistry in the skin of males aged over 50 who had known short- and long-term exposures to sunlight. Skin punch biopsies were taken from two sites in each subject: the hand in all subjects and a range of other sites matched to patients with a previously excised primary melanoma. Metallothionein expression (strongest in the basal layers of the epidermis and primarily nuclear) was associated with both short- and long-term exposure to sunlight. A plateau of staining intensity was reached after 3 h sun exposure, within the previous 3 d before biopsy. Expression was also elevated in the nonexposed skin sites of subjects who had recent sun exposure, indicating a systemic response to exposure of remote sites. Using the skin of the hand to normalize responses to chronic exposure between individuals, the systemically modulated response to sunlight was significantly greater on the unexposed back than on other sites. The possibility of ultraviolet-induced cytokines selectively modifying the response of skin on a site-specific basis was investigated. The circulating leukocytes, but not lymphocytes, of two individuals exposed to 1 minimal erythema dose whole-body solar-simulated ultraviolet showed increased interleukin-6 mRNA 4 h after exposure. Interleukin-6 was not directly induced in these cell populations 4 h after ultraviolet A or ultraviolet B irradiation ex vivo. Leukocytes may therefore contribute to and amplify the systemic effects of ultraviolet-induced interleukin-6 and metallothionein expression.

Topical diclofenac in hyaluronan gel for the treatment of solar keratoses

This randomized, double-blind, placebo-controlled study assessed the efficacy and safety of a topical gel containing 3% diclofenac in 2.5% hyaluronan in 150 patients with solar keratoses (SK). The active treatment was compared with the vehicle only, hyaluronan gel, as placebo over a 12-week period. Patients in both groups applied the active treatment or placebo to a targeted area of skin (0.25 g b.d.). At 12 weeks the mean lesion-count reduction in the targeted area was not significantly different between treatments. However, at post-termination follow up (16 weeks), there was a highly significant decrease in the number of lesions, 6.2 +/- 7.5 standard deviations (SD) (56.1% reduction) in the active treatment group compared with 2.4 +/- 4.3 SD (23.6% reduction) in the placebo group (P < 0.001). Other efficacy measures (complete lesion resolution, >50% lesion reduction) were also significantly different (P < 0.01) between treatments at 16 weeks. In conclusion, topical 3% diclofenac in 2.5% hyaluronan gel was effective and well tolerated in this study, suggesting a role for this therapy in the treatment of SK.

Solar keratoses: analysis in a dermatological practice in Australia

Two hundred consecutive patients with solar keratoses (SK) seen in a private dermatology practice had on average 61.9 SK compared with eight reported in the general population. Non-melanoma skin cancer was present in 41% of patients and 17% had squamous cell carcinoma (SCC). The ratio of basal cell carcinoma to SCC in the cohort was 1.7:1. The commonest site of SK was the upper limbs but the greatest density of lesions was on the face, particularly the nose. Squamous cell carcinomas were most commonly found on the upper and lower limbs. Basal cell carcinomas were most common on the head and neck.

The GSTM1 null genotype confers an increased risk for solar keratosis development in an Australian Caucasian population

Solar keratoses affect approximately 50% of Australian Caucasians aged over 40 y. Solar keratoses can undergo malignant transformation into squamous cell carcinoma followed by possible metastasis and are risk factors for basal cell carcinoma, melanoma, and squamous cell carcinoma. The glutathione-S-transferase genes play a part in detoxification of carcinogens and mutagens, including some produced by ultraviolet radiation. This study examined the role of glutathione-S-transferase M1, T1, P1, and Z1 gene polymorphisms in susceptibility to solar keratoses development. Using DNA samples from volunteers involved in the Nambour Skin Cancer Prevention Trial, allele and genotype frequencies were determined using polymerase chain reaction and restriction enzyme digestion. No significant differences were detected in glutathione-S-transferase P1 and glutathione-S-transferase Z1 allele or genotype frequencies; however, a significant association between glutathione-S-transferase M1 genotypes and solar keratoses development was detected (p=0.003) with null individuals having an approximate 2-fold increase in risk for solar keratoses development (odds ratio: 2.1; confidence interval: 1.3-3.5) and a significantly higher increase in risk in conjunction with high outdoor exposure (odds ratio: 3.4; confidence interval: 1.9-6.3). Also, a difference in glutathione-S-transferase T1 genotype frequencies was detected (p=0.039), although considering that multiple testing was undertaken, this was found not to be significant. Fair skin and inability to tan were found to be highly significant risk factors for solar keratoses development with odds ratios of 18.5 (confidence interval: 5.7-59.9) and 7.4 (confidence interval: 2.6-21.0), respectively. Overall, glutathione-S-transferase M1 conferred a significant increase in risk of solar keratoses development, particularly in the presence of high outdoor exposure and synergistically with known phenotypic risk factors of fair skin and inability to tan.

Association between epidermodysplasia verruciformis-associated human papillomavirus DNA in plucked eyebrow hair and solar keratoses

Epidermodysplasia-verruciformis-associated human papillomavirus DNA has been demonstrated in squamous cell carcinomas and plucked hair from immunocompetent patients and renal transplant recipients. This study investigated the association between infection with epidermodysplasia-verruciformis-associated human papillomavirus, identified by the detection of viral DNA in plucked eyebrow hairs, and solar keratoses. These lesions are strongly predictive of squamous cell carcinoma. In a cross-sectional study 518 individuals were enrolled from a randomly selected sample of a subtropical Australian community. Epidermodysplasia-verruciformis-associated human papillomavirus DNA in eyebrow hair was detected using a nested polymerase chain reaction specific for epidermodysplasia-verruciformis-associated human papillomavirus types. Epidermo dysplasia-verruciformis-associated human papillomavirus DNA was present in 121 (49%) of 245 men and 116 (44%) of 262 women. There was a strongly significant increase in epidermodysplasia-verruciformis-associated human papillomavirus infection with age (p < 0.00001), with prevalences of 29% in the 25-39 y age group, 42% at 40-59 y and 65% in the 60-79 y age group. Among men there was a strong association between epidermodysplasia-verruciformis-associated human papillomavirus and solar keratoses with an odds ratio, adjusted for age, skin color, and occupational sun exposure, of 3.40 (95% confidence interval, 1.77-6.53). No such association was found among women [odds ratio 1.03 (95% confidence interval 0.59-1.77, after adjustment for the same factors)]. Differences in occupational sun exposure and smoking histories could not explain these apparently different associations between epidermodysplasia-verruciformis-associated human papillomavirus infection and solar keratoses in men and women. In conclusion, epidermodysplasia-verruciformis-associated human papillomavirus infection is associated with solar keratoses in men suggesting that epidermodysplasia-verruciformis-associated human papillomavirus infection, in conjunction with sex specific factors (like androgens), may be involved in neoplastic changes of keratinocytes.

Melanocortin-1 receptor genotype is a risk factor for basal and squamous cell carcinoma

MC1R gene variants have previously been associated with red hair and fair skin color, moreover skin ultraviolet sensitivity and a strong association with melanoma has been demonstrated for three variant alleles that are active in influencing pigmentation: Arg151Cys, Arg160Trp, and Asp294His. This study has confirmed these pigmentary associations with MC1R genotype in a collection of 220 individuals drawn from the Nambour community in Queensland, Australia, 111 of whom were at high risk and 109 at low risk of basal cell carcinoma and squamous cell carcinoma. Comparative allele frequencies for nine MC1R variants that have been reported in the Caucasian population were determined for these two groups, and an association between prevalence of basal cell carcinoma, squamous cell carcinoma, solar keratosis and the same three active MC1R variant alleles was demonstrated [odds ratio = 3.15 95% CI (1.7, 5.82)]. Three other commonly occurring variant alleles: Val60Leu, Val92Met, and Arg163Gln were identified as having a minimal impact on pigmentation phenotype as well as basal cell carcinoma and squamous cell carcinoma risk. A significant heterozygote effect was demonstrated where individuals carrying a single MC1R variant allele were more likely to have fair and sun sensitive skin as well as carriage of a solar lesion when compared with those individuals with a consensus MC1R genotype. After adjusting for the effects of pigmentation on the association between MC1R variant alleles and basal cell carcinoma and squamous cell carcinoma risk, the association persisted, confirming that presence of at least one variant allele remains informative in terms of predicting risk for developing a solar-induced skin lesion beyond that information wained through observation of pigmentation phenotype.

Risk of nonmelanoma skin cancer in Italian organ transplant recipients. A registry-based study

BACKGROUND

Organ transplant recipients are at an increased risk of nonmelanoma skin cancer. Few data concern heart transplantation and populations from southern Europe.

METHODS

A total of 1,329 patients who received their first kidney (1,062 subjects) or heart allograft (267 subjects) were included in a partly retrospective cohort study to evaluate the risk of skin cancer. The incidence rate per 1,000 person-years and the cumulative incidence were computed. Standardized morbidity ratio was estimated by comparison with Italian cancer registry data. To analyze the role of potential prognostic factors, Cox's regression method was used.

RESULTS

The overall incidence rate of nonmelanoma skin cancer was 10.0 cases per 1,000 posttransplant person-years (95% confidence interval 8.2-11.7). This estimate was far higher than expected in the general population. The overall risk of developing skin cancer increased from a cumulative incidence of 5.8% after 5 posttransplant years to an incidence of 10.8% after 10 years of graft survival. In a Cox proportional hazard risk model, the most important factors that appeared to favor the development of skin cancer were age at transplantation and sex. After adjustment for age at transplantation and sex, no definite increased risk was documented among heart as compared with kindney transplant recipients.

CONCLUSIONS

Our study confirms the increased risk of nonmelanoma skin cancer among organ transplant recipients in a southern European population.

Do forecasts of UV indexes influence people's outdoor behaviour?

OBJECTIVE

To investigate Australian adults' awareness of the ultraviolet (UV) indexes forecast in the media, and whether these UV forecasts influence their behaviour in the sun.

METHODS

A self-administered questionnaire was used on two occasions in 1997 to ask about knowledge of UV indexes shown in the media and about possible influence on outdoor behaviour.

SETTING AND PARTICIPANTS

Participants were 977 residents (423 men; 554 women) of Nambour originally randomly selected in 1986 from the electoral roll, who have been followed up subsequently.

RESULTS

The majority of people--92% of men and 86% of women--reported having seen or heard the UV indexes forecast during summer. Of these, significantly fewer men (107; 28%) than women (209; 46%) reported that their outdoor behaviour was influenced by knowledge of the forecast (p = 0.001). Neither age nor skin type, nor history of sunburns or skin cancer, affected knowledge of UV forecasts or their influence on behaviour.

CONCLUSIONS AND IMPLICATIONS

Although most people are aware of the forecasts of UV indexes in the media, the majority do not take them into account in their outdoor behaviour. Compared with women, men were more aware of, but less influenced by, forecasts of UV indexes. Better communication of the implications of the UV indexes is needed, particularly to men, if they are to adapt their outdoor behaviour to improve their sun protection.