The multicentre south European study 'Helios'. II: Different sun exposure patterns in the aetiology of basal cell and squamous cell carcinomas of the skin

Plasticity of differentiated cells in wound repair and tumorigenesis, part II: skin and intestine

Recent studies have identified and begun to characterize the roles of regenerative cellular plasticity in many organs. In Part I of our two-part Review, we discussed how cells reprogram following injury to the stomach and pancreas. We introduced the concept of a conserved cellular program, much like those governing division and death, which may allow mature cells to become regenerative. This program, paligenosis, is likely necessary to help organs repair the numerous injuries they face over the lifetime of an organism; however, we also postulated that rounds of paligenosis and redifferentiation may allow long-lived cells to accumulate and store oncogenic mutations, and could thereby contribute to tumorigenesis. We have termed the model wherein differentiated cells can store mutations and then unmask them upon cell cycle re-entry the ‘cyclical hit’ model of tumorigenesis. In the present Review (Part II), we discuss these concepts, and cell plasticity as a whole, in the skin and intestine. Although differentiation and repair are arguably more thoroughly studied in skin and intestine than in stomach and pancreas, it is less clear how mature skin and intestinal cells contribute to tumorigenesis. Moreover, we conclude our Review by discussing plasticity in all four organs, and look for conserved mechanisms and concepts that might help advance our knowledge of tumor formation and advance the development of therapies for treating or preventing cancers that might be shared across multiple organs.

Summary: This final installment of a two-part Review discusses how cycles of dedifferentiation and redifferentiation can promote tumorigenesis in the skin and intestine, showing how plasticity in these continuously renewing tissues might contribute to tumorigenesis.

Risk of Basal and Squamous Cell Carcinomas of the Skin in Sion, Switzerland: A Case-control Study

Aims and Background

Non-melanocytic skin cancers are the most common cancers in white populations. Studies on populations of Anglo-Saxon and Mediterranean origins highlighted different patterns of risk of basal-cell carcinoma and squamous-cell carcinoma in relation to sunlight exposure, skin characteristics and phenotype susceptibility. In Sion, and in Switzerland as a whole, the high incidence suggests the possible presence of additional risk factors or of a different pattern of exposure to solar radiation as well as different composition of pigmentary traits and skin sensitivity to sun.

Methods and Study Design

We conducted a case-control study of 146 cases (73% of eligible cases) and 144 controls (81% of eligible subjects) to further evaluate the relationship between nonmelanocytic skin cancer and risk factors in the Sion population. Interviews were conducted by trained interviewers with a standardized questionnaire.

Results

Pigmentary characteristics such as blonde and red hair as well as tendency to sunburn without tanning and number of sunburns showed a statistically significant and independent risk increase in basal-cell carcinoma. Sun exposure during recreational activities (outdoor sports) showed a risk increase in basal-cell carcinoma with borderline statistical significance. Analysis of squamous-cell carcinoma risk was limited by the small number of cases, but it was positively associated with lifetime exposure to sun during outdoor work and with skin characteristics.

Conclusions

Results confirmed previous suggestions of a different mechanism leading to malignant transformation of target cells from the basal and squamous epidermal layers, mediated by different phenotypes, and conditioning the ability to develop an effectively protective tan.

Reproducibility of Histopathologic Diagnosis and Classification of Non-Melanocytic Skin Cancer: A Panel Exercise in the Framework of the Multicenter Southern European Study Helios

Aims and background

The reproducibility of histologic diagnoses, and in particular of the distinction between basal and squamous cell forms, has been evaluated in the framework of a multicenter case-control study (in Italy, France, Spain and Switzerland) aimed to assess the causes of non-melanocytic skin cancers.

Methods

A panel composed of 10 pathologists from the collaborating centers was appointed. A total of 1774 slides of routine diagnoses were blindly reviewed by a second panelist; discordant diagnoses underwent a third examination. Controversial and interesting cases were discussed during general sessions.

Results

The results showed a high degree of concordance (99.5%), with a Cohen's kappa of 0.85 (95% CI, 0.77–0.94) in the assessment of malignancy of lesions. The concordance in the distinction between large morphologic groups, basal cell carcinoma and squamous cell carcinoma was also high (Cohen's kappa = 0.85; 95% CI, 0.82–0.89). The assessment of histologic subtypes, degree of invasion and differentiation showed a lower degree of concordance, presumably as a consequence of a weaker consistency in the relevant classifications.

Conclusions

The reproducibility study has therefore validated the epidemiologic study and in particular allowed to correct some misclassifications that could have lessened the analysis of the case-control study. In general, because of its characteristics (number of pathologists and variety of their origins, the large number of cases examined, blind examination of histologic slides), the conclusions of the study may show a certain degree of generalization, at least with regard to the countries represented. Routine histologic diagnoses of cutaneous carcinoma showed a high degree of reliability with reference to the assessment of malignancy and the distinction between basal and squamous cell carcinoma morphotypes.

Retrospective evaluation of exposure to natural UV radiation: experiences with the online UV history tool in a field study

BACKGROUND

Cutaneous squamous cell carcinoma and multiple actinic keratoses can be recognized as occupational diseases if the site affected has been subjected to additional occupational UV exposure of at least 40 %. An online UV history tool that allows for the quantification of occupational and recreational UV doses was now tested in a field study.

PATIENTS AND METHODS

Ninety-nine patients with nonmelanoma skin cancer were examined. Patient history with respect to UV exposure was obtained using the online UV history tool. Initial validation was carried out with data from ten additional patients. In the context of a pilot study, the applicability of the tool was assessed using a questionnaire.

RESULTS

Overall, patient history revealed a UV exposure between 3,792 and 53,163 SEDs. Patients with squamous cell carcinoma, actinic keratoses, or Bowen's disease (n  =  22) had significantly higher SED values and were significantly older (73 vs. 66 years) than patients with basal cell carcinoma (n  =  77). Occupational UV exposure was reported by 19 patients, two of whom showed an additional occupational UV exposure of more than 40 %, which prompted the filing of a (suspected) occupational disease report. With respect to validation, there was evidence of good inter-investigator reliability. The applicability of the tool was rated as good.

CONCLUSIONS

The online UV history tool enables quick retrospective quantification of occupational and recreational UV exposure in case of suspicion of the occupational disease "cutaneous squamous cell carcinoma or multiple actinic keratoses caused by natural UV radiation".

Emerging concepts and recent advances in basal cell carcinoma

Basal cell carcinoma (BCC) is the most common malignancy worldwide, arising from non-keratinizing cells within the basal layer of the epidermis. The incidence of BCC continues to rise annually, increasing the burden of management of these carcinomas and the morbidity associated with their treatment. While surgical interventions such as Mohs micrographic surgery and surgical excision are the standard of care and yield the highest cure rates, the number of non-surgical interventions approved for the treatment of BCC continues to expand. We review various surgical and non-surgical approaches to the treatment of BCC, focusing on targeted molecular therapies that are approved for locally advanced or recurrent disease.

Metal arc welding and the risk of skin cancer

OBJECTIVES

Arc welding produces the full spectrum of ultraviolet radiation and may be a contributory cause of skin cancer; however, there has been little research into this occupational hazard. The aim of this study is to explore if metal arc welding increases the risk of malignant melanoma and/or basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) on skin areas which may possibly be exposed (neck, head, and upper extremities).

METHOD

A Danish national company-based historic cohort of 4333 male metal arc welders was followed from 1987 through 2012 to identify the risk of skin cancer. An external reference group was established including all Danish skilled and unskilled male workers with similar age distribution. Occupational histories were gathered by questionnaires in 1986 and information about skin cancer diagnoses [BCC, SCC, cutaneous malignant melanoma (CMM), and precancerous conditions, actinic keratosis (AK)] were gathered from the Danish Cancer Registry supplemented by the data from the Danish Pathology Register. Hazard ratios (HRs) were calculated in the follow-up period from 1987 until 2012 using Cox regression analysis and adjusted for baseline data regarding age and social group.

RESULTS

The adjusted HR and 95% confidence interval (CI) for skin cancer (all types) were 0.99 (CI 0.94-1.04) for welders. The adjusted HR for AK and BCC located only at neck was 2.49 (CI 1.03-5.99) for welders exposed >20 years (n = 5) and 2.46 (CI 1.02-5.94), respectively, for welders exposed >30 years (n = 5). No statistically significant difference was observed for SCC. The risk of CMM at the neck was also significantly elevated after 30 years of welding, but this is based upon only one exposed case.

CONCLUSION

This study indicates that long-term exposure to metal arc welding may be related to increased risk of BCC and AK located exclusively at the neck. The study provides no support for the hypothesis that welding exposure increases the risk for skin cancer at other locations.

Macrophage subtypes in recurrent nodular basal cell carcinoma after Mohs micrographic surgery

BACKGROUND

The macrophages associated with solid tumors are related to the progression or regression of tumors, depending on the differentiation in M1 or M2. M2 subtype promotes angiogenesis, remodeling, and tissue repair (tumor proliferation). In contrast, M1 produces toxic mediators and presents antigens, destroying microorganisms and tumor cells. The microenvironment of most aggressive forms of basal cell carcinoma (BCC) shows an increase in macrophages due to M2 phenotype compared to noninvasive forms. The treatment of nodular BCC by Mohs micrographic surgery (MMS) provides high cure rates, but relapses can occur.

AIMS

To compare the total population of macrophages and their subpopulations M1 and M2 in cases of recurrent and nonrecurrent nodular BCC after excision by MMS.

MATERIALS & METHODS

Histological sections obtained from paraffin blocks of nine cases of recurrent nodular BCC after MMS and 18 cases of nonrecurrent nodular BCC operated by MMS were immunostained for iNOS, CD204, CD163, and CD68. The expression of these markers was analyzed by image analysis.

RESULTS

No significant differences were found between the groups in relation to the average percentage of M1 cells, M2 cells, and total cells.

DISCUSSION AND CONCLUSION

A relationship was not seen between tumor-associated macrophages (TAM) and tumor recurrence.

Early Life UV and Risk of Basal and Squamous Cell Carcinoma in New South Wales, Australia

Sun exposure is the main cause of squamous (SCC) and basal cell carcinoma (BCC) although pattern and amount differ by cancer type, and sun sensitivity is the major host risk factor. Our study investigated risk factors and residential ambient UV in a population-based sample of Australian 45 and Up Study participants: 916 BCC cases, 433 SCC cases, 1224 controls. Unconditional logistic regression models adjusting for key covariates demonstrated 60% increased BCC risk and two-fold increased SCC risk with sun sensitivity, and three- and four-fold increased risk, respectively, with solar keratoses. BCC but not SCC risk increased with higher early-life residential UV in all participants (odds ratio (OR) = 1.54; 95% CI 1.22-1.96 for intermediate; OR = 1.31; 95% CI 1.03-1.68 for high UV at birthplace) and similarly in Australian-born participants (P-values < 0.05). Risk of SCC but not BCC increased with long-term cumulative sun exposure assessed by self-reported outdoor work (OR 1.74, 95% CI 1.21-2.49). In conclusion, sun sensitivity is important for both cancers, early-life UV but not cumulative UV appears to increase BCC risk, the former an apparently novel finding, and SCC risk appears only to be related to long-term cumulative sun exposure.

Vitamin D3 Produced by Skin Exposure to UVR Inhibits Murine Basal Cell Carcinoma Carcinogenesis

The effect of UVR on human basal cell carcinoma (BCC) epidemiology is complex-the incidence rises until approximately 30,000 hours of lifetime sunlight exposure and then plateaus. We hypothesize that UVR has opposing effects on BCC carcinogenesis-stimulatory via mutagenesis and inhibitory via production of hedgehog-inhibiting vitamin D₃ (D₃). We find that UVR exposure of ionizing radiation-treated Ptch1^+/- mice accelerates BCC carcinogenesis in male mice, in which UVR does not produce D₃. By contrast, in female mice, in which UVR does produce D₃, UVR fails to accelerate BCC carcinogenesis, thus mirroring the plateauing in humans. However, if D₃ production is attenuated in female mice by deletion of keratinocyte lathosterol 5-desaturase, then UVR accelerates ionizing radiation-induced BCC carcinogenesis. Congruently, chronic topical application of D₃ inhibits ionizing radiation-induced BCC tumorigenesis. These findings confirm that UVR-induced production of D₃ in keratinocytes significantly restrains murine BCC tumorigenesis and demonstrate the counterintuitive conclusion that UVR has anti-BCC carcinogenic effects that can explain, at least in part, the complex relationship between exposure to UVR and BCC incidence.

Clinical and prognostic factors in the development of basal cell carcinoma

We investigated the environmental and personal risk factors associated with the development of basal cell carcinoma (BCC). This retrospective cohort study included a total of 997 patients whose diagnosis was confirmed by histopathologic examination between 2007 and 2014. A control examination was performed in 363 of these patients, who were accessed via telephone. A total of 1151 tumors were detected in 997 patients. During their follow-up, 13% of them developed subsequent tumors. The risk of developing subsequent tumor was 2.7-fold higher in patients with multiple BCCs at the time of diagnosis than those with single BCC. Multiple BCCs tended to develop in older patients and men. The risk of developing multiple BCCs was increased in patients with a history of BCC, skin type 1 or 2, and chronic sun exposure (sun exposure of >500 weeks, a high photoaging score [≥30], and the presence of actinic keratosis). We concluded that chronic sun exposure may increase the risk of developing multiple BCCs. These data also indicate that cumulative sun exposure is as important for developing BCC as for squamous cell carcinoma.

BlueHealth: a study programme protocol for mapping and quantifying the potential benefits to public health and well-being from Europe's blue spaces

INTRODUCTION

Proximity and access to water have long been central to human culture and accordingly deliver countless societal benefits. Over 200 million people live on Europe's coastline, and aquatic environments are the top recreational destination in the region. In terms of public health, interactions with 'blue space' (eg, coasts, rivers, lakes) are often considered solely in terms of risk (eg, drowning, microbial pollution). Exposure to blue space can, however, promote health and well-being and prevent disease, although underlying mechanisms are poorly understood.

AIMS AND METHODS

The BlueHealth project aims to understand the relationships between exposure to blue space and health and well-being, to map and quantify the public health impacts of changes to both natural blue spaces and associated urban infrastructure in Europe, and to provide evidence-based information to policymakers on how to maximise health benefits associated with interventions in and around aquatic environments. To achieve these aims, an evidence base will be created through systematic reviews, analyses of secondary data sets and analyses of new data collected through a bespoke international survey and a wide range of community-level interventions. We will also explore how to deliver the benefits associated with blue spaces to those without direct access through the use of virtual reality. Scenarios will be developed that allow the evaluation of health impacts in plausible future societal contexts and changing environments. BlueHealth will develop key inputs into policymaking and land/water-use planning towards more salutogenic and sustainable uses of blue space, particularly in urban areas.

ETHICS AND DISSEMINATION

Throughout the BlueHealth project, ethics review and approval are obtained for all relevant aspects of the study by the local ethics committees prior to any work being initiated and an ethics expert has been appointed to the project advisory board. So far, ethical approval has been obtained for the BlueHealth International Survey and for community-level interventions taking place in Spain, Italy and the UK. Engagement of stakeholders, including the public, involves citizens in many aspects of the project. Results of all individual studies within the BlueHealth project will be published with open access. After full anonymisation and application of any measures necessary to prevent disclosure, data generated in the project will be deposited into open data repositories of the partner institutions, in line with a formal data management plan. Other knowledge and tools developed in the project will be made available via the project website (www.bluehealth2020.eu). Project results will ultimately provide key inputs to planning and policy relating to blue space, further stimulating the integration of environmental and health considerations into decision-making, such that blue infrastructure is developed across Europe with both public health and the environment in mind.

Effect of an intervention on observed sun protection by vacationers in a randomized controlled trial at North American resorts

During vacations, many individuals receive high-risk sun exposure that is associated with skin cancer. Vacationers in outdoor recreation venues (pretest n=4347; posttest n=3986) at warm-weather destination resorts in North America (n=41) were enrolled in a pair-matched, group-randomized pretest-posttest controlled quasi-experimental design in 2012-14. Print, audiovisual, and online messages based on Transportation Theory and Diffusion of Innovation Theory and promoting advanced sun protection (e.g., use of clothing, hats, shade and pre-application/reapplication of sunscreen and reliable cues to high UV) were delivered through resort channels. Vacationers' sun protection practices observed by trained research staff (i.e., body coverage and shade use analyzed individually and in combined scores) did not differ by experimental condition (p>0.05) or intervention implementation (p>0.05). However, recreation venue moderated intervention impact. The intervention improved sun protection at waterside recreation venues (z-score composite: intervention pre=-22.74, post=-15.77; control pre=-27.24, post=-23.24) but not non-waterside venues (z-score composite: intervention pre=20.43, post=20.53; control pre=22.94, post=18.03, p<0.01). An additional analysis showed that resorts with greater program implementation showed more improvements in sun protection by vacationers at waterside (z=score composite: high implementation pre=-25.45, post=-14.05; low implementation pre=-24.70, post=-21.40) compared to non-waterside (z-score composite: high implementation pre=14.51, post=19.98; low implementation pre=24.03, post=18.98, p<0.01) recreation venues. The intervention appeared effective with the vacationers in recreation venues with the highest-risk for sun exposure, waterside venues. However, it was not effective throughout all the resort venues, possibly because of the sun-seeking desires of vacationers, information overload at the resorts, and constraints on clothing styles and sun protection by recreation activity.

Management of a cutaneous squamous cell carcinoma overlying an AV fistula

Cutaneous squamous cell carcinoma (cSCC) currently affects over 700 000 patients per year in the USA alone, and its incidence continues to rise in recent years. A known risk factor for cSCC is chronic inflammation; a cSCC that develops at a site of chronic inflammation is known as Marjolin's ulcer. We present the case of a 76-year-old man with end-stage renal disease requiring chronic haemodialysis who developed an invasive cSCC at the cannulation site of an underlying arteriovenous (AV) fistula. In this instance, treatment with standard surgical excision or Mohs surgery would pose unique risks associated with injury to an otherwise functional AV fistula. Thus, the lesion was treated with electron beam radiation therapy, which offers a similar efficacy to surgery while minimising risk to the fistula. This resulted in a successful oncological outcome with no complications.

Cutaneous squamous cell carcinoma: an epidemiological review

Cutaneous squamous cell carcinoma (SCC) is a common cancer in white populations and its disease burden is often substantially underestimated. SCC occurs more often in men than women and increases dramatically with age; those affected often develop multiple primaries over time, which increases the burden. The main external cause is solar ultraviolet radiation (UVR), with immunosuppression being the other established risk factor, shown by the high SCC rates in organ transplant recipients. Sunbed use and certain genetic disorders and medical conditions are also associated with SCC, while associations with human papillomavirus infection and high bodyweight are not established. The presence of actinic keratoses (AKs) on sun-damaged skin is one of the strongest predictors of SCC in unaffected people and a very small proportion of AKs are SCC precursors, although the true rate of malignant transformation of AKs is unknown. The mainstay of SCC prevention is protection of the skin from undue sun exposure by use of clothing cover and sunscreen during summer or in sunny places. Educational, behavioural and multicomponent interventions directed at individuals ranging from parents of newborns, to school children and adolescents, to outdoor workers, have repeatedly been shown to be effective in improving sun-protective behaviours. Health policies can facilitate SCC prevention by setting standards for relevant behaviours to reduce UVR exposure, for example, by legislated restriction of the tanning industry. Skin cancer prevention initiatives are generally highly cost-effective and public investment should be encouraged to control the growing public health problems caused by SCC.

Rationale, design, and baseline data of a cross-national randomized trial on the effect of built shade in public parks for sun protection

Environments can be structured to reduce solar ultraviolet radiation (UV) exposure to prevent skin cancer. A prospective randomized trial is being conducted to test whether introducing shade sails in passive recreation areas (PRAs) in public parks will increase use and decrease UV exposure in the shaded compared to unshaded PRAs. Shade effects will be compared between Melbourne, Australia and Denver, USA. The trial enrolled 145 public parks with PRAs suitable for shade construction and randomized parks to intervention or control in a 1:3 ratio. Use of PRAs and UV levels were recorded at each park by trained observers during 30-minute periods on four weekend days in each of two summers (pretest and posttest). Shade sails were constructed between the summers. Given low numbers of users at pretest, the outcome measure was modified to use of the PRA (use vs. no use) and unit of analysis to the individual observation. Observations (n=580) occurred on average 29days from the summer solstice and 55min from solar noon in warm weather (mean=26.2°C) with some cloud cover but only slight or no wind. Typically, PRAs had benches and picnic tables and were located near playgrounds. PRAs were in use during 13.3% of observations (mean=0.41 users). UV over 30-minutes at the PRA boundary (mean=3.2 standard erythemal dose [SED]) and center (mean=3.3 SED) was high. Shade for skin cancer prevention has been understudied. This study will address this gap by determining whether purpose-built shade structures promote greater use of shaded areas within public parks.

Herbal Extracts That Reduce Ocular Oxidative Stress May Enhance Attentive Performance in Humans

We used herbal extracts in this study to investigate the effects of blue-light-induced oxidative stress on subjects' attentive performance, which is also associated with work performance. We employed an attention network test (ANT) to measure the subjects' work performance indirectly and used herbal extracts to reduce ocular oxidative stress. Thirty-two subjects participated in either an experimental group (wearing glasses containing herbal extracts) or a control group (wearing glasses without herbal extracts). During the ANT experiment, we collected electroencephalography (EEG) and electrooculography (EOG) data and measured button responses. In addition, electrocardiogram (ECG) data were collected before and after the experiments. The EOG results showed that the experimental group exhibited a reduced number of eye blinks per second during the experiment and faster button responses with a smaller variation than did the control group; this group also showed relatively more sustained tension in their ECG results. In the EEG analysis, the experimental group had significantly greater cognitive processing, with larger P300 and parietal 2–6 Hz activity, an orienting effect with neural processing of frontal area, high beta activity in the occipital area, and an alpha and beta recovery process after the button response. We concluded that reducing blue-light-induced oxidative stress with herbal extracts may be associated with reducing the number of eye blinks and enhancing attentive performance.

A programme of research to set priorities and reduce uncertainties for the prevention and treatment of skin disease

Background

Skin diseases are very common and can have a large impact on the quality of life of patients and caregivers. This programme addressed four diseases: (1) eczema, (2) vitiligo, (3) squamous cell skin cancer (SCC) and (4) pyoderma gangrenosum (PG).

Objective

To set priorities and reduce uncertainties for the treatment and prevention of skin disease in our four chosen diseases.

Design

Mixed methods including eight systematic reviews, three prioritisation exercises, two pilot randomised controlled trials (RCTs), three feasibility studies, two core outcome initiatives, four funding proposals for national RCTs and one completed national RCT.

Setting

Secondary care, primary care and the general population.

Participants

Patients (and their caregivers) with eczema, vitiligo, SCC and PG, plus health-care professionals with an interest in skin disease.

Interventions

Our three intervention studies included (1) barrier enhancement using emollients from birth to prevent eczema (pilot RCT); (2) handheld narrowband ultraviolet light B therapy for treating vitiligo (pilot RCT); and (3) oral ciclosporin (Neoral®, Novartis Pharmaceuticals) compared with oral prednisolone for managing PG (pragmatic national RCT).

Results

Systematic reviews included two overarching systematic reviews of RCTs of treatments for eczema and vitiligo, an umbrella review of systematic reviews of interventions for the prevention of eczema, two reviews of treatments for SCC (one included RCTs and the second included observational studies), and three reviews of outcome measures and outcome reporting. Three prioritisation partnership exercises identified 26 priority areas for future research in eczema, vitiligo and SCC. Two international consensus initiatives identified four core domains for future eczema trials and seven core domains for vitiligo trials. Two pilot RCTs and three feasibility studies critically informed development of four trial proposals for external funding, three of which are now funded and one is pending consideration by funders. Our pragmatic RCT tested the two commonly used systemic treatments for PG (prednisolone vs. ciclosporin) and found no difference in their clinical effectiveness or cost-effectiveness. Both drugs showed limited benefit. Only half of the participants’ ulcers had healed by 6 months. For those with healed ulcers, recurrence was common (30%). Different side effect profiles were noted for each drug, which can inform clinical decisions on an individual patient basis. Three researchers were trained to PhD level and a dermatology patient panel was established to ensure patient involvement in all aspects of the programme.

Conclusions

Findings from this programme of work have already informed clinical guidelines and patient information resources. Feasibility studies have ensured that large national pragmatic trials will now be conducted on important areas of treatment uncertainty that address the needs of patients and the NHS. There is scope for considerable improvement in terms of trial design, conduct and reporting for RCTs of skin disease, which can be improved through wider collaboration, registration of trial protocols and complete reporting and international consensus over core outcome sets. Three national trials have now been funded as a result of this work. Two international initiatives to establish how best to measure the core outcome domains for eczema and vitiligo are ongoing.

Trial registration

Current Controlled Trials Barrier Enhancement for Eczema Prevention (BEEP) (ISRCTN84854178 and NCT01142999), Study of Treatments fOr Pyoderma GAngrenosum Patients (STOP GAP) (ISRCTN35898459) and Hand Held NB-UVB for Early or Focal Vitiligo at Home (HI-Light Pilot Trial) (NCT01478945).

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full inProgramme Grants for Applied Research; Vol. 4, No. 18. See the NIHR Journals Library website for further project information.

Repeated Treatments with Ingenol Mebutate Prevents Progression of UV-Induced Photodamage in Hairless Mice

Background and Aim

Ingenol mebutate (IngMeb) is an effective treatment for actinic keratosis. In this study, we hypothesized that repeated treatments with IngMeb may prevent progression of UV-induced photodamage, and that concurrent application of a corticosteroid may reduce IngMeb-induced local skin responses (LSR).

Methods

Hairless mice (n = 60; 3 groups of 20 mice) were irradiated with solar simulated ultraviolet radiation (UVR) throughout the study. Five single treatments with IngMeb were given at 4-week intervals (Days 21, 49, 77, 105, and 133). Clobetasol propionate (CP) was applied once daily for 5 days prior to each IngMeb application, as well as 6 h and 1 day post treatment. One week after IngMeb treatment No. 1, 3, and 5 (Days 28, 84, and 140), biopsies from four mice in each group were collected for histological evaluation of UV-damage on a standardized UV-damage scale (0–12). LSR (0–24) were assessed once daily (Days 1–7) after each IngMeb treatment.

Results

IngMeb prevented progression of photodamage in terms of keratosis grade, epidermal hypertrophy, dysplasia, and dermal actinic damage with a lower composite UV-damage score on day 140 (UVR 10.25 vs. UVR+IngMeb 6.00, p = 0.002) compared to UVR alone. IngMeb induced LSR, including erythema, flaking, crusting, bleeding, vesiculation, and ulceration. Concurrent CP increased LSR (max LSR Tx 1–5: UVR+IngMeb+CP 3.6–5.5 vs. UVR+IngMeb 2.6–4.3) and provided better prevention of photodamage compared to IngMeb alone (Day 140: UVR+IngMeb 6.00 vs. UVR+IngMeb+CP 3.00 p < 0.001).

Conclusion

Repeated field-directed treatments with IngMeb prevent progression of cutaneous photodamage in hairless mice, while CP cannot be used to alleviate IngMeb-induced LSR. The findings suggest that IngMeb may potentially serve as a prophylactic treatment for UV-induced tumors.

Shave to Save Face

BACKGROUND

Basal cell carcinoma (BCC) is the most common cutaneous malignancy. Terminal hair is not routinely removed for assessment of BCCs on the scalp and yet may obscure the true size of scalp BCCs. This can compromise effective management.

OBJECTIVE

To underscore the importance of removing terminal hair on the scalp for an accurate assessment of clinical margins of BCC on the scalp.

METHODS

We report 2 cases of cutaneous BCC arising on the scalp. The size of the malignancies was underestimated because they were masked by hair growth.

RESULTS

Removing terminal hair allowed for a full assessment of the extent of the tumours on hair-bearing scalp, which had been underestimated by 73% to 80% prior to shaving.

CONCLUSION

Our cases highlight the importance of hair removal for complete assessment of cutaneous malignancy occurring on hair-bearing skin.

Disruption of Vitamin D and Calcium Signaling in Keratinocytes Predisposes to Skin Cancer

1,25 dihydroxyvitamin D (1,25(OH)₂D), the active metabolite of vitamin D, and calcium regulate epidermal differentiation. 1,25(OH)₂D exerts its effects through the vitamin D receptor (VDR), a transcription factor in the nuclear hormone receptor family, whereas calcium acts through the calcium sensing receptor (Casr), a membrane bound member of the G protein coupled receptor family. We have developed mouse models in which the Vdr and Casr have been deleted in the epidermis (^epidVdr^−∕− and ^epidCasr^−∕−). Both genotypes show abnormalities in calcium induced epidermal differentiation in vivo and in vitro, associated with altered hedgehog (HH) and β–catenin signaling that when abnormally expressed lead to basal cell carcinomas (BCC) and trichofolliculomas, respectively. The Vdr^−∕− mice are susceptible to tumor formation following UVB or chemical carcinogen exposure. More recently we found that the keratinocytes from these mice over express long non-coding RNA (lncRNA) oncogenes such as H19 and under express lncRNA tumor suppressors such as lincRNA-21. Spontaneous tumors have not been observed in either the ^epidVdr^−∕− or ^epidCasr^−∕−. But in mice with epidermal specific deletion of both Vdr and Casr (^epidVdr^−∕−/^epidCasr^−∕− [DKO]) tumor formation occurs spontaneously when the DKO mice are placed on a low calcium diet. These results demonstrate important interactions between vitamin D and calcium signaling through their respective receptors that lead to cancer when these signals are disrupted. The roles of the β–catenin, hedgehog, and lncRNA pathways in predisposing the epidermis to tumor formation when vitamin D and calcium signaling are disrupted will be discussed.

Non-melanoma Skin Cancer in Canada Chapter 5: Management of Squamous Cell Carcinoma

Background

Squamous cell carcinoma (SCC) is the second-most common form of non-melanoma skin cancer (NMSC).

Objective

To provide guidance to Canadian health care practitioners regarding management of SCCs.

Methods

Literature searches and development of graded recommendations were carried out as discussed in the accompanying introduction (chapter 1 of the NMSC guidelines).

Results

SCCs are sometimes confined to the epidermis, but they can also invade nearby tissues and, in some cases, metastasize to neighbouring lymph nodes or other organs. This chapter discusses the natural history, staging, prognosis, and management of SCC—a tumour type that is less common but typically more aggressive than BCC. For this reason, margin control is strongly preferred in treating SCCs.

Conclusions

Although approaches such as cryosurgery and radiation therapy may be considered for some patients, surgical excision—sometimes coupled with radiation—remains the cornerstone of SCC management. Patients with high-risk SCC may also be considered for referral to an appropriate multidisciplinary clinic.

Randomized Trial Testing a Worksite Sun Protection Program in an Outdoor Recreation Industry

Health communication campaigns intended to reduce chronic and severe exposure to ultraviolet radiation in sunlight and prevent skin cancer are a national priority. Outdoor workers represent an unaddressed, high-risk population. Go Sun Smart (GSS), a worksite sun safety program largely based on the diffusion-of-innovations theory, was evaluated in a pair-matched, group-randomized, pretest-posttest controlled design enrolling employees at 26 ski areas in Western North America. Employees at the intervention ski areas were more aware of GSS (odds ratio [OR] = 8.27, p < .05) and reported less sunburning (adjusted OR = 1.63, p < .05) at posttest than employees at the control areas. A dose response was evident (OR = 1.46, p < .05) with greater observed program implementation associated with fewer sunburns among employees. Program awareness per se was not predictive ( p > .05) of reduced sunburning in a mediational analysis. Analyses of nonrespondents, including intent-to-treat analyses, further supported the success of GSS.

Is early detection of basal cell carcinoma worthwhile? Systematic review based on the WHO criteria for screening

The incidence of basal cell carcinoma (BCC) has risen three- to fourfold over the last 30 years and is expected to continue to increase with ageing of the population. Although BCC has a good prognosis, it causes significant morbidity and has an important impact on the public health budget due to direct treatment costs. Based on the existing evidence, a systematic evaluation of the World Health Organization criteria was performed to determine whether earlier detection of BCC could reduce morbidity and cost. BCC slowly increases in size, with a median increase in diameter of 0·5 mm over 10 weeks. There is an important delay in diagnosis ranging from 19 to 25 months. In several studies BCC size was the main determinant of treatment cost, surgical complexity, reconstruction technique and the specific surgical procedure performed, such as Mohs micrographic surgery or surgical excision. One study showed that size also seems to affect the cost per treatment for other nonsurgical options. The use of vismodegib, an inhibitor of the hedgehog pathway, is confined to locally advanced or metastatic BCC. Delays in diagnosis and appropriate treatment are the most important underlying causes in the occurrence of giant BCC and/or BCC with metastasis. Although the latter represent only a very small fraction of all BCCs, the majority of them are located in the facial region. The available data point to a slow increase in the size of BCCs over time. Size is one of the major determinants in choice of treatment and the associated cost, especially for facial BCC. Therefore we conclude that current data support early detection and adequate management of BCCs on the face.

Sunburn and sun-protective behaviors among adults with and without previous nonmelanoma skin cancer (NMSC): A population-based study

BACKGROUND

Individuals with previous nonmelanoma skin cancer (NMSC) are at increased risk for subsequent skin cancer, and should therefore limit ultraviolet exposure.

OBJECTIVE

We sought to determine whether individuals with previous NMSC engage in better sun protection than those with no skin cancer history.

METHODS

We pooled self-reported data (2005 and 2010 National Health Interview Surveys) from US non-Hispanic white adults (758 with and 34,161 without previous NMSC). We calculated adjusted prevalence odds ratios (aPOR) and 95% confidence intervals (CI), taking into account the complex survey design.

RESULTS

Individuals with previous NMSC versus no history of NMSC had higher rates of frequent use of shade (44.3% vs 27.0%; aPOR 1.41; 95% CI 1.16-1.71), long sleeves (20.5% vs 7.7%; aPOR 1.55; 95% CI 1.21-1.98), a wide-brimmed hat (26.1% vs 10.5%; aPOR 1.52; 95% CI 1.24-1.87), and sunscreen (53.7% vs 33.1%; aPOR 2.11; 95% CI 1.73-2.59), but did not have significantly lower odds of recent sunburn (29.7% vs 40.7%; aPOR 0.95; 95% CI 0.77-1.17). Among those with previous NMSC, recent sunburn was inversely associated with age, sun avoidance, and shade but not sunscreen.

LIMITATIONS

Self-reported cross-sectional data and unavailable information quantifying regular sun exposure are limitations.

CONCLUSION

Physicians should emphasize sunburn prevention when counseling patients with previous NMSC, especially younger adults, focusing on shade and sun avoidance over sunscreen.

Basal cell skin cancer and the risk of second primary cancers: a cancer registry-based study in Lithuania

PURPOSE

The aim of this population-based cohort study was to determine the risk of second primary cancer in basal cell carcinoma (BCC) patients in Lithuania.

METHODS

This analysis was based on patients diagnosed with BCC in Lithuania between 1998 and 2007 and followed until 2011. Standardized incidence ratios for subsequent cancers as a ratio of observed number of cancer cases in people with previous BCC diagnosis to the expected number of cancer cases in the underlying general population were calculated.

RESULTS

After diagnosis of BCC, 1442 new cases of selected cancers were diagnosed. Compared with the general population, the incidence of all new primaries combined after BCC was very close to expected. Statistically meaningful increase in developing subsequent cancer was obtained for Hodgkin's lymphoma, prostate cancer, and leukemia in men, and for cancers of the lip, lung, and breast in women. Risk of melanoma and thyroid cancer was significantly elevated in both sexes. Relative risk of cancer of the eye was increased although not significant.

CONCLUSIONS

In our study, we found increased cancer risk for cancers related to sun exposure. In addition, increased risks were identified for Hodgkin's lymphoma, thyroid cancer, leukemia, prostate, and breast cancer in BCC patients.

An Italian population-based case-control study on the association between farming and cancer: Are pesticides a plausible risk factor?

This population-based case-control study investigated the association between farming (a proxy for pesticide exposure) and cancer in the Vercelli suburban area (northwest Italy). The residents, aged 25 to 79 years, in the above-mentioned area during the period 2002-2009 were considered. Cases were all the first hospital admissions for cancer. Controls were all the subjects not included in the cases and not excluded from the study. Cases and controls were classified according to whether they occupationally resulted farmers or nonfarmers during the period 1965-2009. Cancer odds ratios (ORs) between farmers and nonfarmers were calculated with generalized linear mixed models adjusted by gender and age. Farmers showed higher odds for all cancers (OR=1.459; p < .001), nonmelanoma skin cancer, colorectal cancer, and breast cancer. The results suggest a plausible association between pesticide exposure and cancer occurrence.

[Management of eyelid carcinomas: Retrospective bicentric study of 64 cases and review of the literature]

PURPOSE

To study the epidemiologic, clinical and histological aspects of eyelid carcinomas in our context, and to evaluate our surgical management on an oncological, functional and aesthetic level.

PATIENTS AND METHODS

This work is a retrospective bicentric study extended over a 5-year period between January 2009 and December 2013, including 64 patients with eyelid carcinoma undergoing surgery in the Plastic and Reconstructive Surgery Department at the Avicenne University Hospital of Rabat and in the ENT/Head and Neck Surgery Department at the Hassan II University Hospital of Fez.

RESULTS

The study included 25 men and 39 women with a mean age of 60.6 ± 15.33 years. Advanced age and chronic sun exposure were the most important risk factors. The most commonly involved site was the lower eyelid (53%). Histological examination emphasized the very high prevalence of basal cell carcinoma (90.62%). Surgical treatment was performed in all our patients followed by an extemporaneous and/or standard histological examination of the surgical specimen. Exenteration was performed in one patient with adjuvant radiation therapy. Reconstruction incorporated a variety of techniques, of which total skin graft and Mustardé flap were the most common in our series. Aside from a few complications, the postoperative results were satisfactory for the majority of our patients.

CONCLUSION

Malignant tumors of the eyelids, of which basal cell carcinoma is the most common, pose a therapeutic problem where surgery remains the most utilized treatment option. The best treatment is prevention and diagnosis of early lesions to improve prognosis and to avoid worse outcomes.

Estimation of individual cumulative ultraviolet exposure using a geographically-adjusted, openly-accessible tool

Background

Estimates of an individual’s cumulative ultraviolet (UV) radiation exposure can be useful since ultraviolet radiation exposure increases skin cancer risk, but a comprehensive tool that is practical for use in the clinic does not currently exist.

The objective of this study is to develop a geographically-adjusted tool to systematically estimate an individual’s self-reported cumulative UV radiation exposure, investigate the association of these estimates with skin cancer diagnosis, and assess test reliability.

Methods

A 12-item online questionnaire from validated survey items for UV exposure and skin cancer was administered to online volunteers across the United States and results cross-referenced with UV radiation indices. Cumulative UV exposure scores (CUES) were calculated and correlated with personal history of skin cancer in a case–control design. Reliability was assessed in a separate convenience sample.

Results

1,118 responses were included in the overall sample; the mean age of respondents was 46 (standard deviation 15, range 18 – 81) and 150 (13 %) reported a history of skin cancer. In bivariate analysis of 1:2 age-matched cases (n = 149) and controls (n = 298), skin cancer cases were associated with (1) greater CUES prior to first skin cancer diagnosis than controls without skin cancer history (242,074 vs. 205,379, p = 0.003) and (2) less engagement in UV protective behaviors (p < 0.01). In a multivariate analysis of age-matched data, individuals with CUES in the lowest quartile were less likely to develop skin cancer compared to those in the highest quartile. In reliability testing among 19 volunteers, the 2-week intra-class correlation coefficient for CUES was 0.94. We have provided the programming code for this tool as well as the tool itself via open access.

Conclusions

CUES is a useable and comprehensive tool to better estimate lifetime ultraviolet exposure, so that individuals with higher levels of exposure may be identified for counseling on photo-protective measures.

Electronic supplementary material

The online version of this article (doi:10.1186/s12895-016-0038-1) contains supplementary material, which is available to authorized users.

The risks and benefits of sun exposure 2016

Public health authorities in the United States are recommending that men, women and children reduce their exposure to sunlight, based on concerns that this exposure will promote skin cancer. On the other hand, data show that increasing numbers of Americans suffer from vitamin D deficiencies and serious health problems caused by insufficient sun exposure. The body of science concerning the benefits of moderate sun exposure is growing rapidly, and is causing a different perception of sun/UV as it relates to human health. Melanoma and its relationship to sun exposure and sunburn is not adequately addressed in most of the scientific literature. Reports of favorable health outcomes related to adequate serum 25(OH)D concentration or vitamin D supplementation have been inappropriately merged, so that benefits of sun exposure other than production of vitamin D are not adequately described. This review of recent studies and their analyses consider the risks and benefits of sun exposure which indicate that insufficient sun exposure is an emerging public health problem. This review considers the studies that have shown a wide range health benefits from sun/UV exposure. These benefits include among others various types of cancer, cardiovascular disease, Alzheimer disease/dementia, myopia and macular degeneration, diabetes and multiple sclerosis. The message of sun avoidance must be changed to acceptance of non-burning sun exposure sufficient to achieve serum 25(OH)D concentration of 30 ng/mL or higher in the sunny season and the general benefits of UV exposure beyond those of vitamin D.

Risk factors for keratinocyte skin cancer in patients diagnosed with melanoma, a large retrospective study

BACKGROUND

Melanoma survivors are at an increased risk of developing other malignancies, including keratinocyte skin cancer (KSC). While it is known that many risk factors for melanoma also impact risk of KSC in the general population, no previous study has investigated risk factors for KSC development in melanoma patients.

OBJECTIVE

We assessed associations of personal and clinical characteristics, including skin phenotype and variations in the melanocortin 1 receptor (MC1R) gene, with KSC risk in melanoma patients.

PATIENTS AND METHODS

We used prospective follow-up information on 1200 patients treated for melanoma at the Instituto Valenciano de Oncología, Spain, between 2000 and 2011. We computed hazard ratios and 95% confidence intervals (CIs) for the association of clinical, personal and genetic characteristics with risk of KSC, squamous cell carcinoma (SCC), or basal cell carcinoma (BCC) from Cox proportional hazard models. Five-year cumulative incidence based on competing risk models of SCC, BCC or KSC overall was computed using multivariate subdistribution hazard models. To assess predictive performance of the models, we computed areas under the receiver-operating characteristic curves (AUCs, discriminatory power) using cross-validation.

RESULTS

Median follow-up was 57.2 months; a KSC was detected in 163 patients (13.6%). In multivariable Cox models, age, sex, sunburns, chronic sun exposure, past personal history of non-melanoma skin cancer or other non-cutaneous neoplasia, and the MC1R variants p.D294H and p.R163Q were significantly associated with KSC risk. A cumulative incidence model including age, sex, personal history of KSC, and of other non-cutaneous neoplasia had an AUC of 0.76 (95% CI: 0.71-0.80). When p.D294H and p.R163Q variants were added to the model, the AUC increased to 0.81 (95% CI: 0.77-0.84) (p-value for difference <0.0001).

CONCLUSIONS

In addition to age, sex, skin characteristics, and sun exposure, p.R163Q and p.D294H MC1R variants significantly increased KSC risk among melanoma patients. Our findings may help identify patients who could benefit most from preventive measures.

Rationale, design, samples, and baseline sun protection in a randomized trial on a skin cancer prevention intervention in resort environments

INTRODUCTION

Exposure to solar ultraviolet radiation during recreation is a risk factor for skin cancer. A trial evaluated an intervention to promote advanced sun protection (sunscreen pre-application/reapplication; protective hats and clothing; use of shade) during vacations.

MATERIALS AND METHODS

Adult visitors to hotels/resorts with outdoor recreation (i.e., vacationers) participated in a group-randomized pretest-posttest controlled quasi-experimental design in 2012-14. Hotels/resorts were pair-matched and randomly assigned to the intervention or untreated control group. Sun. protection (e.g., clothing, hats, shade and sunscreen) was measured in cross-sectional samples by observation and a face-to-face intercept survey during two-day visits.

RESULTS

Initially, 41 hotel/resorts (11%) participated but 4 dropped out before posttest. Hotel/resorts were diverse (employees=30 to 900; latitude=24° 78' N to 50° 52' N; elevation=2ft. to 9726ft. above sea level), and had a variety of outdoor venues (beaches/pools, court/lawn games, golf courses, common areas, and chairlifts). At pretest, 4347 vacationers were observed and 3531 surveyed. More females were surveyed (61%) than observed (50%). Vacationers were mostly 35-60years old, highly educated (college education=68%) and non-Hispanic white (93%), with high-risk skin types (22%). Vacationers reported covering 60% of their skin with clothing. Also, 40% of vacationers used shade; 60% applied sunscreen; and 42% had been sunburned.

CONCLUSIONS

The trial faced challenges recruiting resorts but result showed that the large, multi-state sample of vacationers were at high risk for solar UV exposure.

Relationship between arsenic-containing drinking water and skin cancers in the arseniasis endemic areas in Taiwan

Artesian well-water had high concentrations of arsenic that led to the well-known black foot disease in Taiwan around the 1950s, and the associated cancers including skin cancer, bladder cancers and lung cancers. We sought to estimate the standardized morbidity ratio (SMR) and age-standardized incidence rate (ASIR) of cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) in the black foot disease endemic areas (BFDEA) in Taiwan. A nationwide retrospective population-based survey was done with the data from the National Taiwan Cancer Registry Center between 1979 and 2007. Among the 29-year period, there were 11 191 cases with SCC and 13 684 cases with BCC diagnosed pathologically. The incidence rates were 4-6-fold higher for SCC and 3-4-fold higher for BCC in the BFDEA compared with the rest of Taiwan. The SMR decreased after stopping arsenic-containing well-water drinking in the 1970s. The arsenic level in the drinking water, amount of contaminated water intake, occupation and sun-exposure time were not documented. This is the first nationwide, population-based study that shows the relationship between arsenic intoxication and non-melanoma skin cancers (SCC and BCC) through comparing the data in people living in the BFDEA and non-BFDEA in Taiwan.

MC1R gene variants and non-melanoma skin cancer: a pooled-analysis from the M-SKIP project

BACKGROUND

The melanocortin-1-receptor (MC1R) gene regulates human pigmentation and is highly polymorphic in populations of European origins. The aims of this study were to evaluate the association between MC1R variants and the risk of non-melanoma skin cancer (NMSC), and to investigate whether risk estimates differed by phenotypic characteristics.

METHODS

Data on 3527 NMSC cases and 9391 controls were gathered through the M-SKIP Project, an international pooled-analysis on MC1R, skin cancer and phenotypic characteristics. We calculated summary odds ratios (SOR) with random-effect models, and performed stratified analyses.

RESULTS

Subjects carrying at least one MC1R variant had an increased risk of NMSC overall, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC): SOR (95%CI) were 1.48 (1.24-1.76), 1.39 (1.15-1.69) and 1.61 (1.35-1.91), respectively. All of the investigated variants showed positive associations with NMSC, with consistent significant results obtained for V60L, D84E, V92M, R151C, R160W, R163Q and D294H: SOR (95%CI) ranged from 1.42 (1.19-1.70) for V60L to 2.66 (1.06-6.65) for D84E variant. In stratified analysis, there was no consistent pattern of association between MC1R and NMSC by skin type, but we consistently observed higher SORs for subjects without red hair.

CONCLUSIONS

Our pooled-analysis highlighted a role of MC1R variants in NMSC development and suggested an effect modification by red hair colour phenotype.

Non-melanoma Skin Cancer in Canada Chapter 1: Introduction to the Guidelines

BACKGROUND

Non-melanoma skin cancer (NMSC), including basal and squamous cell carcinoma, represents the most common malignancy.

OBJECTIVE

The aim of this document is to provide guidance to Canadian health care practitioners on NMSC management.

METHODS

After conducting a literature review, the group developed recommendations for prevention, management, and treatment of basal cell carcinomas, squamous cell carcinomas, and actinic keratoses. These tumour types are considered separately in the accompanying articles. The Grading of Recommendations Assessment, Development and Evaluation system was used to assign strength to each recommendation.

RESULTS

This introduction describes the scope and structure of the guidelines and the methods used to develop them. The epidemiology of NMSC is reviewed, as are the pathophysiologic changes occurring with damage to the skin, which lead to the formation of actinic keratoses and invasive squamous or basal cell carcinomas.

CONCLUSIONS

This introduction describes the need for primary prevention and offers an overview of treatment options that are discussed in later chapters of the guidelines.