Single source CARS-based multimodal microscopy system for biological tissue imaging [Invited].

A coherent anti-Stokes Raman scattering (CARS)-based multimodality microscopy system was developed using a single Ti:sapphire femtosecond laser source for biological imaging. It provides three complementary and co-registered imaging modalities: CARS, MPM (multiphoton microscopy), and RCM (reflectance confocal microscopy). The imaging speed is about 1 frame-per-second (fps) with a digital resolution of 1024 × 1024 pixels. This microscopy system can provide clear 2-dimensional and 3-dimensional images of ex-vivo biological tissue samples. Its spectral selection initiates vibrational excitation in lipid cells (approximately 2850 cm-1) using two filters on the pump and Stokes beam paths. The excitation can be tuned over a wide spectral range with adjustable spectral filters. The imaging capability of this CARS-based multimodal microscopy system was demonstrated using porcine fat, murine skin, and murine liver tissue samples.

Incidence and profile of skin cancers in patients following ultraviolet phototherapy without psoralens: A retrospective cohort study.

BACKGROUND: Psoralen + ultraviolet-A (PUVA) is associated with photocarcinogenesis. However, carcinogenic risk with other ultraviolet phototherapies remains unclear. OBJECTIVE: Evaluate whether phototherapy without psoralens increases skin cancer risk. METHODS: Retrospective cohort study of patients treated at a teaching-hospital phototherapy center (1977-2018). Skin cancer records were validated against pathology reports. Age-standardized incidence rates (ASIRs) of skin cancer were evaluated for gender, skin phototype, diagnosis, ultraviolet modality, anatomical site; and compared to provincial population incidence rates (2003). RESULTS: In total, 3506 patients treated with broadband-ultraviolet-B, narrowband-UVB and/or combined UVAB were assessed with a mean follow-up of 7.3 years. Majority of patients had psoriasis (60.9%) or eczema (26.4%). Median number of treatments was 43 (1-3598). Overall, 170 skin cancers (17 melanoma, 33 squamous cell carcinoma and 120 basal cell carcinoma) occurred in 79 patients. Patient-based and tumor-based ASIR of skin cancer was 149 (95% CI: 112-187)/100,000 and 264 (219-309)/100,000 person-years, respectively. There was no significant difference between tumor-based ASIRs for melanoma, squamous cell carcinoma, and basal cell carcinoma compared to the general population; or in phototherapy patients with-psoriasis or eczema; or immunosuppressants. No cumulative dose-response correlation between UVB and skin cancer was seen. LIMITATIONS: Treatment and follow-up duration. CONCLUSION: No increased risk of melanoma and keratinocyte cancer was found with phototherapy.

Baseline Characteristics of Canadian Patients in the Psoriasis Longitudinal Assessment and Registry (PSOLAR).

BACKGROUND: The Psoriasis Longitudinal Assessment and Registry (PSOLAR) is a global, prospective, longitudinal, disease-based registry. It serves as a post-marketing safety commitment with a focus on patients with moderate to severe plaque psoriasis who are candidates for systemic therapy. OBJECTIVES: To describe the baseline disease demographics and clinical characteristics of a Canadian subgroup of participants enrolled in PSOLAR. METHODS: Baseline demographic/disease characteristics, medical histories, and previous psoriasis treatments for Canadian patients in PSOLAR were summarized using descriptive statistics. RESULTS: There were 1896 patients analyzed in the Canadian subgroup at 37 clinical sites, accounting for 15.7% of the global PSOLAR population. Baseline disease and clinical characteristics were as expected for a moderate to severe psoriasis population and were generally similar to the global PSOLAR population. Two distinctions were noted in the Canadian subgroup versus those enrolled globally: a higher proportion of patients were overweight/obese (84.7% vs. 80.4%) and male (61.4% vs. 54.7%). In addition, the Canadian subgroup had numerically higher historical peak disease activity (PGA score 3.35 vs. 3.1) and longer disease duration (22.3 years vs. 17.5 years). Canadian PSOLAR patients reported a variety of comorbidities, including psoriatic arthritis (31.5%), hypertension (34.6%), hyperlipidemia (24.3%), mental illness (24.1%), and inflammatory bowel disease (1.6%). CONCLUSION: The Canadian subgroup of PSOLAR patients was generally similar to those enrolled globally with respect to baseline disease demographics and clinical characteristics. Multiple comorbidities are noted in the Canadian subgroup, underscoring the need for a holistic approach to the treatment of psoriatic patients.

Barriers and Facilitators in the Creation of a Surveillance System for Solar Radiation-Induced Skin Cancers.

Outdoor workers are exposed to many hazards, including solar ultraviolet radiation (UVR). Identifying, reporting, analyzing and tracking the exposures or health outcomes of outdoor workers have not generally been formally considered. This article aims to summarize the best practices/strategies for creating an occupational sun exposure or skin cancer surveillance system for outdoor workers and to understand the key barriers and facilitators to the development of such a system. For the design of a successful occupational safety and health (OSH) surveillance system five occupational surveillance strategies are summarized: exposure registry, disease registry, disease screening/medical surveillance, sentinel event surveillance, and disease surveillance via data linkage. Ten key considerations are identified, including identifying a clear goal, a defined target population and stakeholder involvement, five critical barriers are highlighted including underreporting and funding, and five vital facilitators are recognized including communication/collaboration and a simple reporting process.

Tailored Sun Safety Messages for Outdoor Workers.

Background: Messaging surrounding skin cancer prevention has previously focused on the general public and emphasized how or when activities should be undertaken to reduce solar ultraviolet radiation (UVR) exposure. Generic messages may not be applicable to all settings, and should be tailored to protect unique and/or highly susceptible subpopulations, such as outdoor workers. The primary objective of this study was to develop a set of tailored, practical, harm-reducing sun safety messages that will better support outdoor workers and their employers in reducing the risk of solar UVR exposure and UVR-related occupational illnesses. Methods: We adapted a core set of sun safety messages previously developed for the general population to be more applicable and actionable by outdoor workers and their employers. This study used an integrated knowledge translation approach and a modified Delphi method (which uses a survey-based consensus process) to tailor the established set of sun safety messages for use for outdoor worker populations. Results: The tailored messages were created with a consideration for what is feasible for outdoor workers, and provide users with key facts, recommendations, and tips related to preventing skin cancer, eye damage, and heat stress, specifically when working outdoors. Conclusion: The resulting tailored messages are a set of evidence-based, expert- approved, and stakeholder-workshopped messages that can be used in a variety of work settings as part of an exposure control plan for employers with outdoor workers.

Follow-up of Patients With Keratinocyte Carcinoma: A Systematic Review of Clinical Practice Guidelines.

Importance: Patients treated for cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), collectively called keratinocyte carcinoma (KC), are at risk for recurrence, metastasis, and additional primary cutaneous malignant neoplasms. It is unclear how often patients should be seen for follow-up skin examination after initial treatment of KC. Objective: To summarize the recommendations and evaluate the methodological quality of clinical practice guidelines for dermatologic follow-up of patients with BCC and invasive SCC. Evidence Review: PubMed, MEDLINE, and Embase were searched for relevant articles published from January 2010 to March 2022. Search terms included guideline, squamous cell carcinoma, and basal cell carcinoma. National or international guidelines containing recommendations for follow-up frequency after a diagnosis of localized cutaneous KC were included. Quality was assessed using the 6 domains of the Appraisal of Guidelines Research and Evaluation II (AGREE II) tool: (1) scope and purpose; (2) stakeholder development; (3) rigor of development; (4) clarity of presentation; (5) applicability; and (6) editorial independence. The Preferred Reporting Items for Systematic Review and Meta-analysis Protocols (PRISMA-P) was used to guide study reporting. Findings: Among the 14 guidelines meeting eligibility criteria, there was little consensus on the appropriate follow-up frequency after initial KC treatment. Overall duration of follow-up ranged from a single posttreatment visit to lifelong surveillance. Most guidelines stratified their recommendations by recurrence risk. For low-risk BCC and guidelines that did not stratify by risk, follow-up recommendations ranged from every 6 to 12 months. For high-risk BCC, 1 guideline suggested follow-up every 3 months, while 4 recommended every 6 months. For low-risk SCC, 5 guidelines recommended annual follow-up; 3 guidelines, every 6 months; and 1 guideline, every 3 months. For high-risk SCC, recommendations included a range of follow-up frequencies, spanning every 3 months (n = 5 guidelines), 4 months (n = 1), 6 months (n = 6), or annually (n = 4). One guideline did not use risk stratification and recommended annual screening. The highest scoring AGREE II domain was "scope and purpose," which assessed the guideline's overall objectives, and the lowest scoring was "applicability," which assessed barriers and facilitators to implementation. Conclusions and Relevance: The findings of this systemic review highlight variations in follow-up recommendations for patients after initial treatment for KC. Randomized clinical trials are needed to define an optimal follow-up regimen.

Tralokinumab Plus Topical Corticosteroids as Needed Provides Progressive and Sustained Efficacy in Adults with Moderate-to-Severe Atopic Dermatitis Over a 32-Week Period: An ECZTRA 3 Post Hoc Analysis.

BACKGROUND: The efficacy and safety of tralokinumab, a fully human monoclonal antibody that specifically neutralizes interleukin-13, plus topical corticosteroids (TCS) as needed were evaluated over 32 weeks in the phase III ECZTRA 3 trial. Significantly more tralokinumab- versus placebo-treated patients achieved the primary endpoints of Investigator's Global Assessment (IGA) score of 0/1 and 75% improvement in Eczema Area and Severity Index (EASI-75) and all confirmatory endpoints at Week 16. OBJECTIVE: This post hoc analysis investigated the impact of tralokinumab plus TCS on atopic dermatitis (AD) severity, symptoms, and health-related quality of life (QoL) over the entire 32-week treatment period of ECZTRA 3, including all patients initiated on tralokinumab irrespective of the response achieved at Week 16. METHODS: Patients were randomized 2:1 to receive subcutaneous tralokinumab 300 mg or placebo every 2 weeks (q2w) with TCS as needed for an initial 16 weeks. At Week 16, patients who achieved the clinical response criteria (IGA 0/1 and/or EASI-75) with tralokinumab were re-randomized 1:1 to tralokinumab q2w or every 4 weeks (q4w), with TCS as needed, for another 16 weeks. Patients not achieving the clinical response criteria with tralokinumab received tralokinumab q2w plus TCS from Week 16. All patients randomized to tralokinumab in the initial treatment period were pooled for this analysis, irrespective of response at Week 16 or dosing regimen beyond Week 16. RESULTS: Continued tralokinumab (q2w, N = 164; q4w, N = 69) plus TCS treatment provided progressive improvements from Week 16 onwards in AD signs, with 70.2% (177/252) of patients achieving EASI-75 and 50.4% (127/252) achieving EASI-90 at Week 32. Improvements in patient-reported outcomes were observed within the first few weeks of tralokinumab q2w plus TCS treatment and were sustained throughout the 32-week period. At Week 32, patients initiated on tralokinumab q2w plus TCS achieved a relative improvement versus baseline of 70.8% (standard error (SE), 2.4) in eczema-related sleep interference numeric rating scale (NRS) and 66.8% (SE, 3.1) in Dermatology Life Quality Index (DLQI). Mean TCS use during Weeks 16-32 ranged from 9.2 to 13.6 g (SE, 1.2-2.0) q2w. Most patients (89.9% (222/247)) initiated on tralokinumab q2w plus TCS achieved a meaningful improvement in at least one of the three disease domains, including AD signs (EASI-50), symptoms (pruritus NRS improvement ≥ 3), and QoL (DLQI improvement ≥ 4) at Week 16. Of patients initiated on tralokinumab q2w plus TCS, 53.4% (132/247) achieved a clinically meaningful improvement in all three domains at Week 16 (vs. placebo, 28.5% (35/123); p < 0.001). CONCLUSIONS: Continued tralokinumab treatment plus TCS as needed provides progressive and sustained improvements in AD signs, symptoms, and health-related QoL over 32 weeks. CLINICAL TRIAL REGISTRATION: NCT03363854; study start date: 22 February 2018; primary completion date: 8 March 2019; study completion date: 26 September 2019.

Atopic dermatitis (AD) is a chronic inflammatory disease that causes excessively dry and itchy skin that can negatively impact sleep and overall quality of life for patients. Topical corticosteroids (TCS) are the most common medication used for AD, but they are not able to control the most severe cases. Tralokinumab is a treatment injected under the skin that targets an immune messenger protein called interleukin 13, which plays a key role in driving the signs and symptoms of AD. The ECZTRA 3 clinical trial, funded by LEO Pharma, compared the use of TCS as needed with either tralokinumab or placebo in over 350 adult patients with moderate-to-severe AD over a 32-week period. After 16 weeks, more patients taking tralokinumab plus TCS had clear or almost clear skin compared with patients taking placebo plus TCS. Patients taking tralokinumab also used less TCS than patients taking placebo. In new analyses presented here, we found that the proportion of patients with clear or almost clear skin continued to increase with on-going treatment from Week 16 to Week 32. Tralokinumab plus TCS treatment also led to clinically meaningful improvements in outcomes important to patients, including itch, sleep, and quality of life. Improvements occurred early, within the first few weeks of therapy, and lasted through Week 32. Our assessment of multiple outcomes over time clearly demonstrates the positive impact of tralokinumab on different aspects of AD.

Polarization memory rate as a metric to differentiate benign and malignant tissues.

Non-invasive optical methods for cancer diagnostics, such as microscopy, spectroscopy, and polarimetry, are rapidly advancing. In this respect, finding new and powerful optical metrics is an indispensable task. Here we introduce polarization memory rate (PMR) as a sensitive metric for optical cancer diagnostics. PMR characterizes the preservation of circularly polarized light relative to linearly polarized light as light propagates in a medium. We hypothesize that because of well-known indicators associated with the morphological changes of cancer cells, like an enlarged nucleus size and higher chromatin density, PMR should be greater for cancerous than for the non-cancerous tissues. A thorough literature review reveals how this difference arises from the anomalous depolarization behaviour of many biological tissues. In physical terms, though most biological tissue primarily exhibits Mie scattering, it typically exhibits Rayleigh depolarization. However, in cancerous tissue the Mie depolarization regime becomes more prominent than Rayleigh. Experimental evidence of this metric is found in a preliminary clinical study using a novel Stokes polarimetry probe. We conducted in vivo measurements of 20 benign, 28 malignant and 59 normal skin sites with a 660 nm laser diode. The median PMR values for cancer vs non-cancer are significantly higher for cancer which supports our hypothesis. The reported fundamental differences in depolarization may persist for other types of cancer and create a conceptual basis for further developments in polarimetry applications for cancer detection.

Treatment Guidelines for Atopic Dermatitis Since the Approval of Dupilumab: A Systematic Review and Quality Appraisal Using AGREE-II.

Introduction: Since its approval for adults with moderate-to-severe atopic dermatitis (AD) in 2017, dupilumab has been incorporated into clinical practice guidelines (CPGs). However, recommendations differ internationally, and the quality assessment of their development is unclear. Objective: We aimed to systematically review and appraise the quality of CPGs for adult AD reported since 2017 and map the recommendations for dupilumab initiation relative to conventional systemic therapy (CST). Materials and Methods: A literature search was conducted in June 2020 in MEDLINE, EMBASE, SCOPUS, and CINAHL. Twelve CPGs were retrieved. Methodological quality was assessed using the validated Appraisal of Guidelines for Research & Evaluation II tool (AGREE-II). Recommendations were extracted and compared. Results: AGREE-II median scores per domain of the CPGs were (%, r = range): scope/purpose, 78% (50-96); stakeholder involvement, 54% (28-85); rigor of development, 39% (21-63); clarity of presentation, 85% (69-100); applicability, 27% (6-51); and editorial independence, 76% (42-100). Neither met the threshold of 70% quality criteria for rigor of development nor the applicability domains. Three CPGs met the criteria for recommendation without modification. CPGs' approach to dupilumab initiation was as follows: second line, preferred over CST and nbUVB (n = 1/12 CPG); second line, equivalent to CST or nbUVB (n = 3/12 CPGs); third line, after nbUVB or CST (n = 5/12 CPGs); and fourth line after nbUVB and CST (n = 2/12). No consensus was reached for n = 1/12 CPG. Conclusion and Relevance: Dupilumab is now incorporated into CPGs for adult AD. These CPGs exhibited good quality in scope/purpose, clarity, and editorial independence domains. However, none met AGREE-II criteria for methodological rigor/applicability. Gaps were found in mechanisms for updates, facilitators/barriers, resource implications, and stakeholder involvement. Only n = 3/12 CPGs met quality criteria for recommendation without modifications. Of these, two favored a conservative sequential approach for the initiation of dupilumab relative to CST, while one did not reach consensus. Our findings highlight divergent recommendations AD treatment, underlining a need to incorporate quality criteria into future guideline development.

Assessment of sun-safety education behavior via spectrophotometric evaluation: A preliminary study.

BACKGROUND: Biases inherent in self-assessment of sun exposure and sun-safe behavior may lead to inaccurate conclusions about the effectiveness of sun-safety educational programs. OBJECTIVES: We aimed to compare self-reports to objective measures of sun exposure, when examining the effectiveness of passive versus active educational interventions. METHODS: From May to June 2018, 73 participants recruited at a dermatology clinic were sequentially assigned to receive sun-safety education through one of 3 modes: interactive online module, video, or no education. A baseline Sun Exposure and Behavior Inventory (SEBI) questionnaire was administered, and spectrophotometric measurements of sun-exposed and sun-protected areas were taken and reported in the CIE L*a*b* color space. Participants were followed 4-8 and 16 weeks after the initial visit where the SEBI was re-administered, and serial measurements of skin color were taken. The change in SEBI scores and L*a*b values, as calculated by the individual typology angle (ITA°), was analyzed. RESULTS: There was a significant increase in skin darkening in all the groups at 4-8 and 16 weeks follow-up. There was no statistically significant difference between the groups in the magnitude of color change. However, subjectively at 4-8 weeks post-intervention, participants in the interactive module and video groups had significantly improved self-reported SEBI scores compared to control (p < .05, Kruskal-Wallis). By 16 weeks, only the interactive module group showed significant improvement in SEBI scores compared to control (p < .05, ANOVA). CONCLUSION: In determining the effectiveness of sun-safety programs, spectrophotometric evaluation of sun-induced skin pigmentation can allow for a more complete evaluation of self-reported sun exposure and sun-protective behavior.

Constructing a portable optical polarimetry probe for in-vivo skin cancer detection.

SIGNIFICANCE: Management of skin cancer worldwide is often a challenge of scale, in that the number of potential cases presented outweighs the resources available to detect and treat skin cancer. AIM: This project aims to develop a polarimetry probe to create an accessible skin cancer detection tool. APPROACH: An optical probe was developed to perform bulk tissue Stokes polarimetry, a technique in which a laser of known polarization illuminates a target, and the altered polarization state of the backscattered light is measured. Typically, measuring a polarization state requires four sequential measurements with different orientations of polarization filters; however, this probe contains four spatially separated detectors to take four measurements in one shot. The probe was designed to perform at a lower cost and higher speed than conventional polarimetry methods. The probe uses photodiodes and linear and circular film polarizing filters as detectors, and a low-coherence laser diode as its illumination source. The probe design takes advantage of the statistical uniformity of the polarization speckle field formed at the detection area. RESULTS: Tests of each probe component, and the complete system put together, were performed to evaluate error and confirm the probe's performance despite its low-cost components. This probe's potential is demonstrated in a pilot clinical study on 71 skin lesions. The degree of polarization was found to be a factor by which malignant melanoma could be separated from other types of skin lesions.

Pregnancy Outcomes in Women With Moderate-to-Severe Psoriasis From the Psoriasis Longitudinal Assessment and Registry (PSOLAR).

Importance: Prospective data are limited on pregnancy outcomes among women with psoriasis who may be receiving biologic or conventional systemic therapy. Objective: To report pregnancy outcomes observed in the Psoriasis Longitudinal Assessment and Registry (PSOLAR). Design, Setting, and Participants: This cohort study used data from PSOLAR, a multicenter, disease-based, observational registry evaluating long-term safety and clinical outcomes for patients receiving or eligible to receive treatment for psoriasis with biologics and/or conventional systemic therapies. Of 12 090 enrollees, 5456 were women (45.1%), and 2224 women were of childbearing age (18-45 years). Participants had a total of 12 929 patient-years of follow-up (median, 7.2 [range, 3.3-8.0] years per patient). Data were collected from June 20, 2007, to August 23, 2019, and analyzed from April 23 to June 23, 2020. Exposures: Exposure to biologics within the prenatal period (≤1 year before birth or ≤6 months before spontaneous abortion) or at any other time. Main Outcomes and Measures: Descriptive summaries of pregnancies and pregnancy-related outcomes were self-reported in PSOLAR, including births, stillbirths, spontaneous abortions, and elective terminations. Live birth characteristics collected in PSOLAR include whether a birth was full-term (≥37 weeks) or premature (<37 weeks) and whether neonatal adverse events or congenital anomalies occurred. Results: A total of 298 pregnancies occurred among 220 women (mean [SD] age, 27.8 [5.2] years), and the general fertility rate was 18.9 per 1000 women aged 18 to 45 years. Of the 298 pregnancies, 244 (81.9%) resulted in birth, 41 (13.8%) ended in spontaneous abortion, and 13 (4.4%) were electively terminated. Gestational age was available for 243 births; 221 infants (90.9%) were full-term, and 22 (9.1%) were born prematurely. Birth outcomes included 231 healthy newborns, 10 infants with a neonatal problem, 2 infants with a congenital anomaly, and 1 stillbirth. Of the 298 pregnancies, 252 were associated with biologic exposure before or during pregnancy. Pregnancy outcomes for women exposed to biologics were similar to those for women exposed to nonbiologics. Among women who became pregnant, mean (SD) age at the time of pregnancy outcome was 30.9 (4.8) years; at enrollment into the registry, 74 of 219 (33.8%) had obesity, and 121 of 220 (55.0%) were past or current smokers. Conclusions and Relevance: The findings of this cohort study suggest that pregnancy outcomes in PSOLAR have remained consistent with previous reports. Overall and live birth outcomes were similar to those for the general population.

Sun Protection Use at Work and Leisure by Outdoor Workers in Alberta, Canada.

OBJECTIVE: To assess the prevalence and determinants of sun protection behaviours among outdoors workers at work and leisure in Alberta, Canada. METHODS: We collected outdoor workers' demographics, skin cancer risk factors, job information, and sun habits at work and leisure using self-completed questionnaires. For both settings, we compared use of specific behaviours and modelled determinants of sun protection behaviour scores. RESULTS: At work, wearing a sleeved shirt (81% often/always) and hat (73%) were most prevalent, while seeking shade (12%) and applying sunscreen (36%) were least prevalent. Workers had higher sun protection scores at work than leisure. Hours spent outdoors was a strong determinant for both models. Additional leisure model predictors were eye colour, sex, skin type, and job group. CONCLUSIONS: Differences in behaviours across settings were observed and should be considered when developing solar UVR exposure reduction initiatives.

Solar ultraviolet radiation exposure among outdoor workers in Alberta, Canada.

BACKGROUND: Outdoor workers are at risk of prolonged and high solar ultraviolet radiation (UVR) exposure, which is known to cause skin cancer. The objectives of this study were to characterize the UVR exposure levels of outdoor workers in Alberta, Canada, and to investigate what factors may contribute to their exposure. METHODS: This study collected objective solar UVR measurements from outdoor workers primarily in Alberta during the summer of 2019. Workers were recruited via the management or health and safety teams from building trade unions and employers. Calibrated, electronic UVR dosimeters were worn by workers on their hardhats, wrists, or lapels for five working days. Data on workers' demographics, jobs, sun protection behaviors, and personal risk factors were collected using questionnaires, and meteorological data for each sampling day were noted. Mean daily exposure measured as the standard erythemal dose (SED) was calculated and compared to the international occupational exposure limit guideline (1.3 SED). Marginal models were developed to evaluate potential determinants of occupational solar UVR exposure. RESULTS: In total, 883 measurements were collected from 179 workers. On average, workerswere exposed to 1.93 SED (range: 0.03-16.63 SED) per day. Just under half of workers (45%) were exposed to levels exceeding the international exposure limit guideline. In the bivariate analyses, landscape and maintenance workers, as well as trade and recreation workers, had the highest levels of exposure (average: 2.64 and 1.84 SED, respectively). Regional variations were observed, with the "other" cities/regions (outside of Edmonton and Calgary) experiencing the highest average levels (2.60 SED). Workers who placed the dosimeters on their hardhats experienced higher levels compared to the other groups. Exposure was highest on sunny and mixed days. Education, trade, city, dosimeter placement, forecast, hair colour, and number of hours outside were included in the final exposure model, of which trade, dosimeter placement, forecast, and number of hours outside at work were statistically significant. CONCLUSIONS: Exposure to elevated solar UVR levels is common among outdoor workers in Alberta. The study findings can help inform future monitoring studies and exposure reduction initiatives aimed at protecting workers.

Strategic Task and Break Timing to Reduce Ultraviolet Radiation Exposure in Outdoor Workers.

Objectives: Public health messaging about sun avoidance strategies is often not practical for outdoor workers. The objective of this study was to use personal monitoring data to determine when peak UVR exposure occurs for outdoor workers, estimate how much UVR could be reduced by altering the timing of shady tasks or breaks during peak exposure times, and descriptively compare these to peak periods of ambient UVR. Ultimately, we aim to provide evidence-based sun avoidance recommendations for outdoor workers in British Columbia, Canada. Methods: UVR exposure data [standard erythemal dose (SED)] were collected during the 2013 summer months in Vancouver, using personal electronic dosimeters that sampled once per minute for an average of 4.4 working days (range: 1-7 days). Mixed-effect models were used to estimate the 60-, 30-, and 15-min time intervals at which maximum exposure occurred for the months of July and August. Using these time intervals, UVR exposure during peak periods was summarized as SED and as a percentage of the total daily exposure. Ambient UVR was also collected using data from the nearest Brewer spectrophotometer station and parallel analyses were conducted. Results: There were 73 workers and 321 participant-days available for analysis. Models indicated that periods of maximum exposure for 15-, 30-, and 60-min intervals began at 12:28, 12:17 pm, and 11:52 am, respectively, for sunny days in July. These periods were similar in August. The median exposure during these time periods and the potential for reducing UVR was 0.03 SED (2.8% potential daily exposure reduction), 0.09 SED (7.1%), and 0.18 SED (15.9%), respectively. However, there was a large range in exposure estimates as some workers experienced up to 84.8% of their exposure in the peak 60-min interval. Conclusion: Skin cancer prevention messaging does not include practical messages for outdoor workers and providing times of peak UVR help to identify times when the greatest reductions in exposure can occur. Prevention measures including shady breaks, increased sun protection, and task reorganization during these peak times are recommended during these peak times to reduce UVR exposure among those at highest risk.

Non-Melanoma Skin Cancer Risk Among Patients in the Psoriasis Longitudinal Assessment and Registry (PSOLAR)

To the Editor: Patients with psoriasis are at increased risk of developing non melanoma skin cancer (NMSC), including squamous cell carcinoma (SCC) and basal cell carcinoma (BCC).1,2 The risk is especially elevated among those who previously received systemic treatment or phototherapy.2 Systemic treatments, including biologic therapies and methotrexate (MTX), are effective in managing immune-mediated diseases; however, they may increase susceptibility to NMSC due to immunosuppression or other factors.3

Relationship between sun safety behaviours and modifiable lifestyle cancer risk factors and vitamin D levels.

BACKGROUND: Sun exposure is the most important environmental risk factor for causing skin cancer. PURPOSE: This study examines the relationship between sun protection behaviours and modifiable lifestyle risk factors for other cancers as well as vitamin D levels. METHODS: Cross-sectional data were analysed from two large national health surveys (n = 31, 445 and n = 5604). Sun exposure and protection were characterized by the presence of sunburn, duration of sun exposure, frequency of seeking shade, frequency of wearing a hat and frequency of wearing sunscreen. Using Statistical Analysis System (SAS) software 9.3.1, multivariate logistic regression models were compiled. RESULTS: Unhealthy behaviour practices were associated with sunburns or infrequent sun protection behaviour, such as cigarette consumption (either current or former smokers), second-hand smoke exposure, not having a regular doctor, higher level of alcohol consumption, street drug usage and low levels of fruit/vegetable consumption. Approximately one-quarter of individuals had less than the recommended value of serum vitamin D levels (<50 nmol/L), despite 39.2% of these individuals reporting ≥1 hour of sun exposure. CONCLUSION: Modifiable lifestyle risk factors for other cancers are correlated with infrequently practicing sun protection behaviours for skin cancer prevention. Therefore, cancer prevention campaigns can aim to target all these risk factors associated with different cancers. Sun exposure is not a reliable source to obtain recommended vitamin D levels and that other sources (eg. fish, egg yolk, fortified drinks and supplements) are a safer and more reliable option.

Site-specific variations in cutaneous autofluorescence revealed by excitation-emission matrix spectroscopy.

BACKGROUND AND PURPOSE: Although cutaneous autofluorescence has been utilized for evaluation of skin conditions, there is a paucity of data on normal human skin autofluorescence and its dependence on anatomical site. The objective of this study is to use excitation-emission matrix spectroscopy to quantify and characterize skin autofluorescence at different body sites. METHODS: Ten anatomical sites from 30 healthy volunteers were measured with a double-grating excitation-emission matrix spectrofluorometer. RESULTS: For the 10 body sites evaluated, there were four overall patterns of autofluorescence: skin from the head and neck exhibits high superficial and low bilayer fluorescence; the dorsal forearm and dorsal hand have both low superficial and bilayer fluorescence; the upper inner arm and back have high superficial and intermediate bilayer fluorescence; while the palm and thumbnail have both high superficial and bilayer fluorescence. The corresponding fluorescence excitation-emission peaks for these patterns were as follows: head and neck, 3 peaks at 290-300/330-350, 360-380/460-485, and 380-420/610-630 nm; dorsal forearm and dorsal hand, 2 peaks around 295-300/345-360 and 385-395/460-485 nm; upper inner arm and back, 3 peaks around 295-300/335-355, 335-340/390-410, and 375-390/455-480 nm; palm and thumbnail, 3 peaks around 285-300/345-355, 335-345/390-410, and 365-390/450-480 nm. CONCLUSION: Cutaneous fluorescence varies in distinct patterns according to anatomical site, due to the component fluorophores present, skin thickness, and the degree of melanization and long term sun exposure. These EEM patterns for normal skin should be accounted for when interpreting fluorescence signals from disease states and can also be used to guide the selection of optimal wavebands when applying this optical modality.