Predicting keratinocyte carcinoma in patients with actinic keratosis: development and internal validation of a multivariable risk-prediction model

Background: Patients with actinic keratosis (AK) are at increased risk for developing keratinocyte carcinoma (KC) but predictive factors and their risk rates are unknown. Objectives: To develop and internally validate a prediction model to calculate the absolute risk of a first KC in patients with AK. Methods: The risk-prediction model was based on the prospective population-based Rotterdam Study cohort. We hereto analysed the data of participants with at least one AK lesion at cohort baseline using a multivariable Cox proportional hazards model and included 13 a priori defined candidate predictor variables considering phenotypic, genetic and lifestyle risk factors. KCs were identified by linkage of the data with the Dutch Pathology Registry. Results: Of the 1169 AK participants at baseline, 176 (15·1%) developed a KC after a median follow-up of 1·8 years. The final model with significant predictors was obtained after backward stepwise selection and comprised the presence of four to nine AKs [hazard ratio (HR) 1·68, 95% confidence interval (CI) 1·17–2·42], 10 or more AKs (HR 2·44, 95% CI 1·65–3·61), AK localization on the upper extremities (HR 0·75, 95% CI 0·52–1·08) or elsewhere except the head (HR 1·40, 95% CI 0·98–2·01) and coffee consumption (HR 0·92, 95% CI 0·84–1·01). Evaluat

Association between lifetime smoking and cutaneous squamous cell carcinoma:A 2-sample Mendelian randomization study

Background/Purpose: Cutaneous squamous cell carcinoma (cSCC) is one of the most common malignancies worldwide. While several environmental risk factors for cSCC are well established, there is conflicting evidence on cigarette smoking (and its potential causal effect) and cSCC risk. Furthermore, it is unclear if these potential associations represent causal, modifiable risk factors for cSCC development. This study aims to assess the nature of the associations between cigarette smoking traits (smoking initiation, amount smoked, and lifetime smoking exposure) and cSCC risk using two-sample Mendelian randomization analyses. Methods: Genetic instruments, based on common genetic variants associated with cigarette smoking traits (P &lt; 5 × 10−8), were derived from published genome-wide association studies (GWASs). For cSCC, we used GWAS summary statistics from the Kaiser Permanente GERA cohort (7701 cSCC cases and 60,167 controls; all non-Hispanic Whites). Results: We found modest evidence that genetically determined lifetime smoking was associated with cSCC (inverse-variance weighted method: OR[95% CI] = 1.47[1.09-1.98]; P =.012), suggesting it may be a causal risk factor for cSCC. We did not detect any evidence of association between genetically determined smoking initiation or amount smoked and cSCC risk. Conclusion: Study findings highlight the importance of smoking prevention and may support risk-stratified cSCC screening strategies based on carcinogen exposure and other genetic and clinical information.</p

Prevalence of actinic keratosis and skin cancer in a population of Dutch outdoor workers

Background: Outdoor work is associated with high and chronic exposure to solar ultraviolet radiation which might lead to an increased risk of developing skin (pre)malignancies. Prevalence of actinic keratosis (AK), basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (cSCC) and cutaneous melanoma (cM) in Dutch outdoor workers (OW) has not previously been investigated. Objective: This study compares the prevalence of premalignant lesions and skin tumours in OW and matched controls (non-OW). Methods: In a population-based cohort study, prevalence of premalignant lesions and skin tumours was investigated in a group of OW (n = 841) and controls matched 1:1 by age, sex, skin colour and tendency for sunburn. Skin examinations were conducted by physicians and skin cancer history was derived from the nationwide Dutch Pathology Registry. Information on OW was obtained through interviews. Conditional logistic regression models were used to calculate odds ratios (ORs) with 95% confidence intervals (CIs) for associations between OW and BCC, cSCC, cM and (number of) AK. Results: AK was found in 22.7% of OW and 22.9% of non-OW, BCC in 14% of OW and 15.7% of non-OW, cSCC in 4.9% of OW and 3.4% of non-OW, and cM in 1.9% of OW and 2% of non-OW. There was no significant association between OW and premalignant lesions and skin tumours, with exception for developing ≥4 AKs (OR 1.3 [95% CI 1.0–1.78]). Conclusions: This study reveals high prevalence of premalignant lesions and skin tumours in a Dutch population. No association between OW and the occurrence of premalignant lesions and skin tumours was found, however, multiple AKs were more prevalent in OW.</p

Prevalence of actinic keratosis and skin cancer in a population of Dutch outdoor workers

Background: Outdoor work is associated with high and chronic exposure to solar ultraviolet radiation which might lead to an increased risk of developing skin (pre)malignancies. Prevalence of actinic keratosis (AK), basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (cSCC) and cutaneous melanoma (cM) in Dutch outdoor workers (OW) has not previously been investigated. Objective: This study compares the prevalence of premalignant lesions and skin tumours in OW and matched controls (non-OW). Methods: In a population-based cohort study, prevalence of premalignant lesions and skin tumours was investigated in a group of OW (n = 841) and controls matched 1:1 by age, sex, skin colour and tendency for sunburn. Skin examinations were conducted by physicians and skin cancer history was derived from the nationwide Dutch Pathology Registry. Information on OW was obtained through interviews. Conditional logistic regression models were used to calculate odds ratios (ORs) with 95% confidence intervals (CIs) for associations between OW and BCC, cSCC, cM and (number of) AK. Results: AK was found in 22.7% of OW and 22.9% of non-OW, BCC in 14% of OW and 15.7% of non-OW, cSCC in 4.9% of OW and 3.4% of non-OW, and cM in 1.9% of OW and 2% of non-OW. There was no significant association between OW and premalignant lesions and skin tumours, with exception for developing ≥4 AKs (OR 1.3 [95% CI 1.0–1.78]). Conclusions: This study reveals high prevalence of premalignant lesions and skin tumours in a Dutch population. No association between OW and the occurrence of premalignant lesions and skin tumours was found, however, multiple AKs were more prevalent in OW.</p

The Skin and Nose Microbiome and Its Association with Filaggrin Gene Mutations in Pediatric Atopic Dermatitis

BACKGROUND: Interactions between the skin barrier, immune system, and microbiome underlie the development of atopic dermatitis (AD). OBJECTIVE: To investigate the skin and nasal microbiome in relation to filaggrin gene (FLG) mutations. METHODS: A cross-sectional study including 77 children with difficult-to-treat AD. The entire encoding region of FLG was screened for mutations using single molecule molecular inversion probes and next-generation sequencing. Bacterial swabs from the anterior nares, lesional and nonlesional skin were analyzed using 16S rRNA sequencing. For skin samples, additional qPCR was performed for Staphylococcus aureus and Staphylococcus epidermidis. RESULTS: The prevalence of patients with a mutation in FLG was 40%, including 10 different mutations. Analyzing bacterial swabs from all three niches showed a significant effect for both niche and FLG mutation status on the overall microbiome composition. Using a subset analysis to test the effect of FLG mutation status per niche separately did not show a significant association to the microbiome. Shannon diversity and S. aureus abundance were significantly affected by the niche, but not by the presence of an FLG mutation. CONCLUSIONS: Our results suggest only a minor role for FLG mutation status on the overall microbiome, which is rather caused by differences in the present genera than by microbe richness and evenness

The epidemiology of acne vulgaris in a multiethnic adolescent population from Rotterdam, the Netherlands:A cross-sectional study

Background: Although acne is a prevalent multifactorial inflammatory skin condition, few studies were performed in multiethnic populations. Objectives: To study the prevalence and determinants of acne in a multiethnic study at the start of puberty. Methods: This cross-sectional study is embedded in Generation R, a population-based prospective study from Rotterdam, the Netherlands. Three-dimensional facial photos at the center visit in 2016-2019 (of ∼13-year-olds) were used to grade acne severity using the Global Evaluation of the Acne Severity (GEA). Analyses were stratified by biological sex and explored through chi-square tests and multivariable ordinal logistic regression. Results: A total of 4561 children (51% girls) with a median age of 13.5 (IQR 13.3-13.6) were included. The visible acne prevalence (GEA 2-5) for girls vs boys was 62% vs 45% and moderate-to-severe acne (GEA 3-5) 14% vs 9%. Higher puberty stages (adjusted odds ratios: 1.38 [1.20-1.59] and 2.16 [1.86-2.51] for girls and boys, respectively) and darker skin colors V and VI (adjusted odds ratios: 1.90 [1.17-3.08] and 2.43 [1.67-3.56]) were associated with more severe acne in both sexes, and being overweight in boys (adjusted odds ratio: 1.58 [1.15-2.17]). Limitations: Cross-sectional design. Conclusions: Acne prevalence was high at the age of 13 years and was associated with advanced puberty, darker skin color, and weight status.</p

The epidemiology of acne vulgaris in a multiethnic adolescent population from Rotterdam, the Netherlands:A cross-sectional study

Background: Although acne is a prevalent multifactorial inflammatory skin condition, few studies were performed in multiethnic populations. Objectives: To study the prevalence and determinants of acne in a multiethnic study at the start of puberty. Methods: This cross-sectional study is embedded in Generation R, a population-based prospective study from Rotterdam, the Netherlands. Three-dimensional facial photos at the center visit in 2016-2019 (of ∼13-year-olds) were used to grade acne severity using the Global Evaluation of the Acne Severity (GEA). Analyses were stratified by biological sex and explored through chi-square tests and multivariable ordinal logistic regression. Results: A total of 4561 children (51% girls) with a median age of 13.5 (IQR 13.3-13.6) were included. The visible acne prevalence (GEA 2-5) for girls vs boys was 62% vs 45% and moderate-to-severe acne (GEA 3-5) 14% vs 9%. Higher puberty stages (adjusted odds ratios: 1.38 [1.20-1.59] and 2.16 [1.86-2.51] for girls and boys, respectively) and darker skin colors V and VI (adjusted odds ratios: 1.90 [1.17-3.08] and 2.43 [1.67-3.56]) were associated with more severe acne in both sexes, and being overweight in boys (adjusted odds ratio: 1.58 [1.15-2.17]). Limitations: Cross-sectional design. Conclusions: Acne prevalence was high at the age of 13 years and was associated with advanced puberty, darker skin color, and weight status.</p