Trajectories of Nevus Development From Age 3 to 16 Years in the Colorado Kids Sun Care Program Cohort

Addressing Frequently Asked Questions and Dispelling Myths About Melanocytic Nevi in Children

Melanocytic nevi are congenital or acquired benign melanocytic neoplasms. The reason for the appearance of melanocytic nevi is not precisely known. Melanocytic nevi frequently occur in children, constituting a common reason for consultation in pediatric dermatology clinics. In our experience, many parents and caregivers present doubts and fears based more on popular beliefs than on data with valid scientific evidence. This review answers their frequently asked questions, such as the risk of malignancy, the importance of nevi location, the warning signs of malignant transformation, best prevention strategies, and optimal management, based on the most recent scientific evidence available.

Genetically determined cutaneous nevi and risk of cancer

Numerous epidemiologic studies have reported positive associations between higher nevus counts and internal cancers. Whether this association represents a true relationship or is due to bias or confounding by factors associated with both nevus counts and cancer remains unclear. We used germline genetic variants for nevus count to test whether this phenotypic trait is a risk-marker for cancer. We calculated polygenic risk scores (PRS) for nevus counts using individual-level data in the UK Biobank (n = 394 306) and QSkin cohort (n = 17 427). The association between the nevus PRS and each cancer site was assessed using logistic regression adjusted for the effects of age, sex and the first five principal components. In both cohorts, those in the highest nevus PRS quartile had higher risks of melanoma than those in the lowest quartile (UK Biobank odds ratio [OR] 1.42, 95% confidence interval [CI]: 1.29-1.55; QSkin OR 1.58, 95% CI: 1.29-1.94). We also observed increases in risk of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) associated with higher nevus PRS quartiles (BCC UK Biobank OR 1.38, 95% CI: 1.33-1.44; QSkin OR 1.20, 95% CI: 1.05-1.38 and SCC UK Biobank OR 1.41, 95% CI: 1.28-1.55; QSkin OR 1.44, 95% CI: 1.19-1.77). We found no consistent evidence that nevus count PRS were associated with risks of developing internal cancers. We infer that associations between nevus counts and internal cancers reported in earlier observational studies arose because of unmeasured confounding or other biases.

A practical review of dermoscopy for pediatric dermatology part I: Melanocytic growths

The value of dermoscopy in the detection of skin cancer is well established. Less is published on the utility of dermoscopy in the evaluation of pediatric skin disease. Our review (in two parts) aims to serve as an update on pediatric dermoscopy and to provide readers with a practical application for the use of dermoscopy in pediatric dermatology clinics. In part I, we propose a dermoscopy algorithm for pediatric skin disease and melanocytic growths, and in part II, we address vascular growths, common skin infections, and inflammatory conditions for which dermoscopy is valuable.