Hydrogen Peroxide 40% for the Treatment of Seborrheic Keratoses.

OBJECTIVE: Hydrogen peroxide 40% (HP40) was approved by the US Food and Drug Administration for topical treatment of seborrheic keratosis (SK) in December 2017. This article will review phase II and III clinical trials to assess the drug's efficacy, safety, and clinical application. DATA SOURCES: A systematic literature review was performed using the terms "Eskata AND seborrheic keratosis," and "hydrogen peroxide AND seborrheic keratosis" in the OVID MEDLINE, PubMed, Cochrane Library, EMBASE, and Web of Science databases. ClinicalTrials.gov was searched to identify ongoing or nonpublished studies. STUDY SELECTION AND DATA ABSTRACTION: Articles written in English between January 2000 and mid-June 2020 discussing phase II and phase III clinical trials were evaluated. DATA SYNTHESIS: In 2 phase III clinical trials, 4% and 8% of patients treated with HP40 had a Physician Lesion Assessment score of zero for all 4 SKs, respectively, compared with 0% in both vehicle groups at the primary end point of day 106 (P < 0.01; P < 0.0001). RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: HP40, although less effective, has a better safety profile than other treatment options. It should be especially considered for treatment of facial SKs, where it is most efficacious and where other treatment modalities, such as cryotherapy, are more challenging. CONCLUSIONS: HP40 is a new, safe alternative treatment for SKs, although it is expensive and only modestly effective, both of which somewhat limit its overall utility. HP40 is a promising topical alternative, particularly for cosmetically sensitive locations, such as the face.

Striking contiguous depigmentation across the lower limbs in piebaldism and its implications for understanding melanocytic migration and development.

Piebaldism is a rare autosomal dominant disorder of pigmentation that is characterized by variable patches of depigmentation on the face, chest, abdomen, and extremities. We describe two cases of piebaldism, in whom the remarkable asymmetric distribution of the depigmented patches in a connected, contiguous pattern across the legs provides embryologic insights. This finding is not explained by the traditional theory that melanocytic migration only originates in the neural crest and progresses unilaterally down each leg. We propose that our cases, and other similar cases, can be explained by a recent theory of mesodermal melanocyte migration.

In-depth examination of hyperproliferative healing in two breeds of Sus scrofa domesticus commonly used for research.

Background: Wound healing can result in various outcomes, including hypertrophic scar (HTS). Pigs serve as models to study wound healing as their skin shares physiologic similarity with humans. Yorkshire (Yk) and Duroc (Dc) pigs have been used to mimic normal and abnormal wound healing, respectively. The reason behind this differential healing phenotype was explored here. Methods: Excisional wounds were made on Dc and Yk pigs and were sampled and imaged for 98 days. PCR arrays were used to determine differential gene expression. Vancouver Scar Scale (VSS) scores were given. Re-epithelialization was analyzed. H&E, Mason's trichrome, and immunostains were used to determine cellularity, collagen content, and blood vessel density, respectively. Results: Yk wounds heal to a "port wine" HTS, resembling scarring in Fitzpatrick skin types (FST) I-III. Dc wounds heal to a dyspigmented, non-pliable HTS, resembling scarring in FST IV-VI. Gene expression during wound healing was differentially regulated versus uninjured skin in 40/80 genes, 15 of which differed between breeds. Yk scars had a higher VSS score at all time points. Yk and Dc wounds had equivalent re-epithelialization, collagen disorganization, and blood vessel density. Conclusions: Our findings demonstrate that Dc and Yk pigs can produce HTS. Wound creation and healing were consistent among breeds, and differences in gene expression were not sufficient to explain differences in resulting scar phenotype. Both pig breeds should be used in animal models to investigate novel therapeutics to provide insight into a treatment's effectiveness on various skin types.