Metformin is associated with decreased risk of basal cell carcinoma: A whole-population case-control study from Iceland.

Background: Metformin has anticarcinogenic properties and is also known to inhibit the sonic hedgehog pathway, but population-based studies analyzing the potential protective effect for basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are needed.

Objectives: To delineate the association between metformin use and invasive SCC, SCC in situ (SCCis), and BCC.

Methods: A population-based case-control study design was employed using all 6880 patients diagnosed in Iceland between 2003-2017 with first-time BCC, SCCis, or invasive SCC, and 69,620 population controls.

Loss-of-Function Variants in the Tumor-Suppressor Gene Confer Increased Cancer Risk.

The success of genome-wide association studies (GWAS) in identifying common, low-penetrance variant-cancer associations for the past decade is undisputed. However, discovering additional high-penetrance cancer mutations in unknown cancer predisposing genes requires detection of variant-cancer association of ultra-rare coding variants. Consequently, large-scale next-generation sequence data with associated phenotype information are needed.

Association between hydrochlorothiazide and the risk of in situ and invasive squamous cell skin carcinoma and basal cell carcinoma: A population-based case-control study.

Background: Population-based studies analyzing hydrochlorothiazide's (HCTZ's) effect on keratinocyte carcinoma, and particularly invasive squamous cell carcinoma (SCC), are lacking.

Objectives: To characterize the association between HCTZ use and invasive SCC, SCC in situ (SCCis), and basal cell carcinoma (BCC).

Methods: This population-based case-control study included all 6880 patients diagnosed with first-time BCC, SCCis, and invasive SCC between 2003 and 2017 in Iceland and 69,620 population controls.

Autoimmune collagen vascular diseases: Kids are not just little people.

Morphea, dermatomyositis (DM), and discoid lupus erythematosus (DLE) are autoimmune collagen vascular diseases that can present at any age. In all three of these diseases, the tenants of diagnosis and treatment are largely the same in both children and adults, with a few notable differences. Children with morphea are more likely to present with the linear subtype and have a higher incidence of extracutaneous manifestations.

Paired comparison of the sensitivity and specificity of multispectral digital skin lesion analysis and reflectance confocal microscopy in the detection of melanoma in vivo: A cross-sectional study.

Background: Several technologies have been developed to aid dermatologists in the detection of melanoma in vivo including dermoscopy, multispectral digital skin lesion analysis (MDSLA), and reflectance confocal microscopy (RCM). To our knowledge, there have been no studies directly comparing MDSLA and RCM.

Objective: We conducted a repeated measures analysis comparing the sensitivity and specificity of MDSLA and RCM in the detection of melanoma (n = 55 lesions from 36 patients).

A case of recurrent pseudolymphomatous folliculitis: A mimic of cutaneous lymphoma.

Pseudolymphomatous folliculitis is a rare entity. We present a 62-year-old man with a recurrent solitary nodule on his nose requiring multiple excisions. Microscopic examination of the excisions showed a dense lymphocytic infiltrate containing numerous histiocytes and S100+, CD1a+ dendritic cells that surrounded and infiltrated hypertrophic hair follicles.

Pagetoid reticulosis in a 5-year-old boy.

We present a rare case of pagetoid reticulosis arising in a 5-year-old white boy. He had a history of a large chronic erythematous, scaly patch on his left buttock that had shown intermittent partial response to a topical antifungal medication. A punch biopsy specimen revealed dramatic epidermal hyperplasia, with parakeratosis and prominent exocytosis of single and clustered mononuclear cells (Pautrier's microabscesses) into the epidermis.

A neutropenic child with a purple lesion on the thigh.

Zygomycosis is an aggressive infection by an angioinvasive fungus seen in patients with defects in phagocytosis. We describe a neutropenic child with primary cutaneous Rhizopus infection presenting with a bull's-eye appearance. The patient was treated with aggressive surgical debridement along with amphotericin B followed by skin grafting, with full recovery.