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BACKGROUND: KIT mutations are primarily associated with acral and mucosal melanoma, and have been reported to show higher prevalence in chronic sun-damaged (CSD) than non-CSD melanomas. OBJECTIVES: To investigate the prevalence of KIT mutations in melanoma according to subtype, and determine the clinical role of such mutations. MATERIALS & METHODS: We present results from a study of a Spanish population of 492 melanomas, classified according to the latest World Health Organization (WHO) guidelines. We analysed the mutational status of KIT and correlated with different clinical variables related to sun exposure and family history. RESULTS: KIT mutations were significantly more frequent in acral (3/36; 8.3%) and mucosal (4/8; 50%) melanomas than non-acral cutaneous melanomas. No significant difference was observed in KIT mutational status between CSD and non-CSD melanomas. CONCLUSION: Our results suggest that KIT mutations in melanoma tumours are unrelated to the development of nevi or chronic sun damage, but their presence is associated with aggressive melanomas which show ulceration, vascular invasiveness, and increased Breslow thickness. These findings are consistent with those reported by The Cancer Genome Atlas network.

The aim of this study was to evaluate the morphological findings of lipidised dermatofibromas under dermoscopic observation.

Foot eczema is a common complaint encountered by skin allergists.To study a series of patients with foot eczema who underwent patch testing and describe their demographic profile, diagnoses, and the main allergens involved.Cross-sectional observational study of all patients tested with the standard Spanish patch test series at a dermatology department over a period of 13 years (2004-2016). We studied patch test results and definitive diagnoses by comparing different subgroups of patients with foot eczema.Of the 3,265 patients included in the study, 308 (9.4%) had foot eczema, 176 (57.9%) had foot eczema only and 132 (42.1%) had concomitant foot and hand eczema. Positive patch test results were more common in patients with foot eczema only (positivity rate of 61.5% vs. 53.4% for foot and hand eczema). In the subgroup of patients with concomitant foot and hand involvement, patients aged under 18 years had a lower rate of positive results (51.3% vs. 64.6% for patients18 years). Potassium dichromate was the most common allergen with current relevance in all subgroups. The main diagnosis in patients with foot involvement only was allergic contact dermatitis (49.1%). In the subgroup of patients with concomitant hand and foot eczema, the main diagnoses were psoriasis in adults (33.6%) and atopic dermatitis in patients aged under 18 years (60.0%).Patch tests are a very useful diagnostic tool for patients with foot eczema with or without concomitant hand involvement.

Epidemiological associations linking between obstructive sleep apnea and poorer solid malignant tumor outcomes have recently emerged. Putative pathways proposed to explain that these associations have included enhanced hypoxia inducible factor (HIF)-1 alpha and vascular endothelial growth factor (VEGF) cell expression in the tumor and altered immune functions via intermittent hypoxia (IH). Here, we examined relationships between HIF-1 alpha and VEGF expression and nocturnal IH in cutaneous melanoma (CM) tumor samples. Prospectively recruited patients with CM tumor samples were included and underwent overnight polygraphy. General clinical features, apnea-hypopnea index (AHI), desaturation index (DI4%), and CM characteristics were recorded. Histochemical assessments of VEGF and HIF-1 alpha were performed, and the percentage of positive cells (0, < 25, 25-50, 51-75, > 75%) was blindly tabulated for VEGF expression, and as 0, 0-5.9, 6.0-10.0, > 10.0% for HIF-1 alpha expression, respectively. Cases with HIF-1 alpha expression > 6% (high expression) were compared with those < 6%, and VEGF expression > 75% of cells was compared with those with < 75%. 376 patients were included. High expression of VEGF and HIF-1 alpha were seen in 88.8 and 4.2% of samples, respectively. High expression of VEGF was only associated with increasing age. However, high expression of HIF-1 alpha was significantly associated with age, Breslow index, AHI, and DI4%. Logistic regression showed that DI4% [OR 1.03 (95% CI: 1.01-1.06)] and Breslow index [OR 1.28 (95% CI: 1.18-1.46)], but not AHI, remained independently associated with the presence of high HIF-1 alpha expression. Thus, IH emerges as an independent risk factor for higher HIF-1 alpha expression in CM tumors and is inferentially linked to worse clinical CM prognostic indicators.

The use of NGS in clinical practice for precision diagnosis requires a quality starting material. Despite the broadly established use of formalin-fixed paraffin-embedded (FFPE) samples in molecular testing, these usually have low-quality DNA. We established a method to determine the suitability of melanoma FFPE samples for an amplicon-based NGS custom panel analysis. DNA was extracted from unstained melanoma samples and wide local excision samples. Amplicon-based libraries were constructed and tested using time and quality parameters as variables. Time elapsed from sample retrieval >7 years, a quality control value > 5.63 and a DNA integrity value