Association of Indoor Tanning Exposure With Age at Melanoma Diagnosis and BRAF V600E Mutations.

There is limited information on how indoor tanning promotes melanoma development. We investigated indoor tanning use in patients with melanomas in sun-exposed skin and studied the clinicopathological and molecular characteristics in relation to indoor tanning exposure. Patients from a multidisciplinary clinic for cutaneous cancers completed standardized questionnaires on risk factors for melanoma as a component of medical history at their initial consultations. For this study, we included patients from December 2013 to May 2015. The 114 patients who reported indoor tanning exposure were younger at diagnosis than the 222 patients who did not (51.5 vs 64.0 years, two-sided P < .001). BRAF V600E genotype was more prevalent in ever-users than in nonusers (42.9% vs 28.3%, two-sided P = .04) and higher in ever-users who initiated indoor tanning prior to age 25 years compared with age 25 years or older (62.2% vs 31.1%, two-sided P = .003). There were more melanomas in intermittently sun-exposed skin in ever-users than nonusers (65.7% vs 51.9%, respectively, two-sided P = .02). Our data suggest indoor tanning may promote melanomas that arise in skin with low-chronic sun-induced damage through BRAF V600E-mediated melanomagenesis.

Quantitative and qualitative changes of von Willebrand factor and their impact on mortality in patients with end-stage kidney disease.

von Willebrand factor (vWF) antigen levels are elevated in patients with end-stage kidney disease (ESKD). We determined the quantitative and qualitative abnormalities of vWF and factors influencing vWF proteolysis in participants with ESKD compared with age-matched controls and determined the association between abnormalities in vWF and mortality over 4 years of follow-up. vWF : Ag and von Willebrand factor propeptide (vWFpp) levels, vWF functional activity (vWF :RCo), vWF multimer profiles, ADAMTS-13, thrombospondin 1 (TSP-1), and interleukin 6 (IL-6) were evaluated before and after a single hemodialysis treatment in 55 individuals with vascular disease and an age-matched group of controls (n = 21). vWF : Ag and vWF activity were significantly higher in the ESKD patients and levels increased further following the dialysis procedure. The percentage of high molecular weight multimers (%HMWMs) was significantly elevated in the ESKD patients compared with controls. TSP-1 was lower and IL-6 was higher providing possible explanation for the increase in %HMWM in ESKD. The %HMWM dropped significantly in the postdialysis sample. Mortality at 4 years was significantly associated with vWF : Ag. There are higher plasma vWF : Ag levels and a small increase in HMWMs in the ESKD milieu. The acute drop in the %HMWM of vWF postdialysis appears to be due to shear forces encountered during the dialysis procedure. The contribution of these abnormalities to either a pro-thrombotic and/or pro-bleeding phenotype in this population requires further study.