Study of factors affecting the incidence of skin cancer in patients after liver transplant

Abstract: Background: Many factors are currently being identified as potential inductors of skin cancer in patients after a liver transplant, among them, immunosuppressive regimen. Objective: To study the factors that influence the incidence of skin cancer in patients after liver transplant. Methods: We have carried out a retrospective and observational study with 170 transplanted patients who had undergone transplantation from 1997 to 2010. We have adjusted the multiple logistic regression model (saturated model) to the ensemble of collected data using skin cancer as dependent variable, indicated in anatomopathological analysis between 1997 and 2014. Results: Incidence of skin cancer was 9.4%. Predictors were incidence of diabetes in the third year after the transplantation (p=0.047), not using tacrolimus in the first year after the transplantation (p=0.025) and actinic keratosis (p=0.003). Study Limitations: An important limitation is that the interpretation of the results was based on information collected of patients undergoing transplantation at a single center. Future research, multicentric and involving larger and more diverse populations, are needed. Conclusions: Factors found might contribute to Brazilian surveillance programs associated with decreased incidence of skin cancer.

Determinação da atividade fotoprotetora e antioxidante em emulsões contendo extrato de Malpighia glabra L. - Acerola / Determination of photoprotective and antioxidant activities in emulsions containing extract of fruit of Malpighia glabra L (acerola)

The use of plant extracts in an attempt to protect the skin against photoaging has increased considerably, since many of these extracts have compounds with photoprotective activity or which act synergistically with sunscreens, and also have a high antioxidant potential. The aim of this study was to assess the in vitro antioxidant and photoprotective activities of dry acerola extract incorporated into O/W emulsions, with or without chemical sunscreen. Physicochemical and microbiological analyses were performed during stability evaluations. The emulsion containing extracts of acerola showed absorption in the UVB region, with maximum absorbance at 290nm. At the concentration used, the acerola did not exhibit SPF ≤2 and thus cannot be considered a fruit with photoprotective potential, but antioxidant activity was confirmed in the formulation. The combined emulsion of acerola extract and chemical filters performed well in the stability tests and showed synergistic action in protecting the skin from being damaged by UV irradiation.

O emprego de extratos vegetais na tentativa de proteger a pele contra o fotoenvelhecimento vem crescendo muito, uma vez que muitos destes extratos apresentam compostos com atividade fotoprotetora ou sinérgica em associação a filtros solares, além do alto potencial antioxidante. Esta pesquisa teve como objetivo avaliar a atividade antioxidante e fotoprotetora in vitro do extrato seco de acerola veiculada em emulsões do tipo O/A e emulsões acrescidas de filtros solares químicos. Ensaios físico-químicos e microbiológicos foram realizados durante a avaliação de sua estabilidade. A emulsão composta pelo extrato de acerola apresentou absorção na região UVB com absorbância máxima em 290 nm. Na concentração utilizada, a acerola não apresentou FPS ≤2, assim não pode ser considerado planta com potencial fotoprotetor, porém foi confirmada atividade antioxidante na formulação. A associação do extrato de acerola com os filtros químicos apresentou-se estável frente aos ensaios de estabilidade e ação sinérgica na proteção da pele contra os danos induzidos pela radiação UV.