Histopathologic and histochemical study of the solar elastosis in actinic cheilitis

Abstract

The actinic cheilitis (AC) is a diffuse lesion of the vermillion of the lower lip, due to excessive exposure of the lips to the ultraviolet radiation. It may show histomorphologic alterations indicative of the abnormal differentiation. Histopathologically, the main characteristic of the skin photoaged is the accumulation of the basophilic material, amorphous, rich in elastic fibers, referred to as solar elastosis. This aspect is demonstrated by the AC; however, the most of the researchers do not investigate lesions provoked by actinic damages like AC. The objective is to investigate the degree of dysplasic and the pattern of organization of collagens and elastics fibers of this lesion. Using H&E, Picrossirius and orcein of Weigert, respectively the lesions were studied.  The most of the patients were males situated in the fifth decade of life. Histopathologically, six cases showed discrete dysplasia, four moderate dysplasia and three intense dysplasia. In the extracellular matrix was observed absent collagen fibers in the areas corresponding to the solar elastosis.  In these areas, they were substituted by elastic fibers originating probably a substance similar to elastin. This material is present in actinic cheilitis. Like extracellular matrix exert action on mechanism of cellular migration and invasion, this study is important to understand the participation of these components because actinic cheilitis may exhibit malignant alteration.