The significance of the Darier-like solar keratosis and acantholytic change in preneoplastic lesions of the epidermis

Fifty-two lesions of solar keratosis from 40 patients were studied prospectively for the presence of Darier-like changes and acantholysis. Twenty-seven per cent of specimens showed some degree of these changes. The affected lesions tended to be larger and were less common on the hands, but were otherwise clinically indistinguishable from other solar keratoses. Histologically, the specimens with Darier-like changes were significantly thicker and more dysplastic. The autoradiographic labelling index was not different for the lesions with these changes indicating similar cell kinetic characteristics. It is suggested that acantholytic separation of epidermal cells within a solar keratosis may signify that the lesion has a greater invasive potential than a solar keratosis not showing this change.