Epitheliosis, infiltrating epitheliosis, and radial scar

The lesion termed “infiltrating epitheliosis” (IE) by Azzopardi is described using his original criteria. The differential diagnosis from radial scar (RS) is discussed. It appears that IE and RS are histologically and histogenetically different and are also associated with a different risk of carcinoma. IE can be associated with either in situ or invasive carcinoma, whereas RS being more like a process of involution is very seldom involved by a carcinoma. Therefore, whatever name is used among the several found in the literature, it should be made clear they are not interchangeable when reporting on lesions like IE and RS.