BOUNDARY IN THE PATHOLOGICAL EVALUATION OF PREMALIGNANT PROSTATIC LESIONS

The term ''premalignant lesion'' encompasses diverse morphological ent ities that vary in their phenotype and biologic behavior. This diversi ty makes the group heterogeneous, although these lesions share the com mon factor of having pathologic characteristics intermediate between n ormal (benign) and neoplastic (malignant). This creates dilemmas in re aching a pathologic diagnosis and in predicting biological behavior. T he aim of this article is to present a series of case studies which hi ghlight difficult diagnostic situations. Emphasis is placed on diagnos tic criteria and available procedures. At present, two distinct atypic al prostatic lesions are recognized: one in which the change is mainly cytological (PIN), and another in which the change is mainly architec tural (Atypical adenomatous Hyperplasia or AAH).