Significance of duct-acinar dysplasia in prostatic carcinogenesis.

In summary, duct-acinar dysplasia is defined as a one-dimensional continuum of acquisition of malignant morphologic features by the cells lining preexisting ducts and acini. At the far end of the continuum, invasive carcinoma can be demonstrated to arise directly from the walls of dysplastic ducts, leaving no room for doubt concerning the malignant potential of this lesion. The identification of dysplasia in nearly half of prostates without cancer and nearly all prostates with cancer suggests that most adenocarcinomas in the prostate may develop from dysplasia. Dysplasia is further defined as a biologic lesion in which cytoplasmic differentiation is reduced and disordered and the intracellular processing of cytoplasmic proteins and glyco-proteins is altered. Further study of these early biologic changes may yield important insights into the biologic nature of the process of malignant transformation.