This article reviews diagnostic criteria for carcinoma, indications for rep
eat biopsy, and cancer mimics. Previously it was not possible to define ful
ly the minimal criteria for prostatic adenocarcinoma owing to a lack of und
erstanding of all of its mimics. These criteria for carcinoma are now suffi
ciently refined so that one can separate out a category of suspicious foci
that fall below the diagnostic threshold for malignancy.