Acinar carcinoma of the prostate is the third most frequently register
ed cancer and its incidence is expected to increase as life expectancy
increases. Consequently, there have been attempts to introduce possib
le screening programmes for early detection of prostatic carcinoma. In
this context the histopathologist has a role in that potential pre-ne
oplastic lesions have to be recognized. Two such pre-neoplastic lesion
s in the prostate are adenomatous hyperplasia and prostatic intraepith
elial neoplasia. In this article the histological features of these le
sions, their differential diagnosis and their pre-malignant potential
are reviewed.