Focal prostatic atrophy: morphologic classification and immunohistochemistry.

Abstract

Objective: To describe the morphology of focal prostatic atrophy and propose a comprehensive histologic classification for a proper diagnostic recognition.

Study design: A broad immunohistochemical study was performed as an adjunct to its recognition as well as a contribution to pathogenesis.

Results: A morphologic continuum was seen on needle biopsies. Chronic inflammation was present only in complete atrophy. Immunohistochemical findings in partial atrophy are similar to normal acini. Luminal compartment in complete atrophy shows aberrant expression of 34betaE12 favoring an intermediate phenotype. ERG negativity in all variants of atrophy may have value in the identification of the lesion.

Conclusion: The morphologic findings favor a continuum probably partially preceding complete atrophy. Chronic inflammation may be a secondary phenomenon seen only in complete atrophy. Overexpression in complete atrophy of glutathione S-transferase pi relates to oxidative stress possibly related to chronic ischemia, of c-Met favors the concept that intermediate cells may be target for carcinogenesis, and of CD44 may be related to the recruitment of inflammatory cells.