Proliferative inflammatory atrophy: a background lesion of prostate cancer?

Proliferative inflammatory atrophy (PIA) belongs to the atrophic lesions that frequently occur in the prostate. The location of PIA in the periphery of the gland near to prostate carcinoma or even showing direct transition to malignant or pre-malignant epithelia suggested a connection between PIA and prostate cancer. Further findings in PIA, such as imbalance between proliferation and apoptosis and detection of molecular-biological abnormalities specific for oxidative stress or malignancy, supported this hypothesis. Recently, epidemiological studies including large cohorts of patients have been undertaken in order to investigate the causal connection between PIA and prostate carcinoma. The current understanding of PIA allows us to consider it as a benign lesion with certain genetic instability which can degenerate into prostate intraepithelial neoplasia or carcinoma, provided that the balance between anti-carcinogens and carcinogens is perturbed. To evaluate the role of PIA as a precursor lesion of prostate cancer, further examinations of genetic or epigenetic aberrations are required.