Based on the hypothesis that the S100/calgranulins are also involved in the pathogenesis of PCA, this study aimed to compare S100A8/A9 and S100A12 immunostaining between tissues of prostatic neoplasia, marked prostatitis, benign prostatic hyperplasia (BPH, in some cases accompanied by minimal to mild chronic non-suppurative prostatitis), and a healthy prostate. The gene discussed is S100A12; the disease is posterior cortical atrophy.