Nonspecific granulomatous prostatitis in association with eosinophilic epithelial metaplasia and prostatic...

We present the first case of nonspecific granulomatous prostatitis (NSGP) associated with both eosinophilic epithelial metaplasia (EM) in benign glands and prostatic adenocarcinoma (PCa). The patient was a 68-year old man with a history of obstructive prostatic syndrome. After a transurethral resection of the prostate, the histologic analysis revealed NSGP and PCa. EM was seen in benign peri-granulomatous secretory epithelial cells as PAS Diastase positive granular eosinophilic transformation of the apical cell cytoplasm. This unusual cell appearance closely simulated the Paneth cell-like changes found in PCa. Negative chromogranin expression and weakly positive P504S immune staining in the foci of EM, surrounded by P63 positive basal cells confirmed the benign EM - phenotype. The combination of NSGP with both EM and PCa has not been reported in medical literature so far. Some observations concerning their differential diagnosis are suggested.