Chronic inflammation of the prostate type IV with respect to risk of prostate cancer

Background: Chronic inflammatory infiltrate (CII) might be involved in prostate cancer (PCA) and benign hyperplasia (BPH); however, its significance is controversial. Chronic inflammatory prostatitis type IV is the most common non cancer diagnosis in men undergoing biopsy because of suspected PCA. Objective: To evaluate potential associations of coexistent CII and PCA in biopsy specimens after prostate assessment. Design, setting, and participants: Between January 2007 and December 2008, 415 consecutive patients who underwent prostate biopsy were retrospectively evaluated. The investigated variables included Age (years) and PSA (ug/l); moreover, CII+, glandular atrophy (GA+), glandular hyperplasia (GH+), prostate Intraepithelial neoplasm (PIN+), atypical small acinar cell proliferation (ASAP+) and PCA positive cores (P+) were evaluated as categorical and continuous (proportion of positive cores). Outcome measurements and statistical analysis: Associations of CII+ and PCA risk were assessed by statistical methods. Results and limitations: In the patient population, a biopsy core positive for PCA was detected in 34.2% of cases and the rate of high grade PCA (HGPCA: bGS ! 8) resulted 4.82%. CII+ significantly and inversely associated with a positive biopsy core P+ (P < 0.0001; OR = 0.26) and HGPCA (P = 0.0005; OR = 0.05). Moreover, the associations indicated that patients with coexistent CII+ on needle biopsy were 74% less likely to have coexistent PCA than men without CII+ as well as 95% less likely to have HGPCA in the biopsy core than men without coexistent CII+. There were limits in our study which was single centre and included only one dedicated pathologist. Conclusions: There was an inverse association of chronic inflammation of the prostate type IV and risk of PCA; moreover, HGPCA was less likely to be detected in cancers associated with coexistent CII. In prostate microenvironment, prostate chronic inflammation may be protective; however, its role in PCA carcinogenesis remains controversial and needs further research.