Comparison between clinical significance of serum proinflammatory protein interleukin-6 and classic tumor markers total PSA, free PSA and free/total PSA prior to prostate biopsy.

The aim of the study was to clarify whether serum levels of proinflammatory cytokine interleukin-6 (IL-6) could be a useful marker in prostate diseases. Serum IL-6 was determined prior to prostate biopsy procedure in 82 patients with prostate adenocarcinoma (PCa), 25 patients with benign prostatic hyperplasia (BPH), 24 patients with high-grade prostatic intraepithelial neoplasia (PIN) and 17 patients with chronic prostatitis. Serum IL-6 levels were compared with total PSA (tPSA), free PSA (fPSA) and the free/total ratio (f/tPSA) serum levels. Statistically significant difference was not found in serum IL-6 levels among the four groups (p = 0.088). However, the patients with poorly differentiated PCa with Gleason score (GS) 4 + 3 = 7 and > 7 had significantly higher serum IL-6 levels than the patients with moderately differentiated PCa with GS 3 + 4 = 7 and < 7 (p = 0.007). The findings suggest that serum IL-6 level might be a potentially useful marker for poorly differentiated PCa.