Immunohistochemical expression of interleukin-2 receptor and interleukin-6 in patients with prostate cancer and benign prostatic hyperplasia: Association with asymptomatic inflammatory prostatitis NIH category IV

OBJECTIVE: This study prospectively investigated the immunohistochemical expression of interleukin-2 receptor (IL-2R) and interleukin-6 (IL-6) in patients with prostate cancer and benign prostatic hyperplasia (BPH), and a possible association of these conditions with asymptomatic inflammatory prostatitis National Institutes of Health (NIH) category IV. MATERIALS AND METHODS: The study included 139 consecutive patients who underwent transurethral resection of the prostate and transvesical enucleation of the prostate (n = 82) or radical prostatectomy (n = 57). To characterize inflammatory changes the criteria proposed by Irani et al. [J Urol 1997;157:1301-3] were used. IL-2R and IL-6 expression was studied by a standard immunohistochemical method. Results were correlated with tumour, node, metastasis stage, Gleason scores, total prostate-specific antigen, International Prostate Symptom Score and body mass index. RESULTS: IL-2R and IL-6 expression was significantly higher in neoplastic prostate cancer tissue than in normal tissue of prostate cancer patients (p < 0.001 and p < 0.04, respectively). Prostate cancer patients with prostatitis showed significantly higher IL-2R expression than those without inflammation (p < 0.03). In patients with BPH, expression of IL-2R as well as IL-6 was higher in patients with prostatitis than in those without (p < 0.01 and p < 0.02, respectively). CONCLUSIONS: IL-2R and IL-6 expression was significantly higher in prostate cancer tissue than in normal tissue. Patients with asymptomatic inflammatory prostatitis NIH category IV showed significantly greater activity.