Diagnostic and prognostic significance of prostate specific antigen and serum interleukin 18 and 10 in patients with locally advanced prostate cancer: a prospective study

Abstract

Background: Prostate cancer is one of the most common cancers afflicting men today. Prostate biopsy, an invasive procedure is generally used for diagnoses but attempts are being made to find accurate and precise non-invasive biomarkers. Diagnostic accuracy of prostate specific antigen (PSA) has been well documented. Serum interleukin-18 (IL-18) and interleukin-10 (IL-10) have shown their diagnostic ability in other cancers but not investigated well in prostate cancer. This study, thus determines the diagnostic and prognostic significance of PSA, IL-18 and IL-10 prospectively in patients with carcinoma prostate.

Methods: A total of 149 patients, aged 40-84 yrs were investigated during April 2007 to July 2010 and recruited for this study after Institutional ethical approval. Of the total of 149 patients, 71 had biopsy proven prostate cancers (TNM stage: T2=17, T3=26 and T4=28) and 78 clinical benign prostate hyperplasia (BPH). Peripheral blood samples of all patients and 71 age matched control subjects were obtained at baseline and estimation of PSA, IL-18 and IL-10 was done by enzyme linked immunosorbent assay (ELISA). Carcinoma prostate patients were followed for three years. Data were analyzed with ANOVA, ROC curve analysis and survival analysis.

Results: The baseline levels of PSA, IL-18 and IL-10 in all groups of carcinoma prostate were found to be significantly (p<0.01) higher than both Control and BPH. The levels of IL-18 and IL-10 also found to be elevated significantly in stage T3 (p<0.05) and T4 (p<0.01) as compared to stage T2. The levels especially of IL-18 is found to be well associated with progression of the disease of various groups (r=0.84, p<0.01). In contrast, IL-10 showed significant direct association with progression of carcinoma (r=0.84, p<0.01) while inverse relation with survival duration (r=-0.48, p<0.01) and survival rate (χ2=8.98, p=0.0027; Hazard ratio=0.37, 95% CI=0.18-0.69).

Conclusions: Study concluded that serum IL-18 has potential to be a better diagnostic marker with higher specificity and sensitivity and IL-10 may be valuable as a prognostic marker than PSA in carcinoma prostate.