Background: The roles of chronic inflammation and genomic instability have recently emerged as risk factors in prostate carcinogenesis. In this research, single cell gel electrophoresis (comet assay) parameters such as DNA damage, serum interleukin-17 (IL-17), and immature granulocyte (IG) levels were studied to identify the difference between prostate cancer patients and healthy control groups. Method: DNA damage was determined by alkaline comet assay in peripheral blood lymphocytes of prostate cancer patients and controls. The following variables were assessed as DNA damage parameters: Tail DNA (%), Tail Length, Tail Moment, Olive Tail Moment, and Head DNA (%). Outliers were defined and removed by 1.5× IQR rule. The concentration of IL-17 was determined by ELISA method in patients (n=40) and controls (n=40), ROC analysis was performed to determine the usefulness of the variable. IG counts were determined from the complete blood count analysis. Since comet assay variables had non-normal distribution (Shapiro-Wilk p <0.05), Mann-Whitney U test was used to compare the two groups. Results: In analyses where outliers had been excluded, Tail Length and Tail Moment were found to be significantly increased in patients compared to control subjects (p<0.001 & p=0.008, respectively), as expected due to greater DNA movement. The amount of Tail DNA (%) was found to be significantly decreased in patients (median 1.97%, IQR 0.21-3.59) compared to control subjects (median 3.97%, IQR 2.63-5.35; p<0.001), whereas Head DNA (%) was significantly increased correspondingly. Olive Tail Moment did not show a significant difference (p=0.377). Serum IL-17 concentration was significantly higher in control subjects (411.38 ng/mL) than in patients (204.58 ng/mL, p<0.0001), showing AUC of 0.8532 (95%CI: 0.7585-0.9480), 84% sensitivity and 80% specificity with a cut-off value of 237.6 ng/mL. IG levels were significantly increased in patients (mean 0.4431) compared to control subjects (mean 0.19). Conclusion: Parameters assessed using comet assay and serum IL-17 can be used to distinguish prostate cancer patients from controls. However, in some cases, these differences do not occur in the direction usually expected, indicating the complexity of the relationship between genomic instability, systemic inflammation, and prostate cancer.