Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio Alone or Combined with Prostate-Specific Antigen for the Diagnosis of Clinically Significant Prostate Cancer

Background: Many patients undergo unwanted prostate biopsy due to unreliability of prostate-specific antigen (PSA). PSA density (PSAD), free PSA, free-to-total PSA ratio, prebiopsy MRI are used to diagnose prostate cancer (PCa). Since 1863, correlations between inflammation and cancer have been identified and explored; thus, the role of various blood parameters in detecting cancer has been studied, especially neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). Here, we evaluated whether these parameters before prostate biopsy can diagnose prostate cancer in our hospital.Methods: We conducted a retrospective study from January 2014 to January 2018. Prostate cancer patients were divided into significant cancer (Gleason Score ≥ 7) and insignificant cancer (Gleason Score < 7). NLR, PLR, and other clinical parameters were taken before the prostate biopsy. We then analyzed the associations of NLR and PLR alone or with PSA, with significant prostate cancer. Results: We included 463 patients, of whom 60.3% (279) had prostate cancer and 75.6 % (211) had a Gleason score (GS) of ≥ 7. PSA and PSAD in the clinically significant prostate cancer patient group were around two times more than those in the insignificant prostate cancer group. PV, NLR, PLR, and combined markers were more in the GS ≥ 7 population group. PSA combined with PLR (PPLR) and PSA with NLR (PNLR) had better area under a curve (AUC) (0.732 and 0.730, resp.), with statistical significance, than PSA, NLR, and PLR alone (0.723, 0.585, and 0.590). In the multivariate analysis using separate models with PSA and NLR or PLR compared to age, DRE-positive lesions, PV, PSAD; PNLR, and PPLR were statistically significant in finding aggressive prostate cancer. When combined markers were used together, despite the high correlations, PSA and NLR were nearly significant (p = 0.062) in detecting the GS ≥ 7 population.Conclusion: The combined use of PSA with PLR and PSA with NLR helps detect the differences between clinically significant and insignificant prostate cancer.