Archivio Italiano di Urologia e Andrologia 2018; 90, 4 270 ORIGINAL PAPER Lymphocyte-to-monocyte ratio is a valuable marker to predict prostate cancer in patients with prostate specific antigen between 4 and 10 ng/dl Volkan Caglayan, Efe Onen, Sinan Avci, Murat Sambel, Metin Kilic, Sedat Oner, Mustafa Murat Aydos, Halil Emre Yıldız University of Health Sciences, Bursa Yuksek Ihtisas Training and Research Hospital, Bursa, Turkey. Objective:To evaluate the diagnostic value of serum inflammation markers derived from complete blood count in diagnosis of prostate cancer (PCa). Methods: We retrospectively analyzed the data of 621 patients who underwent prostate biopsy between March 2013 and April 2018. Age, prostate specific antigen (PSA), free PSA, platelet count, neutrophil count, lymphocyte count, monocyte count, prostate volume (PV) and pathology result of the patients were recorded. Patients were grouped as benign prostatic hyperpla- sia (BPH), prostatitis and PCa. Patients were also grouped according to PSA values, as PSA < 4 , PSA 4-10 and PSA > 10 ng/dl. Results: The mean lymphocyte-to-monocyte ratio (LMR) value of the patients with PCa was significantly lower in the entire cohort (p = 0.047). In the PSA 4-10 ng/dl range, LMR value wassignificantly lower in patients with PCa than those with BPH or prostatitis ( p = 0.012). In this PSA range, free/total PSA ratio and LMR were significant factors to predict PCa. The cut-off values of LMR, free/total PSA were 3.05 and 0.15 respectively. The sensitivities, spesificities, positive predictive values (PPV) and negative predictive values using LMR cut-off, free/total PSA cut-off and their combination were assessed. Specificity and PPV of the combination group were higher (97.2%, 83.3% respectively) compared to free/total PSA cut-off group (91.6%, 76.6%) and LMR cut-off group (67.8%, 43.7%). Conclusions: LMR is a useful tool at detecting PCa especially in patients with PSA value between 4 and 10 ng/dl. The combi- nation of free/total PSA ratio and LMR improves the diagnostic accuracy more than the use of free/total PSA ratio alone. KEY WORDS: Lymphocyte-to-monocyte ratio; Prostate cancer. Aubmitted 19 August 2018; Accepted 19 August 2018 Summary No conflict of interest declared. PCa and reduced the associated mortality. However, the low specificity of PSA can lead to unnecessary biopsies, overdiagnosis and overtreatment (3). PSA is organ but not cancer-specific, therefore it may be elevated in benign conditions such as benign prostate hyperplasia (BPH), prostatitis, urinary tract infections and trauma. After detection of elevated PSA, it is recom- mended to perform prostate biopsy (PBx) which is still the gold standard method for diagnosis of PCa. However PBx is associated with several complications, including pain, hematospermia, haematuria, hema- tochezia, and potentially severe infectious complications, ranging from urinary tract infections (UTIs) and prostati- tis to sepsis (4). Although PSA is a useful tool at detect- ing PCa, concern about performing unnecessary PBx considering overdiagnosis and complications is the cru- cial problem for urologists. Some PSA-related testing parameters (e.g., PSA density, free/total PSA ratio, PSA doubling time, and prostate health index test) have been used to improve the accuracy of PCa prediction (5). Thus, new biomarkers may be needed to improve deci- sion-making regarding initial management, including whether to biopsy. Over the last decade, it has become clear that systemic inflammation plays an important role in the develop- ment and progression of cancer. The markers of the sys- temic inflammatory response are usually based around composite ratios or cumulative scores of different circu- lating white blood cells representing the systemic responses of lymphoid/myeloid tissue. The main approach is to take the ratio of different white blood cells and then apply a prognostic threshold to the ratio such that outcome is effectively stratified. The most repeatedly validated examples of this approach are the neutrophil-lymphocyte ratio (NLR) based on the ratio of circulating neutrophil and lymphocyte counts, the platelet-lymphocyte ratio (PLR) based on the ratio of cir- culating platelet and lymphocyte counts and the lympho- cyte-monocyte ratio (LMR) based on the ratio of circulat- ing lymphocyte and monocyte counts. In this study, we aimed to investigate the role of the sys- temic inflammatory response markers prior to PBx at predicting histologic≠al outcomes. DOI: 10.4081/aiua.2018.4.270 INTRODUCTION Prostate cancer (PCa) is the second most frequently diag- nosed cancer and the fifth most common cause of can- cer-associated death in men worldwide (1). Despite the recent advances in diagnostic and therapeutic approach- es, it is still a major health concern especially in devel- oped countries and especially in elderly men (2). Serum prostate-specific antigen (PSA) is widely used as a biomarker for this cancer, and its widespread introduc- tion has undoubtedly enhanced the early detection of