167Archivio Italiano di Urologia e Andrologia 2019; 91, 3 ORIGINAL PAPER Role of sterile pyuria in association to elevated PSA values in the diagnosis of non-palpable prostate cancer? Selamettin Demir Department of Urology, The Ministry of Health, University of Health Sciences, Van Education and Research Hospital, Van, Turkey. Objectives: Although cancer is believed to develop and progress with the involvement of inflammation, it is still unclear what the correlation between inflammation and prostate cancer is. This study based on results of transrectal ultrasound-guided prostate biopsies aimed to determine whether C-reactive protein (CRP) and sterile pyuria were clinically useful in the evaluation of patients with suspect of prostate cancer. Materials and methods: This study is a cross-sectional prospec- tive study of patients without clinical prostatitis symptoms. Characteristics of the 200 consecutive patients recruited were 3-20 ng/mL value of serum prostate-specific antigen (PSA), normal digital rectal examination finding, and sterile urine culture result. All patients underwent 12-core prostatic biopsy. 163 of the 200 patients had benign prostatic hyperplasia con- firmed through histology, while the residual 37 patients had prostate cancer. Patients with pre-treatment urinary leukocyte count ≤ 3/high power field were categorized as non-pyuria, whilst those with pre-treatment urinary leukocyte count > 3/high power field were categorized as pyuria. The serum CRP level was also used to differentiate patients before the biopsy. Subgroups were compared regarding a number of clinical vari- ables. Results: Histology revealed that 70% of pyuria patients and 38.5% of non-pyuria patients presented inflammation (p = 0.001). The pyuria group exhibited significantly higher total PSA compared to the non-pyuria group (p = 0.044). The two groups did not differ significantly regarding cancer detection rate (p = 0.752). CRP groups were similar regarding cancer detection and histologically-detected inflammation rates. Conclusion: In patients with no evidence of clinical prostatitis, sterile pyuria should be considered as a cause of increased PSA. Although sterile pyuria cannot predict non-palpable prostate cancer, it should be taken into account in urological evaluation in order to demonstrate minute prostatic inflammation due to its simplicity, convenience and non-invasiveness. KEY WORDS: Prostate cancer; Inflammation; Biopsy; C-reactive protein; Pyuria. Submitted 16 February 2019; Accepted 2 April 2019 Summary No conflict of interest declared. ularly non-palpable PCa has been increasingly identified at an early stage thanks to the common practice of screening for serum prostate-specific antigen (PSA). However, some have argued that biopsies should not be performed unnecessarily (4, 5), because, besides PCa, non-malignant prostate conditions, such as inflamma- tion, may be associated with high serum PSA as well (6, 7). The general assumption is that PCa develops and progresses due to inflammatory processes that disrupt the function of oncogenes and tumor inhibitors, thus damaging DNA and activating processes that can trigger tumor cells to grow and proliferate (8, 9). Therefore, PCa risk is considered to be elevated in men with intrapro- static conditions like proliferative inflammatory atrophy, prostatic intraepithelial neoplasia, and prostatitis, which may be induced by acute or chronic inflammation and are believed to be PCa precursors (9, 10). Abnormal digital rectal examination (DRE) results and/or PSA higher than 4.0 ng/mL are among the main markers warranting a prostate biopsy. If DRE suggests that PCa is likely, then biopsy is vital. On the other hand, PSA is the sole basis for deciding performance on non-palpable case biopsy, although it frequently yields false positives because its levels are increased by inflammation (11). Thus, it is important to prevent performing unnecessary biopsy for non-palpable case, and for this purpose, a number of PSA derived parameters have been consid- ered, including free-to-total PSA ratio, PSA density (PSAD) and PSA velocity (12, 13). This study sought to determine the extent to which the impact of inflammation on detection of cancer in speci- mens of prostate biopsy could be gauged based on serum C-reactive protein (CRP) level and urinary leukocyte count. MATERIALS AND METHODS Ethics committee approval was received for this study from the hospita ethics committee (number: 218/13). Written informed consent was obtained from patients who participated in this study. A number of 200 consec- utive patients were recruited for this study. All of them had serum PSA levels in the range 3-20 ng/mL, normal DRE findings and sterile urine culture results and under- went transrectal ultrasound-guided 12-core prostatic biopsy (TRUS-bx) beetwen Januray 2018 and February 2019. The study did not include patients with clinical signs of DOI: 10.4081/aiua.2019.3.167 INTRODUCTION In the US, prostate cancer (PCa) continues to be the can- cer with the second highest mortality rate in men, despite the fact that the number of men dying because of it is not as high as the number of those dying with it for other causes (1, 2). PCa risk is believed to be heightened by genetic and environmental factors, but the exact eti- ology remains unclear (3). Nevertheless, PCa and partic- Demir_Stesura Seveso 30/09/19 18:21 Pagina 167 Archivio Italiano di Urologia e Andrologia 2019; 91, 3 S. Demir 168 prostatitis, macroscopic pyuria, bacteria isolated in urine culture or systemic inflammatory conditions with poten- tial impact on serum CRP. The medication regimen con- sisted of 500 mg ciprofloxacin administered orally twice daily over a period of one week, with the first dose being given 24 hours before the procedure. Patients with pre- treatment urinary leukocyte count ≤ 3/high power field (h.p.f.) were categorized as non-pyuria, whilst those with pre-treatment urinary leukocyte count > 3/h.p.f. were categorized as pyuria. Furthermore, a positive group with serum CRP of 0.30 mg/dL or higher and a negative group with serum CRP of less than 0.30 mg/dL were dis- tinguished as well (25). Elecsys PSA kit (Roche Cobas 411, Tokyo, Japan) was used for measurement of free and total PSA values. Alongside the blood sample, urine culture and urine samples were also acquired prior to DRE. Latex CRP immunoturbidimetric kit (CRP-Latex ‘CRPLX’, Roche, Germany, and Model no. 6000; Hitachi, Tokyo, Japan) permitted measurement of serum CRP before treatment, with 0.30 mg/dL cut-off value with 93% specificity (25). Furthermore, a centrifugal automatic analyzer and a light microscope (Roche Miditron® Junior II, Germany) was used for urine analysis, while a scanner with a 6.5 MHz transrectal probe enabled performance of prostate transrectal ultrasonography (TRUS). Prostate scanning was performed in both transverse and sagittal planes whilst the patient was lying on his left side. The formula for a prostate ellipsoid (width × length × height × 0.523) helped to calculate the prostate volume and the total PSA was divided by the prostate volume to obtain the PSAD. Moreover, an automatic biopsy gun and an 18-gauge needle were employed to conduct the 12-quadrant biopsy under TRUS guidance. Prostate chronic inflammation was considered to be present when inflammatory cells, lymphocytes, plasma cells and/or histi- ocytes infiltrated prostatic biopsy spec- imens (14). Data were expressed as means ± SD. SPSS (IBM SPSS for Windows, ver.24) was used for comparison of the vari- ables associated with the different groups via Student’s t-test and Chi- Square test. Statistical significance was indicated by P value of less than 0.05. RESULTS The characteristics of every recruited patient are shown in Table 1. A pro- portion of 81.5% of patients (n = 163) was histologically confirmed to have benign prostatic hyperplasia (BPH), while the other 18.5% of patients (n = 37) had PCa. Histology also showed inflammation in biopsy specimens of a proportion of 49.5% of patients (n = 99). A comparison of PCa and BPH patients in terms of clinical variables is provided in Table 1. PCa patients had a mean age of 65.47 ± 7.84 years, while BPH patients had a mean age of 63.12 ± 7.73 years (p = 0.197). PCa patients had sig- nificantly higher total PSA compared to BPH patients (p = 0.001), but the two groups were similar in terms of free-to-total PSA ratios. Furthermore, PCa patients had significantly lower mean prostate volumes (p = 0.040), the PSAD values were significantly higher in the PCa than in the BPH group (p = 0.001). However, histology did not show a significant difference between the groups regarding inflammation (p = 0.738). A proportion of 35% of patients (n = 70) exhibited pyuria, while the other 65% (n = 130) did not, as revealed by the distribution of the urinary leukocyte count. A comparison of these two groups in terms of clinical variables, cancer detection rates, and histologically-detected inflammation is provided in Table 2. The groups were similar regarding age, free-to-total PSA ratio, prostate volume, and PSAD value, although the pyuria group exhibited significantly higher total PSA compared to the non-pyuria group (p = 0.044), as well as significantly higher serum CRP (p = 0.001). Furthermore, the groups were similar in terms of histological cancer detection rate (p = 0.752), but the pyuria group displayed greater histological inflammation (70% vs 38.5%; p = 0.001). Table 1. Characteristics of recruited patients. BPH ( n = 163) PCa (n = 37) P Age (years) 63.12 ± 7.73 (40-79) 65.47 ± 7.84 (45-80) 0.637 Urinary leukocyte count (n°/h.p.f.) 9.44 ± 19.18 (1-80) 10.71 ± 21.25 (1-90) 0.288 CRP (mg/dL) 1.23 ± 1.55 (0.10-8.00) 0.85 ± 0.63( 0.10-3.12) 0.520 T-PSA (ng/mL) 5.84 ± 2.54 (3.11-14) 8.72 ± 4.48 (3.65-20.00) 0.001* Prostate volume (mL) 57.77 ± 34.65 (17-260) 41.2 ± 20.36 (20-120) 0.040* Free to total PSA ratio (%) 19 ± 7 (5-38) 22 ± 23 (3-58) 0.752 PSAD 0.12 ± 0.07 (0.03-0.34) 0.25 ± 0.21 (0.07-0.85) 0.001* Histologically-detected inflammation rate 49.7% (81/163) 48.6% (18/37) 0.738 †Mean ± SD range; ‡BPH versus PCa. BPH: benign prostatic hyperplasia; CRP: C-reactive protein; PCa: prostate cancer; T-PSA: total prostate-specific antigen; PSAD: PSA density. Table 2. Clinical variables, cancer detection rates and histologically-detected inflammation rates in pyuria and non-pyuria groups. Non-pyuria group (n: 130) Pyuria group (n: 70) p Age (years) 60.45 ± 7.51 (40-80) 64 ± 6.07 (50-78) 0.637 CRP (mg/dL) 0.75 ± 0.78 (0.10-3.22) 2.39 ± 2.09 (0.28-8.00) 0.001* T.PSA (ng/mL) 6.42 ± 2.41 (3.29-15.07) 7.85 ± 3.88 (3.11-20.00) 0.044* Prostate volume(mL) 50.3 ± 34.4 (17-260) 55.4 ± 26.5 (30-130) 0.208 Free to total PSA ratio (%) 17 ± 9 (3-35) 20 ± 11 (11-58) 0.814 PSAD 0.14 ± 0.07 (0.04-0.61) 0.15 ± 0.12 (0.03-0.85) 0.288 Histologically-detected inflammation rate 38.5% (50/130) 70% (49/70) 0.001* Cancer detection rate 17.6% (23/130) 20% (14/70) 0.752 Mean ± SD range; ‡non-pyuria, urinary leukocyte count ≤ 3/h.p.f.; pyuria, urinary leukocyte count > 3/h.p.f.; CRP: C-reactive protein; h.p.f.: high power field; T-PSA: total prostate specific antigen; PSAD: PSA density. Demir_Stesura Seveso 30/09/19 18:21 Pagina 168 Two groups of positive CRP (71.5%, n = 143) and nega- tive CRP (28.5%, n = 57) were also distinguished based on the manner in which pre-treatment serum CRP levels were distributed. A comparison of these two groups in terms of clinical parameters, cancer detection rates, and histologically-detected inflammation is provided in Table 3. It was observed that the groups were similar regarding age, free-to-total PSA ratio, prostate volume, cancer detection rates, and histologically-detected inflammation and PSAD values. DISCUSSION Since the first isolation of serine protease PSA from prostate epithelial cells that was accomplished by Wang et al. in 1979, PCa began to be diagnosed and treated based primarily on PSA measurement (15). There are sig- nificant challenges involved in differentiating PCa from BPH, especially in cases with intermediate levels of PSA. Furthermore, PSA is not associated exclusively with PCa but is expressed by malignant as well as normal prostate glands. Efforts to make prostate biopsy more efficient directed attention to a number of factors associated with PSA, including the free-to-total PSA ratio, PSAD and PSA velocity (12, 13). Particular focus was put on serum markers like p53 antibody and insulin-like growth factor 1 (IGF-1) with the purpose of enhancing positive pre- dictive value (16, 17), which has also benefitted from PCa visualisation innovations, including magnetic reso- nance spectroscopic imaging, dynamic contrast- enhanced magnetic resonance imaging, positron emis- sion tomography and transrectal power Doppler imaging (18, 19). Reduction of negative biopsy rate as much as possible should be a key priority of management since prostate biopsy can entail a great deal of pain and could result in considerable morbidity. Besides PCa, benign conditions like benign prostatic hyperplasia, prostatic manipulation, and even asympto- matic and chronic prostatitis are associated with elevated levels of serum PSA (6, 7). It is well-known that the development and progression of numerous cancers are associated with the risk factor of inflammation (20), with pre-malignant modifications and adenocarcinoma of the prostate having been found to be underpinned by inflammatory processes (21). Cytokines stimulating inflammation, especially interleukin 6 (IL-6) (22), have a significant influence on systemic inflammation markers like CRP (23). However, IL-6 is not only involved in the mobilization of inflam- matory cells but is also believed to be mitogenic in the case of prostate cells (24). In a retrospective study on 284 patients showing no cancer signs in sextant ultrasound-guided biopsies, Morote et al. reported that 23.2% of patients had non-malignant tissue without inflammation, 68.3% dis- played chronic prostatitis, and 8.4% displayed acute prostatitis, which implied that BPH specimens had a high rate of prostatic inflammation (11). In a different retrospective study, Tomonori et al. found that 53.5% of BPH patients and 14.1% of PCa patients had inflammation (25). In the present study, histology revealed that 49.7% of BPH patients and 48.6% of PCa patients had inflamma- tion. Asymptomatic prostatitis are diagnosed when inflammatory cells are present in histological prostate biopsy specimens according to the National Institute of Health (NIH) (14). It was noted that serum PSA was sig- nificantly higher in pyuria patients with a urinary leuko- cyte count exceeding 3/h.p.f. (p = 0.044), but the two groups were similar regarding the cancer detection rate (p = 0.752). Histology revealed that pyuria patients had a high inflammation rate, even though clinical symptoms of prostatitis were absent (p = 0.001) (Table 2). Furthermore, NIH-IV prostatitis is often accompanied by prostate hyperplasia (11, 25-27). However, the results obtained in this study did not determine that serum CRP was clinically useful in PCa screening. Pyuria patients had higher levels of serum CRP compared with non- pyuria patients (Table 3). High levels of both PSA and CRP may be due to inflam- mation. Meanwhile, CRP positive and negative groups did not differ in terms of inflammation rate and cancer detection rate. It was deduced that prostatic inflamma- tion was more reliably signaled by urinary leukocyte count than serum CRP and that serum CRP and elevated PSA were not closely correlated. According to Tomonori et al., non-palpable PCa and BPH might be differentiated based on an inflammatory index like urinary leukocyte count applied in a clinical setting (25). However, the present study did not support this claim, despite observing that minute prostatic inflamma- tion could be reliably identified based on the urinary leukocyte count. Meanwhile, in a different study con- ducted on 61 patients displaying PSA in the range 4-10 ng/mL, normal DRE outcomes and inflammation in expressed prostate secretion, Karazanashvili et al aimed to come up with solutions for making PCa screening more accurate (28). To that end, they used PSA value modification following treatment with antibiotics as a diagnostic approach. PCa was detected in only 6% of patients with reduced PSA values, whereas all patients exhibited prostate inflammation. On the other hand, PCa was detected in 83% of patients with unaltered or ele- 169Archivio Italiano di Urologia e Andrologia 2019; 91, 3 Urinary inflammation and prostate cancer Table 3. Clinical variables, cancer detection rates and histologically-detected inflammation rates in positive- and negative- C-reactive protein groups. CRP negative (n: 57) CRP positive (n: 143) P Age (years) 63.15 ± 7.20 (40-77) 60± 6.37 (43-80) 0.245 T-PSA (ng/mL) 6.80 ± 2.45 (3.23-14.58) 7.15 ± 3.63 (3.11-20.00) 0.991 Prostate volume(mL) 55.10 ± 37.32 (17-120) 59.88 ± 29.53 (20-260) 0.200 Free to total PSA ratio (%) 19 ± 7 (3-55) 16 ± 8 (4-58) 0.738 PSAD 0.15 ± 0.06 (0.03-0.35) 0.17 ± 0.12 (0.04-0.85) 0.490 Histologically-detected inflammation rate 49.1% (28/57) 49.6% (71/143) 0.857 Cancer detection rate 12.3% (7/57) 20.1% (30/143) 0.248 Mean ± SD range; ‡Negative, serum CRP < 0.30 mg/dL; positive, serum CRP ≥ 0.30 mg/dL; CRP, C-reactive protein; T-PSA, total prostate specific antigen; PSAD, PSA density. Demir_Stesura Seveso 30/09/19 18:21 Pagina 169 Archivio Italiano di Urologia e Andrologia 2019; 91, 3 S. Demir 170 vated PSA values and prostate inflammation was observed in 17% of these patients. The authors conclud- ed that PCa screening could be made more accurate by evaluating PSA value modification following treatment with antibiotics since high PSA was determined to a sig- nificant extent by chronic prostatitis. CONCLUSIONS Male individuals are at high risk of asymptomatic pro- statitis if their levels of PSA are high and they present normal DRE outcomes. Prior to biopsy, antibiotics or antiphlogistics should be given to pyuria patients and it is advisable to measure PSA repeatedly as well. In patients without evidence of clinical prostatitis, sterile pyuria should be kept in mind as a cause of increased PSA. Although urine leukocyte count cannot predict non-palpable prostate cancer, it should be incorporated in routine urological evaluation to demonstrate minute prostatic inflammation due to its simplicity, convenience and non-invasiveness. 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Prostate-specific antigen (PSA) value change after antibacterial therapy of prostate inflam- mation, as a diagnostic method for prostate cancer screening in cases of PSA value within 4-10 ng/mL and nonsuspicious results of digital rectal examination. Eur Urol. 2001; 39:538-43. Correspondence Selamettin Demir, MD (Corresponding Author) drselami1978@hotmail.com The Ministry Of Health, University of Health Sciences, Van Education and Research Hospital, Van (Turkey) Demir_Stesura Seveso 30/09/19 18:21 Pagina 170