The Significance of Histological Chronic Prostatitis in Transrectal Prostate Biopsy

Research Article

Austin J Urol. 2014;1(2): 5.

The Significance of Histological Chronic Prostatitis in Transrectal Prostate Biopsy

Villeda-Sandoval CI, Herrera-Cáceres JO, Ruiz-Hernández JA, Castillo-de-León J, Castillejos-Molina RA and Rodriguez-Covarrubias F*

Department of Urology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico

*Corresponding author: Rodriguez-Covarrubias F, Department of Urology, Instituto Nacional de Ciencias Médicas y Nutrición “Salvador Zubirán”. Vasco de Quiroga 15, Col. Sección XVI, Tlalpan 14000, Mexico City, Mexico

Received: June 21, 2014; Accepted: July 28, 2014; Published: Aug 04, 2014

Abstract

Purpose: The histological finding of chronic prostatitis (CP) has been linked to higher levels of prostatic specific antigen (PSA), prostate cancer (PCa) and lower urinary tract symptoms. However, its clinical meaning is still uncertain. We performed a retrospective analysis to determine the role of CP and its relationship to the diagnosis of PCa.

Methods: Patients undergoing prostate biopsy from January 2008 to June 2013 were selected from our database. Those with the histological finding of CP were the focus of this analysis. They were categorized depending on the presence or absence of this feature. We determined the association between CP and PCa diagnosis using univariate and multivariate analyses. Statistical significance was stated as p<0.05.

Results: 540 patients were selected. The mean age was 65 ± 7.51 years and median PSA of 7.49 ng/ml. Two groups were defined: 1) 331 patients with chronic prostatitis and 2) 209 without chronic prostatitis. No statistical differences were found between groups regarding age, PSA, IPSS score, prophylactic antibiotic use, comorbidities, alpha-blocker or 5-α-reductase inhibitor therapy, transurethral catheter at biopsy or infectious complications. Significant differences were found for previous hospitalizations, number of previous biopsies, suspicious digital prostate exam, number of cores taken, prostate volume, cancer diagnosis, percentage of positive cores and Gleason score >=7. A multivariate analysis model showed “protective” effect between CP and diagnosis of PCa (HR 0.17, p= <0.01).

Conclusion: Our results suggest that the histological finding of CP is inversely related to PCa diagnosis.

Keywords: Chronic Prostatitis; Prostate Biopsy; Prostate Cancer; Mexico

Abbreviations

ASAP: Atypical Small Acinar Proliferation; CP: Chronic Prostatitis; LUTS: Lower Urinary Tract Symptoms; NIH: National Institutes of Health; PSA: Prostate Specific Antigen; PCa: Prostate Cancer; BPH: Benign Prostatic Hyperplasia; TRPB: Trans-Rectal Prostate Biopsy; DRE: Digital Rectal Exam; MetS: Metabolic Syndrome

Introduction

From a clinical point of view, chronic prostatitis (CP) refers to a condition characterized by pelvic pain and lower urinary tract symptoms (LUTS). When confirmed histologically it is characterized by inflammatory infiltrates within prostate tissue [1]. According to the National Institutes of Health (NIH), prostatitis can be classified as type I: acute-bacterial prostatitis, type II: chronic-bacterial prostatitis, type III: chronic prostatitis/chronic pelvic pain syndrome and type IV: asymptomatic [2]. The latter presents only, as histological diagnosis without symptoms. CP has been linked to nonspecific elevation of prostate specific antigen (PSA) [3], development of prostate cancer (PCa) [4] and progression of benign prostatic hyperplasia (BPH) [5]. A transrectal prostate biopsy (TRPB) is the most common method to obtain prostatic tissue [6]. Although pelvic pain and prostatic enlargement are not indications for this procedure, it has been found that less than 5% of biopsies show significant evidence of inflammation (10 or more leukocytes per high-power field) [7]. However, the diagnosis of CP is found more often than expected in TRPB performed to rule out PCa.

The aim of our study was to assess the association of histologically confirmed CP detected in TRPB advocated to PCa diagnosis and to determine the potential role of this finding.

Material and Methods

A retrospective analysis of our institutional database of TRPB performed from January 2008 to June 2013 was performed. The procedure technique and antibiotic prophylaxis used at our Institution have been previously reported [8,9]. Only patients with complete medical records were included. Information was obtained from clinical charts including perioperative variables, histopathological reports, and follow-up data. Patients were categorized according to the presence or absence of CP on histological reports. CP was defined as “CP type IV” according to the NIH classification of prostatitis syndromes (asymptomatic inflammatory prostatitis). A comparison between groups was made to identify clinical and pathological differences. Student’s t-test for independent groups was used for continuous variables and Chi square and Mann-Whitney U tests were used for nonparametric variables. A multivariable model was created to analyze the impact of CP on the detection of PCa. A p<0.05 was determined as significant. Statistical analysis was made with the aid of SPSS® v. 17.0 (IBM®, New York) program.

Results

A total of 540 patients were included with a mean age of 65 ± 7.51 years. Median PSA was 7. 49 ng/ml. Indications for TRPB were high PSA in 63%, suspicious digital rectal exam (DRE) in 36.2%, atypical small acinar proliferation (ASAP) in 1 patient and active surveillance in another patient. Two groups were integrated: 1) 331 patients with chronic prostatitis (61.3%) and 2) 209 patients without chronic prostatitis (38.7%). Of these, 172 (31.8%) had PCa and 368 (68.2%) did not. Of the 331 patients with CP, 51 (15.4%) had simultaneous PCa. On the other hand, of the 209 without CP, 121 (57.9%) had a PCa report in pathology.

Clinical characteristics are described in Table 1. There were no differences except for previous hospital admissions (p=0.01) and number of previous biopsies (p=0.03) Features concerning indications for TRPB and histological information are summarized in Table 2 & 3, respectively. We found differences regarding suspicious DRE (p<0.01), number of biopsy cores (p<0.01), prostatic volume (p=0.04), positive core percentage (p<0.01) and Gleason score ≥7 (p<0.01). PCa was diagnosed in 57.9% and 15.4% of patients without and with CP, respectively (Table 3; p<0.01).