Study population and selection criteria
All adult male patients seen in our urology division between February 2017 and July 2018 with indications for prostate biopsy (suspicious findings on digital rectal examination, serum prostate specific antigen greater than 4.0 ng/ml or prostate specific antigen density greater than 0.15 ng/ml/g) who could void spontaneously as evidenced by peak urine flow measurements were considered for inclusion into this quasi-experimental study. Patients with acute urinary retention on indwelling suprapubic or urethral catheter, those having ongoing haematuria associated with clot passage, those with bleeding disorders, those on alpha-adrenergic receptor blockers or 5-alpha reductase inhibitors, and those with history of prior prostate surgery were excluded. Other exclusion criteria included the presence of Parkinson's disease, previous cerebrovascular accident or other neurological disease which could affect voiding function, and diabetes mellitus.
This study was approved by the Institutional Health Research Ethics Committee and informed consent was obtained from all patients recruited for the study.
Study protocol
Following patient enrollment, those on anticoagulants and acetyl salicylic acid were instructed to stop taking it at least 3–5 days and 7–10 days before the procedure, respectively, while those with ongoing urinary tract infection, as diagnosed by a positive urine culture, were treated with antibiotics according to the antimicrobial sensitivity pattern of the cultured organism. All patients on antibiotics for the treatment of infection were allowed to complete such treatment, and clearance of infection was determined clinically and confirmed by negative urine culture before their biopsies were taken.
Data on the patient’s demographic, clinical and laboratory details were obtained and entered into the proforma. Baseline International Prostate Symptoms Score (IPSS) and bother scores were determined just before the procedure using IPSS questionnaire. This instrument has a set of 7 questions assessing three storage symptoms of frequency, urgency and nocturia, and four voiding symptoms of incomplete emptying, intermittency, weak stream and straining. These are scored from zero to five points with the total IPSS score ranging from 0 to 35 and its symptom severity graded as mild (0–7), moderate (8–19) and severe (20–35). The eighth question in this questionnaire, known as bother score which is scored from zero to six points, evaluates the disease-specific quality of life of the patient [5]. In the event that patients were not literate enough to complete the IPSS questionnaire, they were assisted to do so. Uroflowmetry was also done just before the prostate biopsy using the Ark Meditech Uroflowmeter, Urol 010 Model, to determine the peak flow rate (PFR).
A Mindray Digital Ultrasonic Diagnostic Imaging System, DP-20 Model with a 6.5 Hz end firing biplanar probe, was used for Trans-rectal Ultrasound Scan (TRUS) to determine the prostate volume. The maximal anteroposterior and transverse diameter were determined on transverse imaging, while the craniocaudal diameter was determined on sagittal imaging. The prostate volume was calculated using the ellipsoid formula (π/6 × anteroposterior diameter × transverse diameter × craniocaudal diameter).
All patients received intravenous Gentamicin as antibiotic prophylaxis 30 min before the procedure. Patient was placed on the left lateral decubitus position. Ten milliliters of 2% intra-rectal Lidocaine gel was instilled into the rectum. Five minutes after application of the anesthesia, an 18G Tru-cut biopsy needle mounted on a semi-automated biopsy gun (Bard® Magnum® Reusable Core Biopsy System) was inserted into the rectum to carry out a systematic sextant prostate biopsy lateral to the mid-gland. The whole procedure was performed by the same investigator using the same technique in all the patients.
IPSS, bother score and PFR were re-assessed in comparison with the baseline values, 7 and 14 days after the biopsy. Patients who developed post-biopsy acute urinary retention were also noted, and bladder decompression was carried out in them using an indwelling urethral catheter. Histological results of the patients were obtained in the second week after the biopsy. Patients were given medical therapy for lower urinary tract symptoms when negative tissue histology for malignancy was confirmed after they exited the two-week study window.
Outcome measures
The outcome measures for voiding function in this study were the development of acute urinary retention and a difference between PFR values or a variation in IPSS values at specific time points while a change in the bother score was used as a measure of alteration in the Lower Urinary Tract Symptoms-related quality of life in the patients.
Statistical analysis
G*Power Version 3.1.9.2 was used for power analysis (Franz F., Universität Keil, Germany), while data analysis was done using Statistical Package for Social Sciences (SPSS) software version 20.0 (IBM Corp., Armonk, New York, USA). The data were summarized as mean and standard deviation for continuous variables, and frequency and percentage for categorical variables. Paired samples t test was used to compare pre- and post-test data while Spearman’s and Pearson’s correlation test for the determination of the relationship between two variables. Independent samples t-test was used to compare peak flow rate between two groups. The p value was considered to be significant if < 0.05.