Factors influencing urinary retention following freehand transperineal prostate biopsy: Insights from a tertiary care center study.

Abstract

Objectives: In this study, we evaluated the risk factors for urinary retention after freehand transrectal ultrasound (TRUS) guided transperineal prostate biopsy (TPB).

Patients and methods: Data from 102 cases of freehand TPB at a single institution were retrospectively collected and analyzed. All patients underwent magnetic resonance imaging (MRI)-TRUS cognitive fusion TPB using a transperineal needle guide, with systematic biopsies from 10 prostate sectors and additional MRI-guided targeted biopsies. Exclusions comprised patients with coagulation abnormalities, prior prostate surgeries including biopsy, active urinary tract infection, or a lack of pre-biopsy multiparametric MRI.

Results: 14/102 (13.72%) had urinary retention and required urethral catheterization for voiding difficulty or discomfort along with a bladder volume of ≥500 ml. Patients with retention exhibited significantly larger prostate volumes (median 75 cc vs. 40 cc; P < 0.05). Receiver operating curve analysis revealed a prostate volume threshold of 57.5 cc and a core number cutoff of 23 for predicting post-TPB urinary retention, with sensitivities of 78.57% and 85.71%, specificities of 75% and 82.95%, positive predictive values of 33.33% and 44.44%, and negative predictive values of 95.75% and 97.33%, respectively, whereas the number of biopsy cores correlated positively with the development of urinary retention (median 25 vs. 22; P < 0.05). Urinary retention was independent of the patient's age, comorbidities, presenting prostate-specific antigen levels, prebiopsy severity of lower urinary tract symptoms, and use of alpha-blockers.

Conclusion: Patients with larger prostates and higher number of biopsy cores are at a higher risk of postfreehand TPB urinary retention and should receive appropriate counselling. Targeted biopsies alone, rather than a full template, may help mitigate urinary retention in these high-risk groups.