Transurethral biopsy of the prostatic urethra is associated with final apical margin status at radical cystoprostatectomy

Purpose: Biopsy of the prostatic urethra is an integral part of clinical staging in patients prior to radical cystoprostatectomy (RC) and urinary diversion. We examined whether preoperative transurethral resection (TUR) biopsy was associated with final apical urethral margin status and hypothesized that a negative biopsy could replace intraoperative frozen section for decision making regarding the feasibility of orthotopic neobladder reconstruction. Methods: TUR biopsy, frozen section, urethrectomy, and final apical urethral margin pathologic data were extracted from the charts of men who had undergone RC at the Houston Methodist Hospital between 1987 and 2013. TUR biopsies were performed at five and seven o’clock adjacent to the verumontanum. A positive biopsy was defined as the presence of in situ or invasive urothelial carcinoma. Clinical and perioperative variables were analyzed using descriptive and inferential statistics. Results: We reviewed the medical records of 272 men. Preoperative TUR biopsies of the prostatic urethra were negative in 74% (200/272) and positive in 26% (72/272) of men. The overall incidence of apical urethral margin positivity on final pathology was 2.2% (six of 272). Four men underwent primary or secondary urethrectomy. TUR biopsy negative and positive predictive values for apical urethral margin positivity were 99.5% (95% confidence interval (CI): 97.2 to 99.9) and 6.9% (95% CI: 2.3 to 15.5), respectively. Conclusions: The incidence of a positive apical urethral margin was low in patients undergoing RC. A negative preoperative TUR biopsy of the prostatic urethra was reliably associated with a negative final margin, obviating the need for intraoperative frozen section. Furthermore, a positive biopsy was not reliably associated with final margin status. These data will aid in the counseling of patients regarding the feasibility of neobladder reconstruction.