Hypothesis / aims of study
To objectively evaluate the physiological basis of early urinary continence recovery after single-port transvesical robot-assisted radical prostatectomy (SP-TVRP) by assessing postoperative bladder storage, voiding function, and urethral sphincter integrity using formal urodynamic testing.
Study design, materials and methods
This prospective case-series conducted SP robotic transvesical radical prostatectomy and UDS 3 months after surgery. The inclusion criteria were as follows: 1) prostate cancer patients aged ≥ 40 years; 2) patients with localized or locally advanced prostate cancer who were candidates for radical prostatectomy; and 3) patients eligible for general anesthesia. The exclusion criteria were as follows: 1) patients with severe benign prostatic hyperplasia with a prostate volume of ≥ 80 cc; 2) patients with a history of previous surgery or procedure for benign prostatic hyperplasia; 3) patients unable to void normally due to neurological issues; 4) patients with lymph node metastasis; 5) patients with urethral stricture; and 6) patients who had been treated with neoadjuvant androgen deprivation therapy.
Results
Urodynamic evaluation demonstrated preserved bladder storage function, with a median maximum cystometric capacity of 450 mL and median bladder compliance of 64 mL/cmH₂O. Detrusor overactivity was identified in only one patient (9.1%). Median BOOI and BCI values were 16 and 93, respectively, indicating predominantly non-obstructed or equivocal voiding physiology. Urethral sphincter function was largely intact, reflected by a median maximum urethral closure pressure of 58 cmH₂O and negative abdominal leak point pressure testing in 72.7% of patients. Early continence recovery was favorable, with 36.4%, 54.5%, and 90.9% of patients being pad-free immediately, at 1 month, and at 3 months postoperatively, respectively. The positive surgical margin rate was 45.5%, attributed to the learning curve of intravesical single-port access.
Interpretation of results
SP-TVRP preserves key anatomical and physiological mechanisms of urinary continence, providing rapid functional recovery supported by objective urodynamic evidence. Despite a higher early positive surgical margin rate, likely related to the learning curve, SP-TVRP demonstrates strong potential as a functionally advantageous prostatectomy approach for selected patients. Further comparative studies with long-term oncologic and functional assessments are warranted to define its definitive role in contemporary prostate cancer surgery.