Postprostatectomy incontinence (PPI), defined as involuntary urine loss following radical prostatectomy (RP), is a well-recognized and bothersome complication. Platelet-rich plasma (PRP) has been utilized for tissue repair and regeneration. This study aimed to evaluate the therapeutic efficacy and durability of PRP injections into the urethral sphincter for managing PPI.

A total of 71 patients with PPI refractory to conservative treatments were prospectively enrolled. Each patient received monthly PRP injections into the urethral sphincter for four consecutive months. The primary endpoint was the Global Response Assessment (GRA) score after treatment, along with the identification of predictive factors for a successful outcome. Secondary endpoints included changes in the stress urinary incontinence (SUI) visual analog scale (VAS), Urogenital Distress Inventory (UDI-6), Incontinence Impact Questionnaire (IIQ-7), pad usage, and urodynamic parameters, assessed from baseline to the end of follow-up (3 months).

The mean age of the patients was 71.0 ± 7.2 years (range: 53–87), with a mean SUI duration of 35.5 ± 36.8 months (range: 12–180). After four PRP injections, the mean GRA score was 1.21 ± 1.14 (range: -1 to +3). Significant improvements were observed in the VAS score for SUI (from 7.1 ± 1.8 to 5.2 ± 2.3, p < 0.001), UDI-6 score (from 5.38 ± 2.3 to 3.86 ± 2.3, p < 0.001), and abdominal leak point pressure (from 109.42±46.9 to 133.9±65.9 cmH₂O, p = 0.014). The increase in abdominal leak point pressure (ALPP) was significantly greater in the successful group (49.3± 78.3, 4.9± 52.4; p= 0.028). Additionally, cystometric bladder capacity (CBC) was identified as a significant predictor of a successful outcome (p = 0.047).

PRP injections into the urethral sphincter significantly reduced SUI severity, demonstrating their potential as an effective and durable novel treatment for PPI. Moreover, patients with a greater CBC tend to achieve better treatment outcomes.