Comparison of single-stage and two-stage transverse preputial island flap urethroplasty for severe hypospadias with long urethral defect length: A prospective multicenter study

Purpose: To find the cut-off value of urethral defect length (UDL) to guide the choice of single‑stage or two‑stage transverse preputial island flap urethroplasty (TPIFU). Methods: We prospectively collected the data of patients with severe hypospadias underwent single-stage and two-stage TPIFU at fifteen tertiary referral institutions from 2019 to 2020. The receiver operating characteristic (ROC) analyzed the cut-off value of UDL to predict postoperative complications with single-stage TPIFU. We extracted patients with long UDL (longer than the cut-off value) in the single-stage and two-stage TPIFU, comparing the postoperative complications. Results: A total of 536 patients included 483 underwent single-stage TPIFU and 53 underwent two-stage TPIFU were collected. The ROC analyzed the cut-off value of UDL was 3.5 cm. 169 patients with long UDL (longer than 3.5 cm) were extracted from all 536 patients, with 126 underwent single-stage TPIFU (single-stage group) and 43 underwent two-stage TPIFU (two-stage group). In the single-stage group, complications occurred in 62 (49.2%) patients, including 34 (27.0%) with urethrocutaneous fistula, 21 (16.7%) with urethral stricture, and 25 (19.8%) with diverticulum. In the two-stage group, total complications occurred in four (9.3%), there were both two (4.7%) with urethral stricture and diverticulum, and no urethrocutaneous fistula was recorded. Conclusion: Our results show that two-stage TPIFU can significantly reduce the incidence of postoperative complications for hypospadias with UDL longer than 3.5 cm, especially urethrocutaneous fistula and diverticulum.