Sutureless Purely Off-clamp Robotic Partial Nephrectomy: Evidence from a Randomized Controlled Noninferiority Trial

BACKGROUND AND OBJECTIVE: The sutureless (SL) purely off-clamp robotic partial nephrectomy (ocRPN) technique has been proposed to minimize postoperative functional damage. We assessed whether this approach is noninferior to renorrhaphy (RR) in terms of surgical quality. METHODS: Patients with cT1-2N0M0 renal tumors were randomly assigned to SL or RR-ocRPN within a single-center, single-surgeon randomized controlled trial (NCT06846112). A covariate-adaptive 1:1 randomization algorithm ensured balance between treatment arms for age, sex, baseline renal function, and tumor surgical complexity. The primary endpoint was Trifecta achievement at discharge. A prespecified noninferiority test (margin -10%) compared Trifecta rates using one-sided testing and confidence intervals. Secondary outcomes were descriptively analyzed and compared between study arms. Recurrence-free survival (RFS) was estimated using the Kaplan-Meier method. KEY FINDINGS AND LIMITATIONS: Among 248 patients, baseline characteristics were balanced. Trifecta was achieved in 93% and 95% of cases (absolute difference -2.4%; 90% confidence interval CI -7.4%-2.6%), meeting the criterion for noninferiority (one-sided p = 0.006). Blood transfusions (2.4% vs 0%) and acute kidney injury (1.6% in both groups) were rare. Nine urinary fistulae occurred overall, all managed with temporary stenting; rates were higher in the SL group but not statistically significant (p = 0.08). Renal function remained stable up to 12 mo, and 1-yr RFS was 99% in all cohorts. Limitations include single-center design, surgeon expertise, and short oncologic follow-up. CONCLUSIONS AND CLINICAL IMPLICATIONS: SL-ocRPN is safe and effective and represents a feasible alternative to RR-ocRPN in selected cT1-2N0M0 renal tumors.