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

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.

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.

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.

SL-ocRPN is safe and effective and represents a feasible alternative to RR-ocRPN in selected cT1-2N0M0 renal tumors.