Login to Access Video or Poster Abstract: MP49-17
Sources of Funding: None

Introduction

Minimization or reducing on-clamp time during PN has led to alternative technical modifications. The concept of off-clamp PN aims to avoid the ischemic injury on the healthy parenchyma. The purpose of this study was to compare the outcomes of off-clamp to on-clamp approach during robot-assisted partial nephrectomy (RAPN)._x000D_

Methods

Retrospective study of 940 patients who underwent RAPN between 2007 and 2016 for cT1a tumors using on-clamp or off-clamp approaches. We matched the patients in terms of confounding variables. Overall, 309 patients with on-clamp technique were matched to 103 patients with off-clamp technique. We compared the clinico-pathological characteristics, perioperative morbidity and late functional outcomes between the propensity score matched groups. The excisional volume loss was calculated on pathology specimen. Postoperative e-GFR was calculated between 3 to 12 months after PN.

Results

There were no difference in clinico-pathological characteristics between the 2 matched groups. While operative time (p=0.4), estimated blood loss (p=0.28), Clavien grade III-V complications (p=0.8), surgical reoperation (p=1), 30-day readmission (p=1) positive surgical margin (5.5% vs. 5.8%, p =0.9) were comparable between the 2 groups, there were significant difference in excisional volume loss (median, 7.08 vs. 3.51 cm3, p<0.01), e-GFR decline (median, -9.7 vs. -2.2 ml/min/1.73m2, p<0.01), percent of e-GFR preservation (median, 87% vs. 97%, p<0.01), and CKD upstaging (36.5% vs. 23.3%, p=0.01) in favor of off-clamp group. Excisional volume loss (p=0.01), off-clamp approach (p=0.01), and age (p=0.02) were predictors of renal function preservation, whereas excisional volume loss (OR=1.035, CI 95% [1.015-1.06], p<0.01) predicted CKD upstaging.

Conclusions

RAPN for selected renal mass using off-clamp approach offered renal functional advantage over on-clamp, without adding morbidities. Excisional volume loss, off-clamp approach, and age were independent predictors of renal function preservation.

Funding

None