Elsevier

Urology

Volume 84, Issue 5, November 2014, Pages 1128-1133
Urology

Oncology
Assessment of Outcomes in Partial Nephrectomy Incorporating Detailed Functional Analysis

https://doi.org/10.1016/j.urology.2014.07.008Get rights and content

Objective

To assess perioperative morbidity and margins after conventional clamped partial nephrectomy (PN) while also using volumetric analysis to differentiate the contributions of parenchymal volume loss and recovery from ischemia.

Materials and Methods

The study analyzed 163 patients who underwent PN with appropriate studies to allow analysis of function and parenchymal mass specifically in the operated kidney. Recovery from ischemia (glomerular filtration rate saved/volume saved) would be 100% if all nephrons recovered from ischemia. Precision (postoperative parenchymal volume/predicted parenchymal volume, presuming loss of a 5-mm rim of parenchyma related to excision and reconstruction) reflects efforts to optimize the amount of vascularized parenchyma saved with the PN. Trifecta was defined as negative margins, no Clavien grade 3-5 or urologic complications, and both recovery ≥80% and precision ≥80%.

Results

An open procedure was performed in 82 patients (50%), and 59 (36%) had a solitary kidney. Warm ischemia was used in 96 patients (59%). The RENAL nephrometry score (radius, exophytic/endophytic properties of the tumor, nearness of tumor deepest portion to the collecting system or sinus, anterior/posterior descriptor, and the location relative to polar lines) was intermediate in 74 (45%) and high complexity in 38 (23%). Median recovery from ischemia was 95% and was ≥80% in 143 patients (88%). Median precision of excision/reconstruction was 93% and was ≥80% in 138 patients (85%). All tumors had negative surgical margins. Perioperative complications occurred in 13 patients (9%). Trifecta was achieved in 113 patients (69%). Multivariable analysis identified solitary kidney as the only significant predictor of trifecta.

Conclusion

Given careful patient selection and commensurate surgical expertise, excellent outcomes can be obtained with conventional clamped PN. Analysis of parenchymal volumes is necessary to facilitate comprehensive evaluation of functional outcomes after PN, allowing differentiation of nephron loss vs failure to recover from ischemia.

Section snippets

Materials and Methods

This study was approved by the Cleveland Clinic Institutional Review Board.

Results

Table 1 provides patient characteristics for the total cohort, which appears to be representative of conventional PN populations. Median patient age at surgery was 62 years, and 64% were male. RENAL-NS distribution included 45% with intermediate score (7-9) and 23% with high complexity score (10-12) tumors. Open surgery was performed in 82 patients (50%), and minimally invasive surgery (MIS) in 81 (49%). Cold ischemia was applied in 41% of patients (median, 27 minutes) and warm ischemia in 59%

Comment

The main objectives of PN are obtaining oncologic control, minimizing morbidity, and optimizing preservation of renal function. There are now a multitude of surgical approaches to PN, and assessment of outcomes should take all of these considerations into account. Recent focus has been on functional outcomes and efforts to avoid exacerbation of pre-existing chronic kidney disease, which can be associated with progressive decline of renal function, morbid cardiovascular events, and increased

Conclusion

Presuming careful patient selection, adequate surgical expertise, and judicious use of hypothermia, excellent outcomes can be achieved with clamped PN, whether by open or MIS approaches. A comprehensive evaluation of functional outcomes after PN, including differentiation of nephron loss vs failure to recover from ischemia, should facilitate more informative comparison of outcomes after this procedure.

References (24)

Cited by (6)

Financial Disclosure: The authors declare that they have no relevant financial interests.

View full text