Point of care parenchymal volume analyses to estimate split renal function and predict functional outcomes after radical nephrectomy.

Accurate prediction of new baseline GFR (NBGFR) after radical nephrectomy (RN) can inform clinical management and patient counseling whenever RN is a strong consideration. Preoperative global GFR, split renal function (SRF), and renal functional compensation (RFC) are fundamentally important for the accurate prediction of NBGFR post-RN.

While SRF has traditionally been obtained from nuclear renal scans (NRS), differential parenchymal volume analysis (PVA) via software analysis may be more accurate. A simplified approach to estimate parenchymal volumes and SRF based on length/width/height measurements (LWH) has also been proposed. We compare the accuracies of these three methods for determining SRF, and, by extension, predicting NBGFR after RN. All 235 renal cancer patients managed with RN (2006-2021) with available preoperative CT/MRI and NRS, and relevant functional data were analyzed. PVA was performed on CT/MRI using semi-automated software, and LWH measurements were obtained from CT/MRI images. RFC was presumed to be 25%, and thus: Predicted NBGFR = 1.25 × Global GFRPre-RN × SRFContralateral. Predictive accuracies were assessed by mean squared error (MSE) and correlation coefficients (r). The r values for the LWH/NRS/software-derived PVA approaches were 0.72/0.71/0.86, respectively (p < 0.05). The PVA-based approach also had the most favorable MSE, which were 120/126/65, respectively (p < 0.05). Our data show that software-derived PVA provides more accurate and precise SRF estimations and predictions of NBGFR post-RN than NRS/LWH methods. Furthermore, the LWH approach is equivalent to NRS, precluding the need for NRS in most patients.

Scientific reports. 2023 Apr 17*** epublish ***

Nityam Rathi, Worapat Attawettayanon, Yosuke Yasuda, Kieran Lewis, Gustavo Roversi, Snehi Shah, Andrew Wood, Carlos Munoz-Lopez, Diego A Palacios, Jianbo Li, Nour Abdallah, Jared P Schober, Marshall Strother, Alexander Kutikov, Robert Uzzo, Christopher J Weight, Mohamed Eltemamy, Venkatesh Krishnamurthi, Robert Abouassaly, Steven C Campbell

Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA., Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH, USA., Department of Surgery, Division of Urologic Surgery, University of Nebraska Medical Center, Omaha, NE, USA., Department of Urology, Oregon Health Sciences University, Portland, OR, USA., Department of Urology, Fox Chase Cancer Center, Philadelphia, PA, USA., Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA. .

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