Laparoscopy and Robotics Higher RENAL Nephrometry Score is Predictive of Longer Warm Ischemia Time and Collecting System Entry During Laparoscopic and Robotic-assisted Partial Nephrectomy Wesley A. Mayer, Guilherme Godoy, Judy M. Choi, Alvin C. Goh, Shelly X. Bian, and Richard E. Link OBJECTIVE To investigate the predictive value of the RENAL Nephrometry Score (RNS) on operative outcomes during both laparoscopic partial nephrectomy (LPN) and robotic-assisted partial nephrectomy (RPN). METHODS We reviewed 67 consecutive patients with suspicious renal lesions and available radiographic data who underwent LPN or RPN by a single surgeon. Data included operative type, body mass index (BMI), gender, age, and side of tumor. RNSs were recorded using either magnetic resonance imaging or computed tomography scans. Warm ischemia time (WIT), estimated blood loss (EBL), and collecting system entry (CSE) were the endpoints for the analyses. RESULTS Total RNS entered as a continuous or dichotomous variable (7 or 7), R-score, and N-score were independent predictors of WIT on multivariable analyses (P .001, P  .001, P  .026, and P .01, respectively). The total RNS and N-score were predictive of CSE in univariate analysis (P .001). Neither total RNS nor its individual components were predictive of EBL. CONCLUSION Total RNS, as well as the N- and R-scores, can help predict both longer WIT and CSE during LPN and RPN. The RNS and its individual components may be useful in the preoperative planning and counseling of patients undergoing LPN or RPN. UROLOGY 79: 1052–1056, 2012. © 2012 Elsevier Inc. P artial nephrectomy is now recognized as oncologi- cally equivalent to radical nephrectomy for treat- ing small renal masses, and it carries a decreased risk of chronic kidney disease, which has been associated with hospitalization, cardiovascular disease, and death. 1-4 Laparoscopic partial nephrectomy (LPN) can be per- formed with oncological and functional outcomes similar to open partial nephrectomy for small renal masses. 5,6 Surgeons often subjectively analyze radiographic tumor features to determine the technical feasibility of partial nephrectomy for a particular mass. In 2009, Kutikov and Uzzo published the RENAL Nephrometry Score (RNS) in an attempt to create a consistent reproduc- ible system for quantitating the pertinent anatomic characteristics of a localized renal mass relevant to surgical decision-making. 7 Their intent was that nephrometry score might offer a standard for compar- ison of care patterns and published data from surgical series. Since its introduction, there have been 26 peer- reviewed publications using and/or analyzing RNS; however, only one has examined the predictive value of RNS on surgical outcomes in patients undergoing robotic-assisted partial nephrectomy (RPN) 8 and none have examined the predictive value of the individual components of the nephrometry score on outcomes. The purpose of this study was to investigate the pre- dictive value of RNS and its individual components on operative outcomes during both RPN and LPN. MATERIAL AND METHODS Between September 2005 and August 2010, 93 patients with renal masses underwent completed LPN or RPN by a single surgeon. A retrospective review was performed and data were entered in a database approved by our institutional review Funding Support: Aventis Urologic Oncology Fellowship—Hope Foundation/SWOG (to Guilherme Godoy). From the Scott Department of Urology, Baylor College of Medicine, Houston, TX Reprint requests: Wesley A. Mayer, M.D., The Scott Department of Urology, Baylor College of Medicine, 6620 Main Street, Suite 1325, Houston, TX 77030. E-mail: wamayer@tmhs.org Submitted: October 4, 2011, accepted (with revisions): January 27, 2012 1052 © 2012 Elsevier Inc. 0090-4295/12/$36.00 All Rights Reserved doi:10.1016/j.urology.2012.01.048