Centrality angle is a novel nephrometry score to predict tumor complexity and perioperative outcomes for partial nephrectomy

To propose the centrality angle (C-angle) as a novel simple nephrometry score for the evaluation of tumor complexity and prediction of perioperative outcomes in nephron-sparing surgery (NSS) for renal tumors. The analysis was based on 174 patients who underwent robot-assisted partial nephrectomy retrospectively. C-angle was defined as the angle occupied by the tumor from the center of the kidney in the coronal CT images. Other nephrometry scores were calculated and compared with C-angle. Associations between C-angle and perioperative outcomes were examined. Significant differences were found in C-angle between tumors greater and less than 4 cm, exophytic and endophytic tumors, and hilar and non-hilar tumors. C-angle was correlated with other nephrometry scores, including RENAL, PADUA, and C-index. Significant positive correlations with WIT, operation time, and EBL, and significant negative correlations with preserved eGFR. C-angle could predict perioperative complications. Patients with a C-angle > 45° had worse perioperative outcomes, including longer operative time, longer WIT, lower rate of preserved eGFR, and complications. C-angle can be used to evaluate the complexity of renal tumors and predict perioperative outcomes. C-angle can potentially be used for decision-making in the treatment of patients and to guide surgical planning of NSS.