The role of RENAL score in predicting complications after robotic partial nephrectomy.

BACKGROUND The aim of this study is to evaluate the association between tumor complexity based on RENAL nephrometry score and complications. METHODS We retrospectively identified 2555 patients who underwent RPN for renal cell carcinoma. Major complication was defined as clavien grade≥3. The relationship between baseline demographic, clinical characteristics, perioperative and postoperative outcomes, and tumor complexity were assessed using Chi-square test of independence, Fishers exact and Kruskal Wallis test. An unadjusted and adjusted logistic regression model was used to assess the relationship between major complication and demographic, clinical characteristics, and perioperative outcomes. RESULTS There was a significant relationship between tumor complexity and WIT(p<0.001), operative time(p<0.001), estimated blood loss (p<0.001), and major complication(p=0.019). However, there was no relationship with overall complications(p=0.237) and length of stay (LOS) (p=0.085). In the unadjusted model, higher tumor complexity was associated with major complication (p=0.009). Controlling for other variables, there was no significant difference between major complication and tumor complexity (low vs. moderate, p=0.142 and high, p=0.204). LOS (p <0.001) and operative time (p=0.025) remained a significant predictor of major complication in the adjusted model. CONCLUSIONS Tumor complexity is not associated with an increase in overall or major complication rate after RPN. Experience in high-volume centers is demonstrating a standardization of low complications rates after RPN independent of tumor complexity.