Rates and Predictors of Perioperative Complications in Cytoreductive Nephrectomy: Analysis of the Registry for Metastatic Renal Cell Carcinoma

Background Cytoreductive nephrectomy (CN) plays an important role in the treatment of a subgroup of metastatic renal cell carcinoma (mRCC) patients. Objective We aimed to evaluate morbidity associated with this procedure and identify potential predictors thereof to aid patient selection for this procedure and potentially improve patient outcomes. Design, setting, and participants Data from 736 mRCC patients undergoing CN at 14 institutions were retrospectively recorded in the Registry for Metastatic RCC (REMARCC). Outcome measurements and statistical analysis Logistic regression analysis was used to identify predictors for intraoperative, any-grade (AGCs), low-grade, and high-grade (HGCs) postoperative complications (according to the Clavien-Dindo classification) as well as 30-d readmission rates. Results and limitations Intraoperative complications were observed in 69 patients (10.9%). Thrombectomy (odds ratio [OR] 1.38, 95% confidence interval [CI] 1.08–1.75, p = 0.009) and adjacent organ removal (OR 2.7, 95% CI 1.38–5.30) were significant predictors of intraoperative complications at multivariable analysis. Two hundred seventeen patients (29.5%) encountered AGCs, while 45 (6.1%) encountered an HGC, of whom 10 (1.4%) died. Twenty-four (3.3%) patients had multiple postoperative complications. Estimated blood loss (EBL; OR 1.49, 95% CI 1.08–2.05, p = 0.01) was a significant predictor of AGCs at multivariable analysis. CN case load (OR 0.13, 95% CI 0.03–0.59, p = 0.009) and EBL (OR 2.93, 95% CI 1.20–7.15, p = 0.02) were significant predictors solely for HGCs at multivariable analysis. Forty-one patients (11.5%) were readmitted within 30 d of surgery. No significant predictors were identified. Results were confirmed in a subanalysis focusing solely on patients treated in the contemporary targeted therapy era. Conclusions Morbidity associated with CN is not negligible. Predictors of high-grade postoperative morbidity are predominantly indicators of complex surgery. EBL is a strong predictor of postoperative complications. CN case load correlates with lower high-grade morbidity and highlights the benefit of centralization of complex surgery. However, risks and benefits should be balanced when considering CN in mRCC patients. Patient summary We studied patients with metastatic renal cancer to evaluate the outcomes associated with the surgical removal of the primary kidney tumor. We found that this procedure is often complex and adverse events are not uncommon. High intraoperative blood loss and a small number of cases performed at the treating center are associated with a higher rate of postoperative complications.