A systematic review and meta-analysis of clinicopathologic factors linked to oncologic outcomes for renal cell carcinoma with tumor thrombus treated by radical nephrectomy with thrombectomy

Background: There remain discrepancies over the factors that influence oncologic outcomes after radical nephrectomy with thrombectomy (RNTE). To assess significant predictors of oncologic outcomes after RNTE from a systematic review and meta-analysis. Methods: A comprehensive search of PubMed, Embase, Cochrane Library and Web of Science was performed to identify eligible studies. The endpoints included cancer-specific survival (CSS), overall survival (OS), and recurrence-free survival (RFS). A formal meta-analysis was performed for studies containing non-metastatic and metastatic tumors. Additionally, a sensitivity analysis including the subgroup of studies containing non-metastatic tumors only was conducted. Cumulative analyses of hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) were conducted. Results: Overall, 35 retrospective studies of low to moderate risk of bias including 11,929 patients were included. The results indicated that large tumor size, high Fuhrman grade, tumor necrosis, positive lymph node, and metastasis at surgery were adverse significant predictors for both CSS and OS. Also, IVC tumor thrombus, sarcomatoid differentiation, perinephretic fat invasion, and adrenal gland invasion were associated with poor CSS. In the subset of non-metastatic patients, the significant predictors were clinical symptom, thrombus level, Fuhrman grade and adrenal gland invasion for CSS; thrombus consistency, Fuhrman grade and tumor necrosis for OS; tumor size, Fuhrman grade and perinephretic fat invasion for RFS. Conclusions: A meta-analysis of available data identified significant prognostic factors of CSS, OS and RFS that should be systematically evaluated to propose a risk-adapted approach to postoperative patient counseling, risk stratification, and therapy selection.