Perioperative and oncologic outcomes of minimally-invasive surgery for renal cell carcinoma with venous tumor thrombus: a systematic review and meta-analysis of comparative trials

Background: The present study aimed to conduct a pooled analysis to compare the perioperative and oncologic outcomes of minimally-invasive radical nephrectomy with tumor thrombus (MI-RNTT) with open radical nephrectomy with tumor thrombus (O-RNTT). Methods: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Four electronic databases (PubMed, Embase, Web of Science, and the Cochrane Library database) were systematically searched to identify relevant studies published in English up to December 2022. The primary outcomes were perioperative results, complications, and oncologic outcomes. Review Manager 5.4 was used for this analysis. Results: In total, eight retrospective trials with a total of 563 patients were included. Compared to O-RNTT, MI-RNTT had shorter hospitalization time [weighted mean difference (WMD) -3.58 days, 95% CI: -4.56 to -2.59; P<0.00001), lower volumes of blood loss (WMD -663.32 ml, 95% CI: -822.22 to -504.42; P<0.00001), fewer transfusion rates (OR 0.18, 95% CI: 0.09-0.35; P<0.00001), fewer overall complications (OR 0.33, 95% CI: 0.22-0.49; P<0.00001), and fewer major complications s (OR 0.49, 95% CI: 0.24-1.00; P=0.05). However, operative time, intraoperative complications, mortality rate (intraoperative, within 30 days, and total mortality), overall survival, recurrence-free survival, and cancer-specific survival did not significantly differ between the two groups. Conclusions: MI-RNTT possesses more benefits than O-RNTT in terms of length of hospital stay, blood loss, and complications and provides comparable mortality rates and oncologic outcomes. However, more comprehensive and rigorous research is warranted to further validate the outcomes, which should include a larger sample size and comprehensive data from high-volume medical centers.