Robotic retroperitoneal versus transperitoneal inferior vena cava thrombectomy: right-sided cases with level I-II tumor thrombus

To compare the perioperative hemodynamic consequences and oncology outcomes of robotic retroperitoneal versus transperitoneal inferior vena cava(IVC) thrombectomy(IVCT) for right renal cell carcinoma(RCC) with IVC tumor thrombus(IVCTT) that located below the first porta hepatis. Between January 2018 and June 2019, 35 patients of right RCC with IVCTT that located below the first porta hepatis underwent robotic retroperitoneal IVCT(16 patients) or transperitoneal IVCT(19 patients). We have described the procedures of transperitoneal IVCT earlier. The main procedure of robotic retroperitoneal IVCT include circumferential dissection of the IVC, sequentially clamping subhepatic IVC, the left renal vein and the caudal IVC with vessel loops, IVCT, IVC repair, radical nephrectomy(RN). The following parameters were compared between the two groups: baselines characteristic, perioperative consequences and hemodynamic changes. Retroperitoneal and transperitoneal cohorts were comparable in terms of IVC thrombus length(3.2 vs 4.0 cm), IVC block time (18 vs 16 min, p=0.64), postoperative hospital stay (6 vs 6 days, p= 0.67), postoperative complications (0 vs 0), and recurrence or metastasis rate(0 vs 0) for patients with similar baseline characteristic. The retroperitoneal cohort tended to less blood loss (160 vs 240ml,p=0.024), shorter operative time(130 vs 145min,p=0.003), lower central venous pressure(p＜0.05) and smaller diameter of IVC (p＜0.05). Robotic retroperitoneal RN and IVCT is feasible for patients of right RCC with IVCTT located below the first porta hepatis and is superior to transperitoneal IVCT in terms of bleeding control and operation time for skilled surgeons.