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BACKGROUND Robot-assisted retrohepatic inferior vena cava (IVC) thrombectomy (RA-R-IVCTE) has been reported only for limited series. OBJECTIVE To describe in detail the techniques for RA-R-IVCTE with regard to the relationship of a proximal thrombus to either the first porta hepatis (FPH) or second porta hepatis (SPH). DESIGN, SETTING, AND PARTICIPANTS From May 2013 to July 2016, 22 patients with R-IVC tumor thrombi were admitted to our hospital. SURGICAL PROCEDURE RA-R-IVCTE was performed using the Rummel tourniquet technique. For a proximal thrombus inferior to the FPH, we ligated some short hepatic veins (SHVs; typically 1-3). For a thrombus between the FPH and SPH, we mobilized the right lobe of the liver from the IVC by ligating additional SHVs. For a thrombus near or above the SPH but below the diaphragm, we mobilized both the right and left lobes of the liver to obtain high proximal control of the suprahepatic and infradiaphragmatic IVC, and simultaneously clamped the FPH. MEASUREMENTS Detailed techniques were described for various scenarios and perioperative outcomes were recorded. RESULTS AND LIMITATIONS The median operation time was 285min (interquartile range [IQR] 191-390). Intraoperative estimated blood loss was 1350ml (IQR 1000-2075ml). Some 63.6% of patients required an intraoperative blood transfusion and 68% were transferred to the intensive care unit after surgery. Grade IV complications developed in five cases. Vascular injuries (4 cases) were treated with intraoperative endoscopic sutures. An intestinal fistula was found on postoperative day 7 in one case; treatment with gastrointestinal decompression and drainage resolved the condition by 1 mo. CONCLUSIONS Even though the risks involved are high, RA-R-IVCTE is feasible for selected patients. The FPH/SPH is an important boundary landmark for RA-R-IVCTE. The location of proximal IVC tumor thrombi in relation to the FPH or SPH should determine the technique used. PATIENT SUMMARY Robot-assisted thrombectomy for retrohepatic inferior vena cava tumor thrombus is feasible in selected patients.