Cephalic inferior vena cava non-clamping technique versus standard procedure for robot-assisted laparoscopic level II–III thrombectomy: a prospective cohort study

Background: Renal tumour can invade the venous system and ~4–10% patients with renal tumour had venous thrombus. Although the feasibility of robot-assisted laparoscopic inferior vena cava thrombectomy (RAL-IVCT) in patients with inferior vena cava (IVC) thrombus has been validated, the wide application is still a challenge due to the complexity of IVC control. The objective was to describe our novel cephalic IVC non-clamping technique and to compare the outcomes versus standard RAL-IVCT. Materials and methods: A prospective single-centre cohort containing 30 patients with level II–III IVC thrombus was established since August 2020. Fifteen patients underwent cephalic IVC non-clamping approach and 15 patients received standard RAL-IVCT. The authors decided the surgical technique according to the echocardiographic assessment of the right heart and IVC. Results: The non-clamping group had less operative time (median 148 versus 185 min, P=0.04), and lower Clavien-grade II complication rate (26.7% versus 80.0%, P=0.003). The median intraoperative blood loss were 400 ml [interquartile range (IQR) 275–615 mL] and 800 ml (IQR 350–1300 ml), respectively (P=0.05). The most common complication in standard RAL-IVCT group was liver dysfunction. No gas embolism, hypercapnia or tumour thrombus dislodgment occurred in non-clamping group. After a median follow-up of 17.0 months (IQR 13.5–18.5 months) and 15.5 months (IQR 13.0–17.0 months), two patients (16.7%) in the non-clamping group and 3 patients (20.0%) in the standard RAL-IVCT group died (hazard ratio 0.59, 95% CI 0.10–3.54, P=0.55). Conclusions: The cephalic IVC non-clamping technique can be performed safely with acceptable surgical outcomes and short-term oncologic outcomes in patients with level II–III IVC thrombus. Compared with standard procedure, it had less operative time and lower complication rate.