Surgical Management of Tumours Invading the Inferior Vena Cava: A Delphi Consensus Document.

Objective: There is a lack of information and consistency in the treatment of retroperitoneal malignancy involving the inferior vena cava (IVC). The aim of this study was to establish an expert consensus on the surgical management of tumours involving the IVC.

Methods: Fourteen experts participated in this three round Delphi project. The survey was conducted from 1 January 2023 to 15 December 2023. Consensus was defined as 70% agreement with a Cronbach's α of 0.05.

Results: All experts completed the first round, and the response rates in the second and third rounds were 92% and 86%, respectively. Consensus was reached on several key points. Abdominal computed tomography (CT) was identified as the gold standard imaging method for assessing tumours invading the IVC. CT guided core needle biopsy was preferred for tissue sampling. Experts agreed that the suprarenal IVC should be reconstructed, whereas a chronically occluded IVC with intact collateral circulation should not. Thrombectomy was indicated for malignant thrombi not involving the vessel wall; otherwise, IVC resection was recommended. A ringed ePTFE (expanded polytetrafluoroethylene) prosthesis was the preferred graft material for interposition. Use of an IVC filter to prevent tumour embolisation and the creation of an arteriovenous fistula after IVC resection were not recommended. Post-operative thrombosis prevention should include therapeutic heparinisation and a mechanical compression device, and routine post-operative CT angiography was recommended.

Conclusion: Based on scarce data from the literature and experience of international experts, this document will help clinicians in the decision making process when planning the treatment of retroperitoneal tumours involving the IVC.