Resection and Reconstruction of the Inferior Vena Cava Using a Tunneled Peritoneal Graft for Renal Tumor With Thrombus: Venous Compensation via the Azygos Vein Following Early Graft Occlusion.

Inferior vena cava (IVC) invasion by tumor thrombus poses a significant surgical challenge, often requiring vascular reconstruction. Standard methods, including prosthetic and autologous vein grafts, have limitations such as infection risks, anticoagulation demands, and increased costs. We present the case of a 66-year-old male with a right renal tumor (T3bN0M0, Neves Zincke II) and gross hematuria, who underwent radical nephrectomy with open thrombectomy. During surgery, extensive IVC invasion was identified, and a 12×7 cm autologous peritoneal graft was used for IVC reconstruction in the absence of other graft options. Postoperative imaging revealed initial patency; however, near-total graft occlusion was observed by day 15, with asymptomatic compensation via the azygos vein. Pathology revealed clear cell renal cell carcinoma with sarcomatoid and rhabdoid features (ISUP/WHO grade 4) and negative surgical margins, and adjuvant pembrolizumab was initiated. This case highlights the utility of autologous peritoneal grafts as an emergency solution when conventional options are unavailable; however, this treatment also carries potential complications. Further research is needed to optimize graft durability and improve long-term outcomes in vascular reconstructions involving the IVC.