Stepwise Surgical Strategy for Retroperitoneal Myxofibrosarcoma with Inferior Vena Cava Reconstruction Prior to En Bloc Resection: A Case Report.

Retroperitoneal sarcomas are rare and difficult to treat. Myxofibrosarcoma (MFS), a subtype of aggressive soft tissue sarcoma, primarily arises in the extremities and trunk but rarely in the retroperitoneum. When critical vascular structures are involved, prognosis worsens, necessitating a comprehensive surgical strategy to achieve complete resection and long-term control. We present a strategic plan for achieving R0 resection of a large retroperitoneal MFS. Firstly, the entire infrahepatic inferior vena cava (IVC) was replaced with a tube graft following separation of the IVC from the aorta, division of the right renal artery, and transection of both proximal and distal IVC, including its division from the renal veins. The tumor was then removed en bloc with the IVC, right kidney, and portions of the psoas and quadriceps muscles. This case emphasized the importance of detailed preoperative planning and precise intraoperative technique to ensure complete resection in complex retroperitoneal sarcomas.