Inferior vena cava (IVC) sarcomas are rare, aggressive tumours with a poor prognosis. Surgical resection is the only potentially curative treatment, but it can be challenging due to extensive tumour involvement and associated complications. We present the case of a woman in her 30s diagnosed with a retroperitoneal mass infiltrating the IVC, liver and diaphragm. Biopsy confirmed the diagnosis of locally advanced IVC leiomyosarcoma. The patient underwent neoadjuvant chemotherapy and radiotherapy, followed by surgical resection of the tumour, the involved organs and a segment of the IVC. Vascular reconstruction was performed using a cadaver vein graft. Despite the aggressive nature of IVC sarcomas and the challenges associated with their management, surgical resection remains the primary goal. Long-term follow-up is crucial for monitoring recurrence, which is common in these patients.