Primary leiomyosarcoma (LMS) of the hepatic vena cava is a rare malignancy that has only been published in case reports. Only a few cases with successful R0 resection have been reported in the literature. We report 2 similar cases of extended primary LMS of the intrahepatic inferior vena cava (IVC). Both patients previously underwent operations in nonspecialized centers that resulted in inadequate tumor resection. After admission to a high-volume center focusing on the treatment of patients with sarcoma, R0 resection was feasible with a multimodal therapeutic treatment approach. Radical complete tumor resection was achieved by means of extended right-sided hemihepatectomy (segments V-VIII and I), en bloc resection, and prosthetic replacement of the IVC and nephrectomy in 1 patient. Both patients are currently tumor-free and healthy 6 months postoperatively. Patients with such complex tumors should be referred to centers with specialized surgeons who can preoperatively estimate whether complete resection may be possible and who are capable of performing such delicate interventions.