Retroperitoneal sarcomas are rare neoplasms . They frequently reach a very large size and invade adjacent organs before they are detected. Involvent of the inferior vena cava is uncommon. Distant metastases are a late feature. The mainstay of treatment is compartmental resection and contiguous organ resection. We report two cases of right-sided massive primary retroperitoneal leiomyosarcoma in pauci symptomatic women. In both cases treatment consisted of radical surgery. En bloc resection of the tumor and surrounding tissues and organs as well as part of the right wall of the subrenal IVC. To close the wall defect direct suture repair was used resulting in a reduced caliber but no hemodynamic sequelae or endoluminal thrombi. All the resection margins, including the inferior vena cava wall, were negative. The postoperative course was unremarkable and caval blood flow was optimal. The current gold standard treatment for retroperitoneal sarcoma is en bloc multivisceral resectionresection.