RESUMEN
BACKGROUND: Leiomyosarcoma is a malignant neoplasm and can originate within major abdominal veins, including the inferior venacava (IVC). CASE: A 45-year-old woman presented with upper abdominal pain and a mass lesion in the liver and within the lumen of the IVC. A diagnosis of primary leiomyosarcoma of the IVC was made by using imaging techniques,fine needle aspiration cytology and histopathologic examination of the resected specimen. CONCLUSION: In patients presenting with vague upper abdominal pain and radiologic features of a hepatic mass extending to major veins, the rare possibility of primary leiomyosarcoma of the IVC shoald he considered and investigated by both fine needle aspiration cytology and intraoperative histology. Early surgical intervention and/or postoperative chemotherapy and radiotherapy are associated with improved survival.