VASCULAR LEIOMYOSARCOMA ARISING FROM THE INFERIOR VENA-CAVA DIAGNOSEDBY INTRALUMINAL BIOPSY

A 61-year-old woman developed pain in the right thigh, paraplagia of t he lower extremities and lumbago in November 1996. A lumbar spine roen tgenogram showed lytic change in L2, and magnetic resonance imaging sh owed a patchy destructive lesion and compression of the dural sac from the right by a tumour. Computed tomography (CT) myelography showed a motheaten destructive lesion in L2 and projection of the tumour into t he spinal canal. Abdominal ultrasound, CT and cavography showed dilata tion of the inferior vena cava (IVC) and an intraluminal tumour about 2x2.8x4 cm in size in the IVC. The tumour arose from the IVC just bene ath the renal vein and extended to just short of the right atrium. Bot h vertebral and intraluminal biopsy materials showed the same morpholo gy, in which atypical spindle cells admired with multinucleated giant cells proliferated in a fascicular growth pattern. Neoplastic cells we re strongly positive for alpha-smooth muscle actin. We diagnosed vascu lar leiomyosarcoma arising from the IVC with metastasis to the lumbar vertebrae. Cases of vascular leiomyosarcoma diagnosed by intraluminal biopsy are rare.