History and clinical findings: In a 34-year-old woman who underwent ultrasound investigation because of recurrent pyelonephritis a space-occupying lesion in the liver was an incidental finding. Computed tomography (CT) and magnetic resonance imaging (MRI) confirmed a tumour in segment I of the liver. The patient had been on contraceptives for 12 years. She had no symptoms.
Investigations: Laboratory tests, including tumour markers, were unremarkable. Diagnostic tests to exclude malignant tumour with metastases were negative (thyroid scintigraphy, mammography, coloscopy and gastroscopy). Further tests (ultrasound, coeliaco-mesentericography, hydro-CT and spiral CT, MRI) revealed a tumour, 5 x 4 x 4 cm, in segment I of the liver, most likely an adenoma. Surgical intervention was indicated by the size and questionable malignancy of the tumor.
Treatment and course: At operation a tumour was found which originated from the inferior vena cava (IVC) and displaced segment I of the liver. The tumour was resected and the venous wall reconstructed with a Goretex patch. Histological examination indicated a poorly differentiated leiomyosarcoma of the IVC. Adjuvant radiotherapy was undertaken postoperatively. There has been no evidence of recurrence after 10 months.
Conclusions: Leiomyosarcoma of the IVC can be mistaken, both by ultrasound and tomographic diagnostic procedures, for a tumour in segment I of the liver, especially an adenoma. A leiomyosarcoma of the IVC should be included in the differential diagnosis of an hepatic tumour that lies close to segment I of the liver.