BACKGROUND: Leiomyosarcoma is the most common primary malignancy of the inferior vena cava (IVC), and represents approximately 10% of primary retroperitoneal sarcomas. Leiomyosarcoma presents with non-specific symptoms, including abdominal pain or back pain. There is an increased incidence in immunosuppressed individuals.

CASE REPORT: An unusual presentation of IVC leiomyosarcoma is reported in a 46-year-old female patient infected with human immunodeficiency virus (HIV) who was on highly active antiretroviral therapy (HAART) and who had a normal CD4 count of 934, who presented with back pain. Magnetic resonance imaging (MRI) of the lumbar spine showed a mass of the IVC. Initial computed tomography (CT)-guided biopsy of the IVC mass was non-diagnostic. An IVC filter was inserted, and the patient was discharged home, but 20 days later, she returned to the hospital with worsening right flank pain. Laboratory tests showed acute renal failure, and a repeat CT scan showed IVC thrombus extending 5 cm superiorly. When compared with the previous CT, there was an extension of thrombus into both renal veins. Histopathology of a transjugular needle core biopsy showed a moderately differentiated leiomyosarcoma. The patient was transferred to a multidisciplinary sarcoma center for surgical resection, chemotherapy, and radiation therapy.

CONCLUSIONS: This report is of a rare case of IVC leiomyosarcoma in a middle-aged HIV-positive woman with a normal CD4 count. Leiomyosarcoma of the IVC is extremely rare, is often detected when advanced, and has a poor prognosis. This case report describes the clinical, imaging, surgical and histopathological findings of leiomyosarcoma of the IVC.

Keywords: CD4 Lymphocyte Count, Epstein-Barr Virus Infections, HIV, Leiomyosarcoma, Vena Cava, Inferior