Lumbar spinal extradural angiolipoma: case report and review of the literature

Abstract

Angiolipomas in the lumbar spinal region are extremely rare. The present report describes the identification of such a tumor and its removal, and discusses the tumor characteristics and prognosis. A 74-year-old woman was presented with a 5-month history of lower back pain. Severe radiculopathy was experienced in the left leg for 5 days prior to the presentation, and there were no neurological deficits. Magnetic resonance (MR) images showed an approximately 3.5 cm heterogeneously enhanced and elongated mass at the left L5-S1 level. A portion of the mass appeared with high signal intensity on T2-weighted MR images, with low signal intensity on T1-weighted images, and with high signal intensity on T1 fat suppression enhancement images. Resection of the tumor was approached via an L5 and S1 laminectomy. A fibrous sticky yellowish hypervascular tumor was identified. Histological study revealed the tumor as an angiolipoma. Symptoms were relieved after tumor excision, and there were no neurological sequelae. Although extremely rare, lumbar epidural angiolipoma should be considered in the differential diagnosis of lumbar spinal epidural lesions. The prognosis after surgical management of this lesion is favorable.

Keywords: Angiolipoma; Lumbar epidural tumor; Spinal neoplasm.

Fig. 1

A : T1-weighted sagittal magnetic resonance (MR) image showing a hyperintense portion of the mass at the L5 level (suggesting a fatty component) and a low signal portion at the S1 level (indicating vascularity). B : Fat suppressed T1-weighted sagittal MR image with gadolinium shows hyperintensity at the S1 level and low signal intensity at the L5 level. C : T1-weighted axial MR image showing a high intensity mass displacing the S2 root laterally at the left S1 level. D : Fat suppressed T1-weighted axial MR image with gadolinium shows a highly enhanced mass. E : Computer tomography sagittal reconstruction image showing a low density mass at the L5-S1 level.

Fig. 2

A : A yellowish hypervascular mass is observed displacing the nerve root dorsally between the left S1 and S2 nerve roots. B : The S1 and S2 nerve roots are seen following the complete removal of the tumor.

Fig. 3

Histological examination of the tumor revealed a well-vascularized area comprising mature adipocytes and large branching blood-filled cavernous vascular channels, and a hypovascularized area suggestive of a conventional lipoma (×40 magnification; HE stain)