Angiofibrolipoma of Posterior Mediastinum with Transforaminal Extension

Abstract

Angiofibrolipoma is a histological variant of lipoma, which commonly occurs in subcutaneous tissues. In the present report we illustrate the case of an angiofibrolipoma of the posterior upper mediastinum in a 75-year-old man presented with progressive chest pain. Xray chest showed a homogeneous opacity vertically oriented along the right lateral aspect of thoracic vertebrae with an obtuse angle to the mediastinum. The upper extremity of the mass extended above the superior clavicle, suggestive of a posterior mediastinal lesion. Thoracic magnetic resonance imaging revealed a posterior mediastinal mass, in keeping with a nonaggressive lesion, with particular endocanalar extension and heterogeneous signal and enhancement patterns that was highly suggestive of a mixed mesenchymal tumor. The tumor was incompletely removed by right postero-lateral thoracotomy with final diagnosis of angiofibrolipoma. To the author's knowledge, such a case of angiofibrolipoma located in the posterior mediastinum has not been previously reported in the literature.

Keywords: Angiofibrolipoma; MRI; Mesenchymal tumors; Posterior mediastinum.

Figure 1.

Posteroanterior X-ray chest (frontal incidence): i) homogeneous opacity without air bronchogram, vertically oriented along the right lateral aspect of thoracic vertebrae with an obtuse angle to the mediastinum suggestive of a mediastinal opacity; ii) the upper extremity of the mass extends above the superior clavicle, therefore, it is probably located within the posterior mediastinum (cervicothoracic sign); iii) no mediastal shift; iv) no spinal or costal abnormalities seen.

Figure 2.

Non-enhanced magnetic resonance imaging T1 and T2-weighted images before and after fat saturation: i) a mass located in the right costovertebral gutter, well-marginated, with heterogeneous low-signal intensity on T1- weighted images and a high-signal intensity on T2-weighted images. ii) Presence of hyperintense areas within the mass on both T1 and T2 WI that became hypointense after fat suppression corresponding to a fatty component. iii) The tumor extends through the spinal canal, filling the anterior epidural space, from right to left T1-T2 intervertebral foramina. iv) The spinal cord is slightly compressed without signal abnormalities. v) Scalloping of the posterior margin of the body and posterior arches of T1 and T2 VT. vi) The tumor is responsible of widening of both foramina and scalloping of posterior vertebral body and arches of T1 and T2 without cortical destruction.

Figure 3.

Axial and sagittal fat-suppressed post contrast magnetic resonance imaging images: i) the mass shows an intense and heterogeneous enhancement; ii) tumoral extension through the spinal canal, filling the anterior epidural space, from right to left T1-2 intervertebral foramina that are enlarged; iii) there is no enhancement abnormalities of spinal cord next to the tumor.

Figure 4.

Pathological image of the tumor (Hematoxylin and Eosin, 10×): i) association of the three characteristic findings of angiofibrolipomas: mature adipocytes, vascular vessels and collagenous tissue; ii) no evidence of mitosis or cellular pleomorphism.