Paracaval lipoma

Clinical History

We present a case of a 75-year-old man who underwent computed tomography scan for lung squamous cell carcinoma follow-up after chemotherapy. There were no relevant clinical findings and laboratory data were within normal range.

Imaging Findings

Contrast-enhanced computed tomography (CT) revealed a nodular filling defect with fat attenuation in the medial aspect of the intrahepatic portion of the inferior vena cava (IVC) above the caudate lobe (Fig. 1-3). Retrospectively, it was already present in previous CT scans (Fig. 4). No fill defects were present in the pulmonary arteries and the primary lung tumour in the left lung (Fig. 5) was stable compared to the last CT scan performed 3 months before. A secondary cavitated lesion in the right lung (Fig. 5) was also stable and there were no new secondary lesions. An abdominal aortic aneurysm was also documented (Fig. 3).

Discussion

Paracaval lipoma or pseudolipoma is a rare pseudolesion of the IVC and represents a partial volume artefact of pericaval fat above the caudate lobe rather than a true intraluminal lesion [1-3].
Although this artefact is more frequent in patients with chronic liver disease in whom prominent pericaval fat collections commonly develop, it can be seen in up to 0.5% of CT examinations [1, 4]. The angulation and narrowing of the suprahepatic IVC just before it opens into the right atrium makes it prone to partial volume averaging artefacts on CT and Magnetic Resonance (MR) imaging [2].
Pseudolipoma can mimic bland thrombus of the IVC as well as intracaval spread of tumours on axial images and should be carefully recognized to prevent misdiagnosis and unnecessary diagnostic procedures [3]. Reformatted CT images (coronal and sagittal) or coronal MR imaging help to confirm the true nature of this finding [1].

Differential Diagnosis List

Final Diagnosis

Paracaval lipoma or pseudolipoma of the inferior vena cava

URL:	https://eurorad.org/case/13476
DOI:	10.1594/EURORAD/CASE.13476
ISSN:	1563-4086