Atypical giant hepatic haemangioma with centrifugal enhancement

Clinical History

A 21-year-old lady presented with a 6 month history of gradually worsening vague pain in the right upper quadrant. On examination, a firm, non-tender hepatomegaly was noted. Systemic examination otherwise was unremarkable. Routine laboratory tests were normal.

Imaging Findings

Sonography revealed a mixed echotexture mass lesion in the left liver lobe. This lesion was subsequently evaluated with CT scan of the abdomen. Unenhanced CT revealed a large (>10 cm) hypoattenuating mass occupying almost the entire left lobe (Fig. 1). No intralesional calcification was seen. On dynamic contrast-enhanced CT, no significant enhancement was noted in the arterial phase except for a few centrally located small enhancing foci (Fig. 2). A more globular central enhancement was appreciated on the venous phase scan (Fig. 3). There was gradual opacification from the centre to the periphery (centrifugal direction) during the delayed phases (Fig. 4, 5). Similar findings were also seen at MRI (Fig. 6). Since the patient was symptomatic the lesion had to be enucleated. Per-operatively the mass was partially exophytic and was predominantly arising from the segments IV and V of the liver.

Discussion

Haemangiomas are composed of large endothelial lined vascular channels filled with slowly moving blood. The channels are supported by collagenous walls. Peripherally located vascular lakes and central fibrosis is supposedly responsible for the characteristic ‘centripetal’ enhancement pattern i.e. an early peripheral-nodular enhancement with subsequent partial or complete fill-in. An atypical centrifugal (inside-out) appearance of contrast enhancement is rare. Limited case reports are available in the medical literature highlighting such an atypical presentation on US, CT or MRI. A variation in the tumour structure has been postulated to be responsible for such an unusual (centrifugal) enhancement pattern. Reports have suggested that an atypical central location of the vascular spaces together with predominantly peripherally placed fibrous component is responsible for the centrifugal pattern of enhancement i.e. an early central and progressive inside-out enhancement of the lesion. In our patient, triple-phase CT scan of the liver demonstrated a large hypoattenuating lesion in the left and right hepatic lobe. It exhibited central enhancing foci in the arterial phase followed by a progressive centrifugal enhancement on the portal-venous and delayed phase scans (Fig. 2-5).

To conclude, a centrifugal (inside-out) enhancement pattern on dynamic contrast-enhanced CT scan is a rare but possible feature of hepatic haemangioma.

Differential Diagnosis List

Final Diagnosis

Atypical giant hepatic haemangioma with centrifugal enhancement

URL:	https://www.eurorad.org/case/9102
DOI:	10.1594/EURORAD/CASE.9102
ISSN:	1563-4086