Triple-phase helical computed tomography of an arterio-hepatic venous shunt in a hepatic tumor in a dog

Abstract

A 10-year-old French bulldog presented with an abdominal tumor. Triple-phase helical computed tomography was performed, revealing a hepatic tumor, an enlarged hepatic lymph node, and no masses in other organs. The hepatic tumor demonstrated marked enhancement, similar to that of the aorta in the arterial phase. The tumor had rich vascularization and a hepatic arterio-venous shunt formed between the hepatic artery and middle hepatic vein. The hepatic tumor was surgically removed and histological diagnosis revealed a hepatic carcinoid tumor. During surgery, rapid massive arterial hemorrhage occurred from the site of the incision. The animal died without improvement post-surgery. In the case of an arterio-venous shunt in a hepatic tumor, it is important to be careful to avoid perioperative bleeding.

Keywords: abdomen; arterio-venous shunt; canine; computed tomography; liver tumor.

Fig. 1.

A contrast computed tomography image demonstrating the heterogeneous pattern evident in all phases. A hepatic tumor (black arrow) was located in the quadrate lobe and right medial lobe. (A) Precontrast computed tomography image. (B) Arterial phase. The tumor showed marked enhancement. The middle hepatic vein, which was connected to the tumor, and the caudal vena cava were enhanced, but the left hepatic vein was not enhanced. (C) Portal phase. (D) Delay phase. The tumor showed washout in the portal venous and delay phases. The left hepatic vein was enhanced from the portal vein. MHV: Middle hepatic vein, LHV: Left hepatic vein.

Fig. 2.

Multiplanar reconstruction image (A) and 3D image (B) in arterial phase. The tumor was directly connected to the hepatic artery. There was a hypervascular formation in the tumor; the hepatic artery, medial hepatic artery, and middle hepatic vein were connected in tumor. Black arrow and purple region: Hepatic tumor. White arrow: Barium sulfate in colon. AO: Aorta, CVC: Caudal vena cava, HA: Hepatic artery, H LYM: Hepatic lymph node.

Fig. 3.

Contrast computed tomography image demonstrating enlarged hepatic lymph nodes. The right hepatic lymph node showed a heterogeneous pattern (the marginal region was markedly enhanced and the center region was poorly enhanced), while the left hepatic lymph node showed homogeneous enhancement. The portal vein showed exclusion by two enlarged hepatic lymph nodes. Black arrow: Hepatic tumor. White arrow: Barium sulfate in colon. H LYM: Hepatic lymph node, PV: Portal vein.

Fig. 4.

Histological findings of the mass. The mass was composed of nests and packets of polyhedral cells (A). The neoplastic cells had moderate amounts of eosinophilic, granular cytoplasm and round vesicular nuclei (B). A ×40, B ×200: Hematoxylin and eosin stain.