The purpose of this study was to determine the utility of triple-phase helical computed tomography (CT) for differentiating canine hepatic masses. Seventy dogs with hepatic masses underwent triple-phase CT followed by surgical removal of the hepatic masses. Triple-phase helical CT scans for each dog included precontrast, arterial phase, portal venous phase, and delayed phase studies. The removed hepatic masses were histopathologically classified as hepatocellular carcinoma (n = 47), nodular hyperplasia (n = 14), and hepatic metastatic tumors (n = 9) in dogs. Of the 47 hepatocellular carcinomas, the most common CT findings included a heterogeneous pattern with hyper-, iso-, and hypoenhancement in both the arterial and portal venous phases (40/47, 85.1%). Of the 14 nodular hyperplasias, the most common CT findings were a homogeneous pattern with hyper- and isoenhancement in both the portal venous and delayed phases (13/14, 92.9%). Of nine hepatic metastatic tumors, the most common CT findings included a homogeneous hypoenhancement pattern in both the arterial and portal venous phases (8/9, 88.9%). In addition, 5 (55.6%) showed homogeneous hypoenhancement patterns in the delayed phase. Findings from our study indicated that triple-phase CT is a useful tool for preoperative differentiation of hepatocellular carcinoma, nodular hyperplasia, and hepatic metastatic tumors in dogs.

The differential diagnosis of canine adrenal tumors was feasible based on triple-phase CT findings, including morphological features, CT values, and intratumoral contrast attenuation. Preoperative diagnosis using triple-phase helical CT may be useful for surgical planning in dogs with adrenal tumors.

Near-infrared fluorescence imaging may be feasible for intraoperative mapping of hepatocellular carcinomas in hepatic lobes and may help increase the chance of complete resection of hepatocellular carcinoma in dogs.

The purpose of this study was to evaluate the gene expression of growth factors and growth factor receptors of primary hepatic masses, including hepatocellular carcinoma (HCC) and nodular hyperplasia (NH), in dogs. Quantitative real-time reverse transcriptase-polymerase chain reaction was performed to measure the expression of 18 genes in 18 HCCs, 10 NHs, 11 surrounding non-cancerous liver tissues and 4 healthy control liver tissues. Platelet-derived growth factor-B (PDGF-B), transforming growth factor-α, epidermal growth factor receptor, epidermal growth factor and hepatocyte growth factor were found to be differentially expressed in HCC compared with NH and the surrounding non-cancerous and healthy control liver tissues. PDGF-B is suggested to have the potential to become a valuable ancillary target for the treatment of canine HCC.

ABSTRACT. A 13-year-old neutered female Shih Tzu was referred for investigation of a cranial abdominal mass. Investigations including conventional radiography, abdominal ultrasonography and computed tomography confirmed the mass in the caudate lobe of the liver. As a collateral vein originating from the caudal vena cava (CVC) communicated with the azygos vein, the CVC was ligated and transected cranial to the right renal vein and cranial to the mass under temporary occlusion of the thoracic descending aorta and posthepatic CVC. The mass combined with the CVC was excised. The mass was confirmed as hepatocellular carcinoma (HCC). This report describes the first case with successful en bloc resection of a large HCC involving the CVC in a dog. Hepatocellular carcinoma (HCC) is the most common primary hepatic tumor in dogs [4,11,15]. Canine HCC is classified into three morphologic types, massive, nodular and diffuse, and the most common pattern is a massive lesion that involves a single liver lobe [11]. Therefore, liver lobectomy is the recommended treatment, and the prognosis after surgical resection is good in dogs [7,8]. However, in cases of large or right-divisional hepatic tumors involving the CVC, surgical resection has a risk of large hemorrhage. Partial resection or reconstruction of the CVC may be require when the vessel wall is invaded.A 13-year-old neutered female Shih Tzu (weight 6.6 kg) was referred to the Animal Medical Center of Nihon University for investigation of a cranial abdominal mass. In a physical examination, an enlarged abdomen was observed. Complete blood cell count revealed mild leukocytosis (18,300/ml); other hematological and coagulation parameters were within the normal range. The serum biochemical profile was normal, except for increases in the concentrations of serum alanine aminotransferase (684 U/l), alkaline phosphatase (559 U/l) and aspartate aminotransferase (732 U/l). Radiography revealed a large mass in the caudal side of the liver, displacement of the stomach and intestine (Fig. 1A. B) and a small mass in the left caudal lobe of the lung. In an abdominal ultrasound, a large mixed echogenic mass in the right-divisional hepatic lobe and several splenic nodules were confirmed.Computed tomography (CT) showed a large mass in the caudate lobe occupying the abdominal cavity and displacing the right kidney to the caudal side and the portal vein to the left. In CT angiography, a little contrast medium was detected in the CVC, as blood flow through the CVC was interrupted by the mass (Fig. 2). A collateral vein originating from the CVC caudal to the right renal vein communicated with the azygos vein through a lumber vein (Fig. 3A, B). Further, a single congenital extrahepatic portacaval shunt via the left gastric and phrenic veins was confirmed.The hepatic mass was surgically resected 24 days after the initial presentation. After 0.04 mg/kg atropine (Atropine sulfate; Mitsubishi Tanabe Pharma Corporation.) was administered subcutaneously, general anesthesia was induced with intravenous...