A portal vein cavernoma mimicking a pancreatic mass

A case of intrahepatic mass-forming portal biliopathy mimicking intrahepatic cholangiocarcinoma

A 75-year-old man was referred to our department because of an enlarging intrahepatic mass detected on magnetic resonance imaging (MRI) follow-up for another disease. MRI showed hypointensity on T1-weighted imaging and hyperintensity on T2-weighted imaging in liver segment 4. Abdominal plain computed tomography (CT) indicated a low-density lesion with an unclear boundary, measuring approximately 4 cm × 3 cm in liver segment 4. Dynamic CT showed early rim enhancement and gradual central enhancement. Contrast-enhanced CT also showed occlusion of the portal vein in segment 4. As the possibility of intrahepatic cholangiocarcinoma could not be excluded on imaging studies, we performed laparoscopic left medial sectionectomy. Histologically, the lesion showed diminished numbers of hepatocytes with increased collagen fibers compared with normal, with no patent portal vein. We considered this lesion a reactive lesion caused by collapse of the liver parenchyma owing to localized obstruction and loss of the portal vein. This lesion was pathologically diagnosed as portal biliopathy. We experienced an extremely rare case of intrahepatic mass-forming portal biliopathy that mimicked a hepatic tumor, which was diagnosed by laparoscopic resection. Portal biliopathy rarely forms intrahepatic mass lesions and must be distinguished from a malignant hepatic tumor.

CT features of non-malignant portal vein thrombosis: a pictorial review

Portal vein thrombosis (PVT) is a rare clinical entity in general population, but a relatively frequent entity in liver cirrhosis. Severe PVT-related complications are potentially lethal, such as ischemic intestinal infarction and complications of portal hypertension. Additionally, occlusive PVT can not only increase the incidence of variceal rebleeding, but also significantly decrease the cirrhotic patients' survival. Based on the clinical significance of PVT, early diagnosis is very critical to allow for rapid establishment of appropriate treatment and improvement of prognosis. Dynamic CT scan is an important diagnostic modality of PVT. The objective of this pictorial review is to illustrate various CT features of non-malignant portal vein thrombosis and its associated abnormalities. Evolution of portal vein thrombosis, such as stage, degree, and extension of thrombus, can be evaluated according to CT demonstrations, which is helpful to timely adopt appropriate treatment modality. Other associated CT findings include the dilation of collateral veins around the obstructed portion of portal vein and the hepatic perfusion and morphology abnormalities.

Pancreatic portal cavernoma in patients with cavernous transformation of the portal vein: MR findings

The purpose of the article was to prospectively evaluate the MR findings of pancreatic portal cavernoma in a consecutive series of patients with cavernous transformation of the portal vein. This study was approved by the review board of our institution, and informed consent was obtained. The clinical and biological data and the MR imaging for 20 patients (11 female, 9 male; median age, 49 years) with cavernous transformation of the portal vein and no evidence of previous pancreatic disease were reviewed. The presence of pancreatic portal cavernoma (defined as intra- and/or peripancreatic portal cavernoma), morphological changes in the pancreas, biliary and ductal pancreatic abnormalities, and extension of the portal venous thrombosis were qualitatively assessed. Fifteen patients (75%) had pancreatic portal cavernoma with collateral formation in the pancreas and/or collaterals around the pancreas seen on dynamic contrast-enhanced MR sequences: three patients had both intra- and peripancreatic portal cavernoma, six had intrapancreatic portal cavernoma alone and six had peripancreatic portal cavernoma only. The presence of intra- or peripancreatic portal cavernoma was significantly associated with extension of the thrombosis to the splenic and superior mesenteric veins (p = 0.05). Morphological changes in the pancreas, heterogeneity on T2-weighted sequences and main ductal pancreatic abnormalities were seen in two, four and two patients, respectively. All these patients had intrapancreatic portal cavernoma. Bile duct dilatation was observed in 13 (65%) patients: among them three had extrahepatic dilatation only and these three patients had associated intrapancreatic portal cavernoma. In patients with cavernous transformation of the portal vein, intra- or peripancreatic portal cavernoma is common. In conclusion, intra- or peripancreatic portal cavernoma was only observed in patients with extension of the thrombosis to the splenic vein and/or the superior mesenteric vein.

Pancreatic and peripancreatic diseases mimicking primary pancreatic neoplasia

A variety of anatomic variants and pathologic conditions in and around the pancreas may simulate primary pancreatic neoplasia at routine abdominal cross-sectional imaging. An ambiguous lesion whose appearance suggests a pancreatic origin requires a broad differential diagnosis that can subsequently be narrowed on the basis of both clinical history and features at optimal computed tomography (CT) and magnetic resonance (MR) imaging. Pancreas-specific multidetector CT and MR imaging techniques with thin collimation, multiplanar and multiphasic scans, and newly introduced curved planar reformation may help avoid potential diagnostic pitfalls. These techniques can help identify and characterize a mass in multiple viewing planes, thereby helping distinguish a true pancreatic neoplasm from peripancreatic adenopathy or from a tumor of the adjacent duodenum or small bowel. They can also help determine the cause of a tumor. It is important that the radiologist be familiar with the wide spectrum of anatomic variants and disease entities that can mimic primary pancreatic neoplasia in order to initiate the appropriate lesion-specific work-up and treatment and avoid unnecessary tests or procedures, including surgery.