Pitfall: a pseudo tumor within the left liver lobe presenting with abdominal pain, jaundice and severe weight loss.
A 51 year old male patient with a history of chronic alcohol consumption and recurrent pancreatitis was referred to our hospital with jaundice, epigastric pain, severe diarrhoea and weight loss of 28 kg within the last 12 months. A CT scan of the abdomen 4 months before admission had shown a pancreatitis with free fluid around the corpus and tail of the pancreas as well as dilated intrahepatic bile ducts and a cavernous transformation of the portal vein. Moreover, a tumor (3.5 x 3.0 x 3.6 cm) with irregular contrast enhancement was seen within the left liver lobe. The patient was referred to us for further evaluation and treatment. The initial B-Mode sonogram revealed a bull's eye like well defined lesion (8.1 x 7.5 x 7.0 cm) within the left liver lobe, consistent with a tumour or abscess. Prior to a diagnostic needle biopsy a PTCD was performed in this case presenting with dilated intrahepatic bile ducts and having a history of Billroth II operation. An additional colour coded Duplex Doppler ultrasonography demonstrated a visceral artery aneurysm and prevented us from performing the diagnostic puncture. The aneurysm was assumed to originate from a variant or a branch of the left hepatic artery. Angiography revealed a pseudoaneurysm of the pancreaticoduodenal artery and coil embolization was performed because of the increasing size and the risk of a bleeding complication. Postinterventional colour duplex ultrasound measurement showed no blood flow within the aneurysm. Retrospectively, the pseudoaneurysm must have led to a compression of the common bile duct, since the patient did not develop cholestasis after embolization and removal of the PTCD. Thus, a pseudoaneurysm of the pancreaticoduodenal artery must be included in the differential diagnosis of liver tumours in patients with chronic pancreatitis, despite its unusual localization near the liver. Therefore, we suggest that colour coded ultrasonography should be applied to any unclear, bull's eye like lesion, even though this method alone cannot exactly determine the origin of the pseudoaneurysm. Interventional angiography remains the gold standard for the diagnosis and therapy of visceral artery aneurysm.