Fig. 1

Radiological findings. a Computed tomography (CT) scan of the abdomen showing a well-demarcated liver mass consistent with hemangioma in the anterior segment of the right hepatic lobe to segment IV. The tumor pressed a bile duct in the hepatic portal region, causing an intrahepatic bile duct to expand. b A CT scan performed 5 years prior to the study shows a low-density tumor with a diameter of 28 mm in the right lobe. c The size of the tumor was shown to be 13 cm in diameter in magnetic resonance imaging, with a clearly demarcated border and a heterogeneous signal on T2-weighted images. The tumor had a fluid-fluid level at the tumor margins. d A stricture of approximately 2 cm in length in the common bile duct was observed via endoscopic retrograde cholangiography and suspected to be a result of compression from the outside wall. This caused partial expansion of a right lobe bile duct and high expansion of the left lobe bile duct