Fig. 1

A, B Contrast-enhanced CT performed when the patient was diagnosed with pancreatic lipoma 12 years previously. A well-defined 6 cm mass composed of homogeneous adipose tissue without any solid nodules in the pancreatic head is visible (arrowheads). C–E Contrast-enhanced CT before surgery. The previously diagnosed 12 cm adipose tumor is visible in the pancreatic head (arrowheads). An irregular isodense mass appeared at the upper margin of the tumor (arrow), which invaded and obstructed the distal common bile duct