A 79-year-old male was admitted to our hospital with abdominal pain, jaundice and weight loss. No obvious abnormality was found in the physical examination of the patient. Laboratory results: carbohydrate antigen 19-9 (CA19-9)>400 U/ml(normal range <37 U/ml), total bilirubin (TBIL) 267.1 mumol/L (normal range <23 mumol/L). Other laboratory test results were within the normal range. Because the patient had severe jaundice, he first underwent percutaneous transhepatic cholangio drainage. One month later, he was hospitalized again. Laboratory results: CA19-9 125.2 U/ml, TBIL 96.3 mumol/L. Contrast-enhanced computed tomography (CT) showed that the common bile duct was thickened ( Figure 1A ) and the head of the pancreas was enlarged ( Figure 1B ), but no abnormal enhancing shadow was found. Magnetic resonance imaging (MRI) showed dilatation of the extrahepatic bile ducts ( Figure 1C ) and thickening of the gallbladder wall. The pancreatic head was enlarged : the maximum transverse diameter was about 3.7 cm, the pancreatic signal was uniform, and no exact abnormal enhancement shadow was found ( Figure 1D ). On contrast-enhanced ultrasound, an uneven low-intensity lesion with a size of about 2.8 x 2.7 cm was found in the pancreatic head, with an irregular shape and an unclear boundary. We planned to make a further diagnosis with endoscopic ultrasound fine-needle aspiration, but the patient refused. Based on the above findings, the possibility of a pancreatic head malignant tumor was very high. Therefore, a pancreaticoduodenectomy was planned to be performed. During surgery, dilated and completely obstructed common bile ducts were found, and dense adhesions were present around the portal veins, which could not be divided. It was surmised that the mass invaded the portal vein. To relieve the obstruction, a choledochojejunostomy was performed, and some masses were removed for biopsy.
Numerous foam cell, lymphocyte, and plasma cell infiltrates were found in the resected mass and gallbladder ( Figures 2A-C ). Immunohistochemical findings showed CD68 (+) ( Figure 2D ), CK (-), VIM (+), CD19 (-), Ki-67 (<1%), ALK1 (-), and p53 (-). Immunohistochemical results supported the diagnosis of xanthogranuloma invading the pancreatic head, common bile duct, and gallbladder. After 10 months of close follow-up ( Figures 1E, F ), the patient had no symptoms and a good quality of life.