S1376 A Case of Benign Gallbladder Disease With Elevated Tumor Markers

Abstract

INTRODUCTION: Xanthogranulomatous cholecystitis (XC) is a rare, uncommon variant of chronic cholecystitis; XC is a benign inflammatory disease of the gallbladder that can be misdiagnosed as gallbladder carcinoma on imaging. This disease is characterized by focal or diffuse destructive inflammatory processes and can implicate significant morbidity as the inflammation usually extends into the gallbladder wall and then into adjacent structures. The hallmark of XC is large collections of lipid-laden macrophages, fibrous tissue, and acute and chronic inflammatory cells. CASE DESCRIPTION/METHODS: Our patient is a 61 year old male with no past medical history who presented to the hospital with 1 week of worsening colicky abdominal pain mainly localized to the right upper quadrant. Labs were remarkable for increased indirect bilirubin and elevated liver enzymes, primarily cholestatic. CT of the abdomen showed a contracted gallbladder (GB) with no significant acute findings. Ultrasound of gallbladder was consistent with cholelithiasis and GB wall thickening with a dilated common bile duct measuring 10mm with intrahepatic biliary dilation. MRCP revealed minimal common bile duct dilatation, questionable impacted stone, and a completely decompressed GB which limited the study’s imaging. Tumor markers were showed both elevated AFP and CA19-9. An ERCP with sphincterotomy subsequently removed multiple choledocholithiasis without resolution of transaminitis. EUS looked for an occult malignancy but was unremarkable. Given the absent findings in the setting of abnormal imaging, the patient proceeded with cholecystectomy with staging laparoscopy to assess for primary or metastatic malignancy. Frozen sections were negative for neoplasm. His final pathology was negative for malignancy but showed fibrous tissue formation and lipid-laden macrophages consistent with XC. DISCUSSION: Xanthogranulomatous cholecysitis continues to be a diagnostic challenge as there is no single modality to identify this disease. The definitive diagnosis is always on final histopathology. It is seen in 1.3% to 5.2% of resected gallbladder specimens. Due to its similarities with gallbladder carcinoma, XC is responsible for approximately 1 in 10 patients being either over treated with unnecessary extended resection or undertreated for a missed GBC. Our case further illustrates how careful identification of clinical symptoms, radiological features, and intraoperative frozen section can avoid unnecessary morbidity associated with radical surgery.Figure 1.: Decompressed gallbladder on MRCP.Figure 2.: Histopathology slide of XGC showing foamy macrophages and dense fibrous tissue.