Background : Xanthogranulomatous inflammation of gallbladder wall can extend and infiltrate adjacent organs which can be mistaken for malignancy on preoperative investigations and, intraoperatively, often leads to extensive surgical resections. Only the histopathologic examination of the specimen allows correct diagnosis.

Methods : We hereby review clinicopathologic findings of a case which underwent extensive surgeries on clinical, radiological and intraoperative suspicion of gallbladder carcinoma which turned out to be xanthogranulomatous cholecystitis. Xanthogranulomatous inflammation extended into liver, duodenum and colon in our case.

Results : A 74-year-old woman was admitted to our hospital for right upper quadrant and epigastrium discomfort and diagnosed as gallbladder carcinoma by ultrasonography, computed tomography and fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) Serum CA19-9 (62.6 U/ml) were elevated. We diagnosed the lesion preoperatively as a gallbladder carcinoma with direct invasion to the liver bed and colon. We performed subsegmentectomy of the liver S4a + S5 and lymph node dissection of the hepatoduodenal ligament with segmental colon resection.

Conclusions : Several reports have demonstrated that FDG-PET is useful in differentiating between benign and malignant lesions in the gallbladder. However, there is a limitation in the ability of FDG-PET to differentiate between inflammatory and malignant lesions. We herein present a case of xanthogranulomatous cholecystitis misdiagnosed as gallbladder carcinoma by ultrasonography and computed tomography. FDG-PET also showed increased activity. In this case, FDG-PET findings resulted in a false-positive for the diagnosis of gallbladder carcinoma.