Primary Gallbladder Carcinosarcoma: A Rare Biliary Malignancy

Abstract

Gallbladder cancer comprises approximately 85-90% of all biliary tract malignancies, with carcinosarcomas accounting for less than 1%. Karl Landsteiner first described sarcomatoid carcinoma in the gallbladder in 1907, with less than 100 cases reported since that time. A 49-year-old male presented with 1 month of sharp, epigastric pain. Initial labs revealed a lipase of 3785 U/l, AST 658, ALT 489, total bilirubin 2.4 mg/dl, and direct bilirubin 1.3 mg/dl. Computer tomography (CT) of abdomen and pelvis revealed intra and extra-hepatic biliary duct dilation, cholelithiasis with biliary sludge, and hyper-enhancement of the gallbladder wall. Magnetic resonance cholangiopancreatography (MRCP) revealed gallbladder wall thickening with a polyp or a large amount of gallbladder sludge. There was no definite evidence of choledocholithiasis. Patient underwent laparoscopic cholecystectomy. Pathology of the gallbladder showed a circumferential tumor at the gallbladder fundus measuring 3.2 cm with gross and microscopic invasion through the muscular wall (Figure 1). The tumor showed glandular differentiation with pleomorphic spindle cell components consistent with sarcomatoid carcinoma of the gallbladder (Figure 2). Tumor markers including AFP, Ca 19-9, and CEA were negative. He underwent further robotic-assisted liver resection with lymphadenectomy. Lymph nodes were negative for malignancy. He was evaluated by oncology and recommended adjuvant platinum based chemotherapy for six months.1243_A.tif Figure 1: Gross image of gallbladder showing a 3.2 cm, circumferential, intramural mass with associated mucosal ulceration1243_B.tif Figure 2: No Caption available.Carcinosarcoma is a rare gallbladder malignancy without clear diagnostic and treatment guidelines. Preoperative diagnosis is difficult as there are no specific radiographic findings. Histologically these tumors are characterized by malignant epithelial and mesenchymal cells, that stain positive for cytokeratin and vimentin respectively. Tumor markers are often nonspecific. Major prognostic factors may include tumor size, staging, and depth of invasion. Primary therapy is surgical resection. Some cases have reported chemotherapy regimens including a combination of 5-fluorouracil with a carboplatin. Overall prognosis is poor in locally advanced disease with a 5-year survival rate of approximately 16%. This case illustrates the importance of considering carcinosarcoma as a differential in a patient with prolonged epigastric pain with non-specific image findings. It stresses the importance of ongoing research to help define adjuvant chemotherapy or chemoradiation regimens to improve survival.