A 40-year-old woman presents with a long history of vague upper abdominal pain and frequent indigestion. Physical examination reveals an obese woman with jaundice and abdominal tenderness. Serum bilirubin is elevated (4.2 mg/dL). There is a mild increase in serum AST and ALT (62 and 57 U/L, respectively) and a moderate increase in alkaline phosphatase (325 U/L). Markers for viral hepatitis are negative. Abdominal ultrasound examination shows echogenic stone-like material within the gallbladder and thickening of the gallbladder wall. An intrahepatic mass is also visualized adjacent to the gallbladder. A cholecystectomy is performed. Histologic examination shows dense fibrosis and glandular structures in the wall of the gallbladder. What is the most likely diagnosis?

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