Adenosquamous Carcinoma of the Gallbladder: A Case Report

Background/Purpose: Adenosquamous carcinoma of the gallbladder is a relatively rare histological subtype, accounting for approximately 1-5% cases of gallbladder carcinomas. The scarcity of this tumor and its poor prognosis contribute to the clinical challenges associated with its diagnosis and management. Case: We present a case of a 65-year-old female with a past medical history particularly significant for cholelithiasis, choledocholithiasis, and gallstone pancreatitis who presented to the emergency room with complaints of severe right upper quadrant pain of one-day duration. Initial evaluation was remarkable for an abdominal ultrasound with cholelithiasis with a positive sonographic Murphy sign, biliary scan demonstrating persistent non-visualization of the gallbladder, and a mildly elevated Aspartate Aminotransferase (AST) level of 42 U/L (reference 13-40 U/L), while all other liver function tests and liver enzymes were within normal limits. The patient subsequently underwent a cholecystectomy, and the histopathology revealed grade 3, poorly differentiated adenosquamous carcinoma of the gallbladder. Conclusion: The rarity of adenosquamous carcinoma of the gallbladder makes this case particularly noteworthy. Management typically requires a multidisciplinary approach consisting of surgery, chemotherapy, and radiation, however the prognosis remains poor due to the inherent aggressive nature of the disease. Therefore, clinicians should maintain a high level of suspicion in patients with relevant risk factors, including chronic gallstone-related inflammation, primary sclerosing cholangitis, and chronic bacterial infections, so that appropriate evaluation and prompt treatment can be pursued for timely diagnosis and management.