Silent Giant: Surgical Resection of a Large Biliary Cystadenoma in a 47-Year-Old Male With Underlying Steatohepatitis.

Biliary cystadenomas are benign cystic neoplasms of the liver with recognized malignant potential. They are frequently asymptomatic and are often discovered incidentally during imaging for unrelated complaints. Early identification and complete surgical excision are recommended to prevent malignant transformation. We report the case of a 47-year-old male who was incidentally found to have a large, complex hepatic cyst during evaluation for mild, non-specific abdominal discomfort. Cross-sectional imaging revealed an 8 × 9.4 × 9 cm multiloculated cystic lesion involving hepatic segments VII and VIII, without radiological features suggestive of malignancy. The patient underwent elective open anatomical resection of segments VII and VIII. Histopathological examination confirmed a benign biliary-type cystadenoma, with background liver parenchyma showing severe steatohepatitis involving more than 60% of hepatocytes. The postoperative course was uneventful. This case highlights the importance of definitive surgical management of large biliary cystadenomas, even in asymptomatic patients, and underscores the added clinical considerations when significant hepatic steatosis is present.