Giant biliary mucinous cystadenoma mimicking mesenchymal hamartoma of the liver in a child: A case report

Abstract

Introduction: Biliary cystadenomas (BCAs) are rare benign tumors with malignant potential. They are most commonly found in middle-aged women and are quite infrequently reported in children. Even with advanced imaging, diagnosing and distinguishing BCA from other cystic liver lesions remain challenging.

Case presentation: A 5-year-old boy was brought in by his parents to our hospital with abdominal swelling that had been persistent for a year, along with loss of appetite and weight loss. On examination, the abdomen was distended and dull on percussion. We considered mesenchymal hamartoma of the liver (MHL) as the top differential after an abdominal CT scan with contrast showed a multi-loculated cystic tumour. For both definitive diagnosis and therapy, the patient underwent exploratory laparotomy with excision of the cystic mass. Surprisingly, histopathology examination of the resected specimen revealed biliary mucinous cystadenoma (BCA).

Conclusion: Since conservative methods are associated with high recurrence rates, biliary mucinous cystic neoplasms require a high index of suspicion and should be handled with total surgical resection. In the post-operative phase, periodic surveillance imaging is recommended due to the risk of recurrence and malignant transformation.

Keywords: Biliary mucinous cystadenoma; Case report; Ethiopia; Liver cysts; Mesenchymal Hamartoma; Pediatrics.

Fig. 1

Contrast enhanced abdominopelvic CT; axial (A), coronal (B), and sagittal (C) scan demonstrate huge multiloculated cystic mass with enhancing thick wall and septations.

Fig. 2

Intraoperative view; cystic mass which arises from the left lobe of the liver (arrow) before excision (A); enoculated specimen of a huge cystic hepatic mass (B).

Fig. 3

Mucinous cystadenoma of the liver, gross (A) Cystic specimen with smooth glistening surface; Cut surface (B) revealing multilocular cavity filled with seromucinous and turbid fluid.

Fig. 4

Microscopy (A) Low power shows cyst wall fragment with an adjacent normal appearing hepatic parenchyma (arrow); (B) Cyst lining composed of a single layer of mucinous epithelium appearing (C) cuboidal to low columnar with apical mucin on High power field.