Ciliated hepatic foregut cyst: four case reports with a review of the literature.

Ciliated hepatic foregut cysts (CHFCs) are rare congenital legions that arise from the embryonic foregut. The cysts are formed during fetal development by evagination from their respective portions of the foregut, and are characterized by a ciliated epithelial lining. Approximately 100 cases of CHFC have been reported, of which only 13 were in children. Although CHFC is typically benign, malignant transformation to squamous cell carcinoma (SCC) has been reported in 3 cases. Survival rate after progression to malignancy is poor, as SCC in this setting is biologically aggressive. We present 4 new cases of CHFC in children between 5 months and 17 years old. Our cases are unusual, as some of the cysts exhibit multilocularity and biliary communication, and 2 of our patients were diagnosed under the age of 1. Additionally, 1 of the cysts was 19.3 cm in diameter, making it the largest reported CHFC to our knowledge. Ciliated hepatic foregut cysts should be included in the differential diagnosis of hepatic lesions.