Squamous cell carcinoma arising in a ciliated hepatic foregut cyst.

Ciliated hepatic foregut cysts are rare congenital lesions derived from the embryologic foregut. They are considered benign, and a review of 64 published cases revealed no instances of malignant transformation. We report a case of squamous cell carcinoma arising in a ciliated hepatic foregut cyst in a 51-year-old man. The tumor was found during a routine cholecystectomy and involved the adjacent mesentery and duodenal wall. There was histologic evidence of perineural and perivascular involvement. Despite an en bloc resection of the tumor and contiguous areas of gross involvement, the patient died 2 months later. Although aspiration of cyst contents is an accepted treatment for asymptomatic lesions, this case suggests that most ciliated hepatic foregut cysts should be excised, especially when radiologic studies yield equivocal results.