Malignant change in the biliary tract after excision of choledochal cyst

Background Choledochal cyst is a rare congenital condition with a high risk of malignant change if untreated. The risk of malignancy after surgical excision of choledochal cyst is not known. Methods Forty-eight patients with choledochal cysts managed over a 21-year period were reviewed, to determine the risk of malignant change after cyst excision. Thirty-nine of 48 patients had no carcinoma at first admission; their mean(s.d.) age was 20(18) years. Thirty-seven of 39 patients underwent cyst excision and cholecystectomy followed by hepaticoenterostomy. Results Cyst excision was incomplete in 28 of the 37 patients because dilated portions of the biliary ducts remained proximally and/or distally. In these 37 patients, no carcinoma has developed in the remnant proximal hepatic duct or the terminal bile duct after mean(s.d.) follow-up of 9·1(6·4) years. In the remaining nine patients, biliary carcinoma was diagnosed at the first visit. Six patients died from recurrence with a mean(s.d.) survival time of 13(11) months, while three patients were alive and free from recurrence 2 months, 1 year and 7 years after operation. Conclusion Malignant change has not been observed after total or subtotal excision of choledochal cysts in this series.