What is the incidence of biliary carcinoma in choledochal cysts, when do they develop, and how should it affect management?

The incidence of cancer in choledochal cysts (CCs) in adults was calculated to determine the timing and need for surgery. In 78 publications (1996-2010), 434 of 5780 reported CCs patients had cancer. Cholangiocarcinoma (70.4 %) and gallbladder cancer (23.5 %) were the most common malignancies. Only nine malignancies were reported before age 18 (0.42 %). In contrast, the incidence of malignancy in adults was 11.4 %. The median age for diagnosis of cancer was 42 years, and the incidence increased with each decade.