A 15-year-old girl with acute leukemia who had undergone Kasai's operation for congenital biliary atresia (CBA) at the age of 78 days is presented. Several episodes of ascending cholangitis occurred postoperatively but were controlled and jaundice had not been evident since the 70th day after the operation. At the age of 10 years, massive hematemesis from esophageal varices suddenly developed, and led to a esophageal transection, perigastric de-vascularization and splenectomy. At 15 years and 11 months of age, she suffered from high fever, anorexia, general fatigue and slight jaundice. Blood analysis revealed pre-B cell leukemia. Immediately after the diagnosis, she underwent antileukemic treatment, and a complete remission was obtained 1 month after the treatment. The long-term survivors of CBA have many problems mainly due to the hepatic dys-function. However, no case of malignancy has been reported yet, in spite of possibly higher carcinogenetic potential than in the general population, because of high levels of bile acid and abnormal bile acid in the serum which may cause malignancies. Moreover, impairment of the immunological surveillance system for malignancy occurs and possibly results in development of malignant cells in the patients undergoing splenectomy as well as those with hepatic dys-function.
