中文摘要：

BACKGROUND:Combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CC) is an uncommon subtype of primary hepatic carcinoma,and its prognosis is poor.This study was undertaken to investigate the prognosis and the clinicopathological characteristics of cHCC-CC,including their possible cellular origin.METHODS:Among 852 patients with a primary hepatic carcinoma who underwent hepatectomy from January 1998 to April 2008 at our hospital,cHCC-CC was identified in 14 patients The clinicopathological characteristics of the 14 patients were analyzed retrospectively.The expression of the liver stem cell markers (c-kit,CD90,CD133 and CK19) in the tumor tissue was detected by immunohistochemistry,and the Kaplan-Meier method was used to evaluate survival.RESULTS:Among the 14 patients,9 presented with abdominal pain,3 with anorexia and debilitation,and the remaining two patients were asymptomatic.The mean age was 53.6±3.0 (range 38-74) years.Among the included patients,11 had an elevated serum alpha-fetoprotein level,13 were infected with hepatitis B virus,9 had vascular invasion and 1 had lymph node metastasis The average diameter of the tumors was 9.9±1.1 (range 5.0-16.0) cm.The median overall survival time was 7.9±1.0 months In addition,the presence of the liver stem cell markers,c-kit CD90,CD133 and CK19 was 71.4%,85.7%,92.9% and 78.6% respectively.All four markers were simultaneously expressed in eight cases.CONCLUSIONS:cHCC-CC has aggressive characteristics and the prognosis is extremely dismal.The high expression of liver stem cell markers in the tumor tissue suggests that these tumors may derive from liver stem cells.