Objective In China, the incidence of extrahepatic bile duct carcinoma (EBDC) tends to increase over the past decades. The etiology of the noted increase in EBDC is not identified. Approximately, in a half of the overa...Objective In China, the incidence of extrahepatic bile duct carcinoma (EBDC) tends to increase over the past decades. The etiology of the noted increase in EBDC is not identified. Approximately, in a half of the overall Chinese patients with EBDC, the causative factors in the development of EBDC have not been demonstrated.There is a high prevalence of hepatitis C virus (HCV) or hepatitis B virus (HBV) in China, both of which can induce malignant transformation of infected cells and strongly associated with hepatocellular carcinoma (HCC). In this study, EBDC tissues from Chinese patients were examined for the presence of HCV and HBV infection to investigate further the potential causes of EBDC.Methods HCV NS5 protein and HBsAg were detected by labeled streptavidin biotin (LSAB) method; HCV RNA and HBV DNA were detected by in situ polymerase chain reaction (IS-PCR) in formalin fixed, paraffin embedded specimens from 51 Chinese patients with EBDC. HCV RNA and HBV DNA were detected by IS-PCR in 34 Chinese patients with specimens of benign lesions of hepatobiliary tract (control group) .Results In 51 case tissue sections of EBDC, NS5 protein was detected in 14 (27.5%), and HBsAg in 5 (9.8%), HCV RNA in 18 (35.4%) and HBV DNA in 8 (15.9%) .respectively, of which HCV and HBV co-infection was detected in 2 (3.9%). In 34 case tissue sections of the control group, HCV RNA was detected in 2 (5.9 % ), and HBV DNA in 3 (8.8%).Conclusion In this study using standard histochemical and PCR techniques, HCV and HBV genomes and their encoding proteins were detected in the tissues of EBDC. The data show that there is a higher than expected incidence of HCV and HBV presence in EBDC tissues than would be expected on serologic grounds. The detectable rate of HCV RNA in EBDC tissues was significantly higher than in control group (x2 = 9.808, P = 0.002). As a result, this study indicates that there is a correlation between the presence of HCV infection and EBDC, and HCV infection has possible etiologic significance in the development of EBDC in China. While HBV DNA was detected in EBDC tissues with the difference in the detectable rate of HBV, DNA being not significance between EBDC tissues and the control group (x2 = 0.853, P = 0.356) . Further research is necessary to determine the presence of a causal relationship between HCV/HBV infection and the development of EBDC.展开更多
文摘Objective In China, the incidence of extrahepatic bile duct carcinoma (EBDC) tends to increase over the past decades. The etiology of the noted increase in EBDC is not identified. Approximately, in a half of the overall Chinese patients with EBDC, the causative factors in the development of EBDC have not been demonstrated.There is a high prevalence of hepatitis C virus (HCV) or hepatitis B virus (HBV) in China, both of which can induce malignant transformation of infected cells and strongly associated with hepatocellular carcinoma (HCC). In this study, EBDC tissues from Chinese patients were examined for the presence of HCV and HBV infection to investigate further the potential causes of EBDC.Methods HCV NS5 protein and HBsAg were detected by labeled streptavidin biotin (LSAB) method; HCV RNA and HBV DNA were detected by in situ polymerase chain reaction (IS-PCR) in formalin fixed, paraffin embedded specimens from 51 Chinese patients with EBDC. HCV RNA and HBV DNA were detected by IS-PCR in 34 Chinese patients with specimens of benign lesions of hepatobiliary tract (control group) .Results In 51 case tissue sections of EBDC, NS5 protein was detected in 14 (27.5%), and HBsAg in 5 (9.8%), HCV RNA in 18 (35.4%) and HBV DNA in 8 (15.9%) .respectively, of which HCV and HBV co-infection was detected in 2 (3.9%). In 34 case tissue sections of the control group, HCV RNA was detected in 2 (5.9 % ), and HBV DNA in 3 (8.8%).Conclusion In this study using standard histochemical and PCR techniques, HCV and HBV genomes and their encoding proteins were detected in the tissues of EBDC. The data show that there is a higher than expected incidence of HCV and HBV presence in EBDC tissues than would be expected on serologic grounds. The detectable rate of HCV RNA in EBDC tissues was significantly higher than in control group (x2 = 9.808, P = 0.002). As a result, this study indicates that there is a correlation between the presence of HCV infection and EBDC, and HCV infection has possible etiologic significance in the development of EBDC in China. While HBV DNA was detected in EBDC tissues with the difference in the detectable rate of HBV, DNA being not significance between EBDC tissues and the control group (x2 = 0.853, P = 0.356) . Further research is necessary to determine the presence of a causal relationship between HCV/HBV infection and the development of EBDC.