The Study Of Tumor Markers And Gene Mutations In The Bile For Differential Diagnosis Of Cholangiocarcinoma And Benign Bile Duct Stricture

Cholangiocarcinoma(CCA)affiliated to malignant bile duct stricture. Malignant bile duct stricture is more in bile duct stricture, benign stricture is low.Sometimes the both differential diagnosis is difficult. Although medical imaging techniques of ERGP and PTC et.al is useful for the differential diagnosis of benign and malignant bile duct stricture, the qualitative dignosis is usual difficult.The incidence of CCA is increasing annually with low resectability, worst prognosis and generally affects aged patients in whom the use of bile duct stent become a treatment of choice. Currently, some problems still existing in the diagnosis and treatment of CCA: (1) Imaging techniques lacked standard guidance notions. Sometimes it is difficult to diagnoses qualitatively(2) Differential diagnosis of bile duct benign and malignant lesions did not get enough regards, and bile duct benign lesions were sometimes misdiagnosed and treated as CCA (3 ) Now the sensitivity of cytology for the diagnosis of CCA is still low. The sensitivity of cytological diagnosis of bile duct brushings and bile for CCA is only highest to 40% and 30% or so.In auther's hospital, the sensitivity of cytological diagnosis of bile duct brushings is only 20% or so. Sometimes only detect cytometamorphosis and it is difficult to dignoses qualitatively. The sensitivity of cytological diagnosis of bile forCCA is only 10% or so. (4)Serum tumor markers have a certain supplementry diagnosis value,but the sensitivity and specificity are not high.(5)The placement of bile duct metallic stent without accurate diagnosis could hide serious medical treatment troubles. Therefore, the research of qualitative diagnosis techniques of CCA before treatment must has important clinical value. The current studies include two parts summarized as follow:Part one:The Study of tumor markers in the bile for differential diagnosis of cholangiocarcinoma and benign bile duct strictureObjective: To evaluate the usefulness of determing tumor markers in the bile for diagnosis of Cholangiocarcinoma(CCA) and benign bile duct strictureMethods: When ERCP and PTC,we extracted bile from bile ducts in 37 cases with bile duct carcinoma,35 cases with benign bile duct stricture and 25 cases relatively normal persons who were not hepatopancreatobiliary disease.Radioimmunoassy (RIA) and Immunoradiomassay(IRMA) were used to assay the content of CAi9₉,CAso and CEA in bile and in serum.Results: The cut off (dividing value) of bile CAi9₉ CAso and CEA were llOOu/mL > 30n / mL and 54ng / mL respectively.In bile,the sensitivity for the diagnosis of CCA was 97.29%%for CA19₉> 78.37% for CA50 and 81.08% for CEA;the specificity was 85.72% forCAi9_^ 71.43% forCA50 and 74.29% for CEA.In serum,the sensitivity for the diagnosis of CCA was 56.76% forCAi9₉> 45.95% for CA50 and 51.35% for CEA;the specificity was 62.85% for CAi9_^ 54.29% for CA50 and 57.14% for CEAJn bile,the sensitivity and specificity were better than those in serum (PO.05) .The falespositive rate (FPR) of bile CAi9₉ (14.28% ) was very lower than the FPR of bileCAso (28.57%) and bile CEA (25.71%) (PO.01) .Conclusion: Bile CAi9₉> CA50 and CEA are effective tumor markers in the differential diagnosis of cholangiocarcinoma and benign bile duct stricture. Furthermore,the bile tumor markers are better than serum tumor markers to diagnose the CCA .Bile CAi9₉ is better than bile CAso and bile CEA to dignose CCA.Part two:The Study of gene mutation in the bile for differential dignosis of cholangiocarcinoma and benign bile duct strictureObjective: To explore The clinic usefulness of p53 and K-ras gene mutation in the bile for differential dignosis of cholangiocarcinoma(CCA) and benign bile duct stricture.Methods: We performed PCR-SSCP and DNA sequensing to detect p53 mutation in exons 5 through 8 and K-ras gene exon one mutations in the supernatant and sediment of bile, we extracted bile from bile ducts in 27 cases with CCA,22 cases with benign bile duct stricture.Results: Either p53 or K-ras mutation were detected in 23 of 27 Cholangiocar-cinoma cases. K-ras mumation were detected in 21 of 27 Cholangiocarcinoma cases;p53 mumation were detected in 19 of 27 Cholangiocarcinoma cases.There was no evident different in the both. In bile supernatant from patients with CCA, p53 and K-ras mutations were detected in62.96% (17/27) and 66.67% (18/27) of cases respectively. The incidence of p53 and K-ras mutations in the sediment was 44.44%(12/27) and 59.26%(11/27) respectively.5 cases K-ras mumation were only detected in supernatant and 3 cases K-ras mumation were only detected in sediment of 21 CCA cases in which K-ras mumation were detected. 7 cases p53 mumation were only detected in supernatant and 2 cases p53 mumation were only detected in sediment of 21 CCA cases in which p53 mumation were detected.The incidence of p53 and K-ras mutations is higher in the supernatant than in the sedimentOnly 4 cases were not observed mutation in 27 cases of CCA. When a combination assay with both genes was used, molecular abnormalities were detected in 85.19%(23/27) of cases, including 2 in which p53 alone was positive and 4 in which K-ras alone was positive . No mutation was observed in benign bile duct stricture.There was no relationship of the mutation of p53 and K-ras with the location of the cancer > its histological types or its clinical staging.Conclusion: The sensitivity and specificity for the diagnosis of CCA were quitely high when When a combination assay with both genes(p53 and K-ras) of bile was used.lt has a important practical value for the qualitative diagnosis of CCA.It also has a important clinical value for the differential diagnosis of bile duct carcinoma and benign bile duct stricture.The incidence of p53 and K-ras mutations is higher in the supernatant than in the sediment, and simultaneous analyses of p53 and K-ras in the two bile fractions could enhance the genetic diagnosis of CCA.