The Study On Combined Detection Of P53 Protein And Tumor Markers In Serum For Patients With Digestive Cancer

Background Recently, about 15 million patients die for malignant neoplasms one year in China, above 60% of them are patients with digestive malignant neoplasms. even treated by the radical surgery,still has some patients died for local recurrence and distant metastasis. Early detection of distant metastasis is an effective mean to improve prognosis. p53 gene mutations and subsequent mutant type P53 protein expression can make the metastatic potential of tumor cells increase. At present, Receiver Operator Characteristic curve analysis is widely recognized as best method for the measurement of diagnostic information and diagnostic decision quality.Objective we carried out this study and aimed to investigate the clinical significance of combined detection of P53 protein and tumor markers carcinoembryonic antigen,carbohydrate antigen 19-9,carbohydrate antigen 242,cancer antigen 72-4 in serum on auxiliaryly determining the distant metastasis of digestive malignant neoplasm.Method There were 55 post-operation patients with digestive malignant neoplasms ,which contains 3cases of esophageal carcinoma,20 cases of gastric cancer,24cases of colorectal cancer,4cases of liver cancer,1 cases of pancreatic carcinoma and 3 cases of carcinoma of gallbladder, diagnosed by pathology, all the cases were divided into metastasis group (19 cases with distant metastasis) and non-metastasis group (36 cases without distant metastasis) by imageology and physical examination, in addition to 14 healthy volunteers. We detected the level of P53 protein and CEA,CA19-9,CA242,CA72-4 in serum by enzyme-linked immunosorbent assay (ELISA). All the markers were evaluated by Receiver Operator Characteristic curve, fourfold table method. And some indicators were given necessary and reasonable combined detection. Results The P53 level in serum in metastasis group were higher than that in non-metastasis group(P<0.05), which in metastasis group and non-metastasis group were both higher than that in healthy control group(P<0.05),and the level of CEA,CA72-4,CA19-9,CA242 in metastasis group were higher than that in non-metastasis group(P<0.05).The areas under ROC curve of them for diagnosing the distant metastasis of digestive malignant neoplasm were respectively0.927(P53),0.864(CEA),0.836(CA72-4),0.806(CA19-9),0.797(CA242).the optimal cut-off values were respectively 0.4086U/ml(P53),3.21μg/L(CEA),3.22U/ml(CA72-4 ),27.28U/ml(CA19-9),16.48U/m(lCA242). When they were detected separately for determining the distant metastasis of digestive malignant neoplasm, the sensitivities were respectively 84.2% (P53),89.5% (CEA),73.7% (CA72-4),73.7%(CA19-9),68.4%(CA242),the specificities were respectively 100.0% (P53),86.1% (CEA),91.7% (CA72-4),83.3(CA19-9),88.9%(CA242),the positive likelihood ratio of P53 was +∞. For parallel test of P53 and CEA, the sensitivity was 100.0%, the specificity was 86.1%, and the likelihood negative likelihood ratio was 0.0.Conclusion P53 was a valuable single marker for determining the distant metastasis of digestive malignant neoplasm. When P53 protein in serum≥0.4086U/ml, it could be used to assistant diagnose the distant metastasis of digestive malignant neoplasm. When P53 and CEA were both negative, namelyP53<0.4086U/ml and CEA<3.21μg/L, it could be used to auxiliaryly deny the distant metastasis of digestive malignant neoplasm.