RECEIVER OPERATING CHARACTERISTIC (ROC) CURVE ANALYSIS OF THE TUMOR-MARKERS CEA, CA-19-9 AND CA-72-4 IN GASTRIC-CANCER

Pre-surgery serum levels of CA 72-4, CEA and CA 19-9 were quantified b y the enzyme immunoassay method in 167 patients with histological diag nosis of gastric adenocarcinoma and in 92 patients with an endoscopic diagnosis of benign gastric pathology, CA 72-4 showed a better correla tion between its serum levels and the different clinical stages of the disease than CEA and CA 19-9, At the individual study of stages I-II, CA 72-4 proved positive in 36.9% of patients while CEA and CA 19-9 ap peared positive in 10.8 % and 8.6%, respectively, In the ROC curve, at a specificity of 95 %, the sensitivities of CA 72-4, CEA and CA 19-9 were 59.8%, 21% and 26.3% respectively, The discriminatory capacity of the test (area under the ROC curve+/-SD) was 0.86+/-0.03 in the case of CA 72-4, 0.52+/-0.03 for CEA and 0.58+/-0.03 for CA 19-9, In conclu sion, in our series and with regard to CEA and CA 19-9, CA 72-4 shows better sensitivity and discriminatory capacity, CEA and CA 19-9 do not provide significant benefits when combined with CA 72-4 due to the go od results obtained with the later marker alone.