Tumour associated antigens CA 15.3 and CA 125 in ovarian cancer

CA 125 and CA 15.3 antigens were determined by enzyme immunoassay in 78 patients with ovarian cancer for a total of 540 determinations. The antigens were also investigated in sera from 100 women with other gynaecological diseases, 82 lung cancer patients and in 39 pleural fluids of varying origin. CA 15.3 reference values were evaluated in 91 healthy women (cut-off: 25 U/ml). CA 15.3 sensitivity at diagnosis (60%) and for detecting relapse (44%) was lower than that of CA 125 (90% and 64.7%, respectively). However, CA 15.3 does not increase with aspecific mesothelial cell reaction and thus it is more specific than CA 125. Combined use of the markers during follow-up improves early detection of relapse (at least one of the two was positive in 79% of cases). Therefore both CA 15.3 and CA 125 should be routinely determined for the detection and monitoring of ovarian cancer.