AN ASSESSMENT OF THE CLINICAL USEFULNESS OF 2 SERUM MARKERS, CA 15 3 AND HMFG 2 IN LOCALIZED AND METASTATIC BREAST-CANCER

CA 15 3 is a circulating glycoprotein defined by two monoclonal antibo dies (115 D 8 and DF 3) with good specificity for breast cancer. Tumou r-associated antigens have been detected by the monoclonal antibody HM FG 2 using a low pH ELISA method. We compare the values obtained using these two assays in patients with localized and metastatic breast can cer. CA 15 3 and HMFG 2 levels were measured in 61 patients, 24 locali zed and 37 metastatic, evaluated by standard biochemical and radiologi cal testing. Of the patients with metastatic disease 78.4 per cent had an elevated CA 15 3 level whereas only 8.3 per cent of patients with localized disease had an elevated level (chi2 = 28.2 p = 0.001); 29.8 per cent of patients with metastatic discase had elevated HMFG 2 level s while among those with localized disease 16.7 per cent had elevated levels (chi2 = 0.57 p = NS). We conclude that only CA 15 3 is a useful marker in advanced disease.