Clinical value of serum tumour markers TPA, TPS, TAG 12, CA 15-3 and MCA in breast cancer diagnosis; results from a prospective study.

The aim of this study was to assess the clinical value of five serum tumour markers, TPA, TPS, TAG 12, CA 15-3 and MCA, in the diagnosis of breast cancer. The serum values were measured in a prospective series of patients with breast cancer (n = 82) and benign breast disease (n = 25). The cut-off levels (90% specificity) determined for each test were 109.0 U/1 for TPA, 156.0 U/1 for TPS, 52.5 kU/1 cut-off level for TAG 12 and 24.9 kU/1 cut-off level for CA 15-3, and at the 12.0 kU/1 cut-off level for MCA. Using these cut-off levels the diagnostic sensitivity of the TPA test was 0.23, for the TPS test 0.15, 0.44 for the TAG 12 test, 0.13 for the CA 15-3 test and 0.10 for the MCA test in detecting breast cancer. When the cut-off levels were determined at 95th percentile level for each test, the cut-off level for TPA was 143.0 U/1, 279.0 U/1 cut-off level for TPS, 105.0 kU/1 cut-off level for TAG 12 and 36.7 kU/1 cut-off level for CA 15.3, and at the 15.3 kU/1 cut-off level for MCA. Using these cut-off levels the diagnostic sensitivity of the TPA test was 0.12, 0.01 for the TPS test, 0.06 for the TAG 12 test, 0.06 for the CA 15-3 test and 0.06 for the MCA test in detecting breast cancer. The correlation coefficients in breast cancer patients between TPA and TPS measurements was 0.82, between TPA and TAG 12 measurements it was 0.09, between TPA and CA 15-3 measurements it was 0.08, and 0.11 between TPA and MCA measurements. None of the serum markers studied were significant predictors in breast cancer diagnosis in a logistic regression analysis or in the discriminant analysis. Thus it seems that TPA, TPS, TAG 12, CA 15-3 and MCA have only limited value in breast cancer diagnosis, but their role in the follow-up and prediction of prognosis of breast cancer patients is a subject for further investigation.