TISSUE POLYPEPTIDE ANTIGEN AND TISSUE POLYPEPTIDE SPECIFIC ANTIGEN INPRIMARY BREAST-CANCER - EVALUATION IN SERUM AND TUMOR-TISSUE

Tissue polypeptide antigen, measured by both a polyclonal antibody (TP A IRMA Prolifigen (R)) and a monoclonal antibody prototype kit (TPA-M IRMA Prolifigen (R)), and the tissue polypeptide specific antigen were evaluated. The markers were measured in 266 serum samples and in 291 tumour cytosols from patients with primary breast cancer. The three ma rkers were available in matched pairs of both serum and cytosol from t he same patient in 144 cases. Diagnostic sensitivity of serum levels o f the three markers was not significantly different when using cut-off values calculated on the basis of healthy subjects. In the cytosol, t issue polypeptide antigen (TPA IRMA), tissue polypeptide antigen (TPA- M IRMA) and tissue polypeptide specific antigen were significantly cor related with steroid receptor status, while their serum levels were no t. Cytosol and serum levels of the three markers were not significantl y associated. All three were significantly correlated both in serum an d in cytosol. The association was closer between tissue polypeptide an tigen (TPA IRMA) and tissue polypeptide antigen (TPA-EA IRMA) than bet ween each of these two markers and tissue polypeptide specific antigen . From these findings we draw the following conclusions: 1. Tissue pol ypeptide specific antigen (TPA IRMA) and tissue polypeptide antigen (T PA-M IRMA) probably provide superimposable information both in serum a nd in cytosol; 2. Tissue polypeptide specific antigen and tissue polyp eptide antigen (TPA IRMA) or tissue polypeptide antigen (TPA-M IRMA), although closely associated, probably measure in part different cytoke ratins. Therefore, they should not be considered interchangeable in in dividual patients; 3. The determination of the markers in serum and in cytosol provides different information concerning the tumour phenotyp e.