TPA and CA 15.3 measurements for breast cancer monitoring in a routine setting

TPA and CA 15.3 concentrations were routinely determined in serum of patients treated for breast cancer during a 15-month period. ROC curves did not show differences in the ability to differentiate between NED and PD on the basis of matching tumor marker values. During monitoring of patients with NED, TPA levels showed fluctuations of more than 25% that were not disease related. We concluded that CA 15.3 is a more slowly reacting marker of tumor burden than TPA, which is an immediate indicator of cell turnover.