Abstract
Tissue polypeptide specific antigen (TPS) measures an antigenic determinant associated with human cytokeratin 18. TPS is a marker of tumor cell activity in contrast to markers related to tumor burden. The value of detecting circulating TPS lies in the early detection of recurrence by serial determinations and in the rapid assessment of the efficacy of the treatment. Pretreatment levels of TPS in patients with metastatic breast cancer are related with prognosis. Decreasing TPS levels during therapy monitoring indicate response and a fast response is correlated to favourable prognosis. Increasing TPS levels, in the presence of clinically stable disease or partial remission, predict disease progression with a considerable lead-time. Improved effectiveness in breast cancer management can be seen when TPS is used in combination with CA 15-3. When tumor marker determinations are applied in a proper way in the appropriate situation, the results can assist the oncologist. Thus monitoring of therapy in patients with metastatic breast cancer should be based upon serial TPS and CA 15-3 determinations in serum. The use of tumor marker determinations in the early follow-up interval following surgery to detect early tumor recurrence may be simpler, more sensitive and less expensive than imaging methods.