TPS (TM): A cytokeratin serum tumor marker for effective therapy control of cancer patients with focus on breast cancer

Tissue polypeptide specific antigen (TPS) measures an antigenic determinant associated with human cytokeratin 18, TPS is a marker of tumor cell activi ty in contrast to markers related to tumor burden. The value of detecting c irculating TPS lies in the early detection of recurrence by serial determin ations and in the rapid assessment of the efficacy of the treatment. Pretre atment levels of TPS in patients with metastatic breast cancer are related to prognosis. Decreasing TPS levels during therapy indicate response and a fast response is correlated to favorable prognosis, Increasing TPS levels, in the presence of clinically stable disease or partial remission, predict disease progression with a considerable lead-time. Improved effectiveness i n breast cancer management can be seen when TPS is used in combination with CA 15-3, When tumor marker determinations are applied properly in the appr opriate situation, the results can assist the oncologist. Thus monitoring o f therapy in patients with metastatic breast cancer should be based upon se rial TPS and CA 15-3 determinations in serum. The use of tumor marker deter minations in the early follow-up interval following surgery to detect early tumor recurrence may be simpler, more sensitive, and less expensive than i maging methods.