Placental isoferritin (PLF) in comparison with MCA and CEA in advanced breast cancer--first data from a pilot study.

The development of new and effective marker substances has optimized tumor-marker-guided follow-up programs to monitor generalization of disease and to assess the therapeutic outcome. Isoferritins of placental origin were first determined in the serum of patients with lymphoproliferative disease by way of the recently developed monoclonal antibody CMH-9. We have set up an Austro-Israeli working group and analysed 64 patients in terms of the sensitivity of placental ferritin (PLF) compared with the standard markers carcinoembryonic antigen (CEA) and mucinous-like cancer-associated antigen (MCA) in patients with metastatic breast cancer. We have additionally evaluated the importance of combined marker determination. Analysis of the data in view of site of metastatic spread yielded satisfying results both for PLF (sensitivity 70.4%) as well as MCA (sensitivity 76.9%) for visceral metastases; a combination of these two markers revealed a striking sensitivity of 88.4%, which, however, could not be improved by adding the third marker (CEA). With regard to non-visceral metastases, CEA and MCA were clearly superior.