Carcinoembryonic antigen and interferon as tumor markers in breast cancer

A total of 239 determinations of CEA plasma levels were performed for 83 breast cancer patients during chemotherapy or follow-up. In addition, 137 plasma samples were assayed for interferon levels. Patient clinical status was carefully scored according to objective criteria and recorded at each evaluation. Liver function tests (LFT) were performed to establish a full clinical picture at each visit. The results obtained proved a 73 to 83% positivity rate when the results of the 4 tests were compared. The importance of routine CEA assays and careful clinical evaluation and LFT are stressed. An analysis of interferon levels defined 4 distinct groups that differed by the amount of interferon present and also by clinical status and CEA levels. The results are discussed in terms of tumor volume-dependent interferon production.