Diagnostic usefulness of serum carcinoembryonic antigen determinations in breast cancer patients
Background and purpose: Carcinoembryonic antigen (CEA) is used as a tumour marker in breast cancer (BC). In order to assess diagnostic value of CEA in BC we examined its serum levels and frequencies of its increase in breast cancer patients (BCP), and compared them to those in controls. We also determined CEA in patients with metastatic and non-metastatic BC, and calculated sensitivity and specificity of CEA in BC.
Patients and methods: The main experimental group consisted of 47 female patients with histologically proved diagnosis of BC. There were two control groups: clinically healthy women, and female patients with other locations of cancer. Circulating levels of CEA were measured by means of immunoradiometric assay. Results were processed by means of t-test and two-way analysis of variance.
Results: Circulating levels of CEA, before treatment in BCP, were significantly higher (p<0.0001) than in healthy women, and in patients with other cancers (p<0.007), while serum CEA in other cancer patients was significantly higher (p<0.01) than in healthy control. There was a difference between frequencies of CEA increase in BCP and healthy women, while such a difference did not exist between BCP and other cancer patients. The circulating levels of CEA in metastatic BCP were significantly higher (p<0.03) in comparison to non-metastatic patients. Sensitivity and specificity of CEA in BCP was 65.0%, and 57.1%, respectively.
Conclusions: CEA does not have high tumour specificity for BC, since its circulating levels as well as frequencies of its increase may be elevated in patients with other types and locations of cancer, different from breast cancer. CEA can be detected in the serum of majority of patients with metastatic BC. CEA may be used as prognostic tumour marker in advanced BC.