Serial tumour markers serum carcinoembryonic antigen and cancer antigen 15-3 assays in detecting symptomatic metastasis in breast cancer patients.

The value of serum tumour markers in the prognosis of patients with breast cancer is controversial. This prospective study in Yazd, Islamic Republic of Iran, assessed the value of the tumour markers carcinoembryonic antigen (CEA) and cancer antigen (CA) 15-3 in 159 patients with primary breast cancer. CEA and CA15-3 assays (mean 14 per patient) were performed at diagnosis, end of surgery and chemotherapy and every 3 months in the first 2 years and every 6 months in second 2 years of the follow-up period. During follow-up, 33 patients (20.8%) presented symptomatic metastasis. A significant relationship was seen between metastasis status and positive CEA and CA15-3 levels. The sensitivity and specificity were 66.7% and 98.4% for CEA respectively and 84.8% and 91.3% for CA15-3 respectively. Optimum cut-offs were 4.95 ng/mL and 30.5 U/mL for CEA and CA15-3 respectively.