Value of CEA in breast cancer.

Plasma carcino-embryonic antigen (CEA) is elevated in a small percentage of patients with early breast cancer and in about 60% of patients when the disease is disseminated beyond regional lymph nodes. It is neither sufficiently sensitive or specific a test to be used for mass screening and is of limited use as a diagnostic aid. Monitoring of patients following mastectomy with serial estimations of plasma CEA is of little value in detecting disease recurrence before it becomes clinically apparent. Monitoring of CEA levels may be helpful in objectively assessing response to treatment in patients with disseminated breast cancer.