About Carcinoembryonic Antigen (CEA)The carcinoembryonic antigen is a protein that shows up in your blood, and is normally found in the tissue of a developing fetus. After birth, the mother's blood levels of CEA should disappear. Smoking produces higher than normal levels of CEA, so you should abstain from smoking for several days prior to your test.
Normal and Abnormal Results of Your CEA Test
A normal value of CEA is a range from 0 to 2.5 micrograms per liter (mcg/L). For a smoker, expected levels of CEA range from 0 to 5.0 micrograms per liter (mcg/L). High levels of CEA may be an indication of cancer, but some people will test high, even though they do not have cancer. The results of a CEA test must be considered along with your symptoms, general health, lifestyle factors and the results of other tests.
Uses For the CEA Blood Test
Doctors may use the CEA blood test for a variety of reasons:
- Test for possible cancer
- Measure the effectiveness of cancer treatment
- Catch an early recurrence
- Determine possible metastasis
American Society of Clinical Oncology. ASCO Patient Guide: Tumor Markers for Breast Cancer. Last Updated: October 22, 2007.