Carcinoembryonic Antigen (CEA)
The carcinoembryonic antigen (CEA) test
measures the amount of this
protein that may appear in the blood of some people
who have certain kinds of cancers, especially large intestine (colon and rectal) cancer. It may also be present in people with cancer of the
pancreas, breast, ovary, or lung.
are usually available in 1 to 3 days.
The normal values listed here-called a reference range-are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what’s normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab.
Many conditions can change your CEA levels. Your
doctor will discuss any significant abnormal results with you in relation to
your symptoms and medical history.
Most cancers do not produce
this protein, so your CEA may be normal even though you have cancer.
- Cancer of the colon, lung, pancreas, breast,
or ovary may be present.
- Cancer may not be responding to
- Cancer may have returned after treatment. A steadily
rising CEA may be the first sign that cancer has come back after treatment.
Also, people with advanced cancer or cancer that has spread to other parts of
the body (metastatic cancer) may have high CEA levels if their original cancer
produced this protein before treatment.
- Another condition or
disease is present, such as
hepatitis, diverticulitis, inflammatory bowel disease,
peptic ulcer disease,
chronic obstructive pulmonary disease (COPD), inflammation of the gallbladder (cholecystitis), or an
obstructed bile duct.
What Affects the Test
Heavy smoking affects the test
What To Think About
- The CEA blood test is not reliable for
diagnosing cancer or as a screening test for early detection of
- CEA testing is a reliable test for recurrent colon cancer
if the original cancer produced this protein before treatment.
types of cancer do not produce a high CEA. Having a normal CEA level does not
mean that you do not have cancer.
- CEA levels usually return to
near-normal levels within 6 weeks of starting treatment if cancer treatment is
- Measuring the amount of CEA in other body fluids, such as
abdominal fluid (peritoneal fluid) or the fluid around the brain and spinal
cord (cerebrospinal fluid, or CSF), can determine whether
cancer has spread to that part of the body.
- Other diseases, such as
COPD, cirrhosis, and
Crohn's disease, may also raise CEA blood levels.
- CEA levels are usually higher in smokers than in people who do not