CEA (synonym: carcinoembryonic antigen) is a so-called tumor marker.Tumor markers are substances produced naturally in the body by tumors and are detectable in the blood. They can provide an indication of a malignant neoplasm and are used as a follow-up test in cancer aftercare.CEA is considered the most important tumor marker for colon carcinoma (cancer of the large intestine). The specificity (probability that actually healthy persons who do not suffer from the disease in question are also identified as healthy in the test) is approximately 90 %. However, it may also be increased in many other diseases.
The procedure
Material needed
- Blood serum
Preparation of the patient
- Not necessary
Disruptive factors
- None known
Standard values
| Non-smoker | < 40 years | < 3.8 μg/l or ng/ml |
| > 40 years | < 5.0 μg/l or ng/m | |
| Smoker | < 40 years | < 5.0 μg/l or ng/m |
| > 40 years | < 6.5 μg/l or ng/m |
Values of > 20.0 μg/l or ng/ml raise suspicion of tumor disease (cancer).
Indications
- Suspected colon carcinoma (colon cancer; CEA level is an independent prognostic tumor marker and should be determined preoperatively)
- Therapy control (follow-up) of colon carcinoma.
- Suspected medullary thyroid carcinoma (thyroid cancer).
- Differential diagnosis of liver tumors (primary liver tumor or metastasis).
- Therapy control (follow-up) of breast carcinoma (breast cancer).
- Detection of tumor progression after surgical treatment.
Interpretation
Interpretation of increased values
- Colon carcinoma (tumor marker of 1st choice) – specificity circa 90%!
- Bronchial carcinoma (lung cancer).
- Gastric carcinoma (stomach cancer)
- Mammary carcinoma (breast cancer)
- Esophageal carcinoma (cancer of the esophagus)
- Ovarian cancer (ovarian cancer)
- Pancreatic carcinoma (pancreatic cancer)
- Thyroid carcinoma (thyroid cancer)
Slightly increased in
- Bronchitis – inflammation of the bronchi.
- Chronic inflammatory bowel disease such as Crohn’s disease or ulcerative colitis.
- Diverticulitis – inflammation of diverticula in the intestine; these are mucosal protrusions through the muscular layer of the intestine
- Liver diseases such as cirrhosis – connective tissue remodeling of the liver with associated functional impairment.
- Cystic fibrosis – genetic disease associated with the formation of excessively viscous mucus, affecting mainly the lungs and digestive tract.
- Nicotine abuse (nicotine dependence).
- Pancreatitis (inflammation of the pancreas)
- Pneumonia (pneumonia)
- Smokers
Interpretation of lowered values
- No diagnostic significance
Further notes
- In malignant (malignant) disease, there is a higher probability of the presence of a tumor from 4 times the standard value for CEA. If the reference value is exceeded by more than 8 times, malignant disease is considered certain.
- In benign diseases (eg, in inflammatory liver disease, liver cirrhosis, pancreatitis, inflammatory gastrointestinal diseases / gastrointestinal diseases) is usually an increase in CEA up to a maximum of 4 times the normal value.
- In smokers, an increase in CEA up to 20 μg/l or ng/ml may occur.
- Highly pathologic levels are usually present in cases of large tumor mass or metastasis.
