Carcinoembryonic antigen or CEA is a protein produced early in fetal life and during rapid multiplication of the cells of the digestive system, mainly, and can then be used as a marker of colorectal cancer. However, people without any gastrointestinal changes or smokers may have increased concentrations of this protein, so other tests are necessary to confirm the diagnosis of the tumor.
The CEA exam is more commonly used to follow the patient under treatment for colorectal cancer, and normalization of the concentration of this protein may be observed after about 6 weeks after surgery, for example. This protein may also be increased in people who have changes in the pancreas, liver and even breast, and is indicative of breast dysplasia. Learn more about breast dysplasia.
Reference values
The reference value for the CEA examination varies according to the laboratory, so it is recommended that the dosage of the carcinoembryonic antigen is always done in the same laboratory to allow a more accurate interpretation of the examination and the clinical picture of the patient. The CEA reference values usually are:
- In smokers: up to 5.0 ng / mL;
- In non-smokers: up to 3.0 ng / mL.
The blood concentration of CEA may be slightly increased in people without any malignant change, for example, however when the value is 5 times higher than the reference value, it may be indicative of cancer with possible metastasis. Therefore, it is important that other tumor markers are measured and evaluated, as well as the blood count and biochemical tests for the diagnosis to be completed. Find out what the tests are for cancer.
What is it for
Carcinoembryonic antigen or CEA is usually required to aid in the diagnosis of colorectal cancer. However, because of its low specificity, other tests are necessary to confirm the diagnosis, and CEA is the most used to follow the patient after the operation and verify the response to chemotherapy treatment, for example. Know the symptoms of bowel cancer.
In addition to being indicative of gastrointestinal cancer, CEA may also have its concentration increased in other situations, such as:
- Pancreatic cancer;
- Lung cancer;
- Liver cancer;
- Inflammatory bowel disease;
- Thyroid cancer;
- Pancreatitis;
- Pulmonary infections;
- Non-smoking only;
- Benign breast disease, which is characterized by the presence of benign nodules or cysts in the breast.
Because of the various situations in which CEA may be elevated, it is recommended that further examinations be performed so that the diagnosis can be made correctly.
