Indications for the appointment of blood analysis for CEA, what do the results mean, what diseases does it reveal and why is it performed?
A blood test for cancer-embryonic antigen is one of the most effective ways to detect cancer in the early stages. Malignant and benign neoplasms have a high mortality rate among patients. Timely detection of neoplasms of different etiology increases the chance of recovery of cancer patients.
This peptide compound was discovered in 1965 by Friedman in the large intestine affected by a malignant tumor. A little later it was proved that the antigen is localized in other places - the ovaries and the mammary gland. Therefore, the study is shown to women.
- What is the REA analysis, and what does the study show?
- Indications for blood test REA
- How is REA carried out?
- Norm of CEA in blood tests in men and women
- Increase in CEA in blood test: what does it mean?
What is the REA analysis, and what does the study show?
Analysis for carcinoembryonic antigen is a blood test used to diagnose and treat certain types of cancer. The blood test on CEA is used to detect colon and rectal cancer, to evaluate the effectiveness of cancer therapy.
Antigen is a peptide substance that is synthesized by cancer cells. Sometimes antigens are released into the bloodstream. The CEA analysis measures the amount of cancer-embryonic antigen in the blood. The increased amount of CEA in the human body after medical or surgical therapy indicates that the oncological disease recurs, or indicates that metastases appear in other organs.
Indications for blood test REA
The study of CEA indices in blood analysis has different applications. The doctor will prescribe an analysis if there are suspicions of cancer of various etiologies. The examination will help evaluate the effectiveness of cancer therapy methods. These treatments include surgery, chemotherapy, radiation, or a combination of these.
Analysis of cancer-embryonic antigen values is useful in the diagnosis of cancer, which secrete this peptide compound in large amounts. Not all kinds of oncological diseases produce REA in large quantities.
Elevated levels of cancer-embryonic antigen are found in diseases:
- Colorectal cancer.
- Medullary carcinoma of the thyroid gland.
- Malignant neoplasms of the breast.
- Cancer of the gastrointestinal tract.
- Malignant carcinoma of the liver.
- Lungs' cancer.
- Carcinoma of the ovaries.
- Malignant neoplasms in the pancreas.
- Prostate cancer.
The study of CEA indicators is ineffective for screening the general cancer population. Usually, the study is not used to check or diagnose healthy people who do not have a symptomatic complex. However, the presence of a genetic predisposition to colon cancer is a testimony to the study of cancer-embryonic antigen. But such cases are rare.
The doctor monitors the content of the cancer-embryonic antigen before the onset of therapy of oncological diseases. Such a procedure will establish basic values of CEA for the patient. One indicator of CEA is not an informative diagnostic method, but it has value in conjunction with other blood tests.
How is REA carried out?
The examination for cancer-embryonic antigen is carried out in the office of the attending physician. Blood is drawn from the vein on the arm. The process of obtaining blood includes:
- First, the nurse will clean the injection site with an antiseptic (ethyl alcohol).
- Then he will pull a tight tourniquet, which will allow the veins to swell. This process will facilitate the search for a vein on the arm.
- Then a needle is inserted into the designated area, to which the vial is attached.
- After filling the bottle, the needle is withdrawn and the site of the injection is re-cleared for preventive purposes.
- At the final stage, the material is sent to the laboratory, where the REA indicators are analyzed.
As with any blood test, there is a risk of bleeding, bruising, or infection at the injection site. Moderate or acute pain is felt with the injection. If other symptoms occur, consult your doctor.
Norm of CEA in blood tests in men and women
The norm of this indicator for men and women is 4 nanograms or less per milliliter of blood (ng / ml). In most healthy individuals, the content of this peptide compound is lower than the above value.
The norm for women and men is the complete absence of antigen. Its content in any quantity indicates the onset of pathological processes. The interpretation and norm of CEA indicators depend on the institution and the laboratory in which the analyzes were performed.
Increase in CEA in blood test: what does it mean?
The increase in the level of cancer-embryonic antigen depends on several factors. The content varies inversely with the degree of tumor; well-differentiated neoplasms secrete more CEA. This peptide compound increases more in tumors of the lymph nodes. Left-sided tumors usually have a higher level of CEA than right-sided tumors. Neoplasms that cause intestinal obstruction lead to higher levels of cancer-embryonic antigen. Aneuploid tumors produce more antigen than diploid tumors. Liver dysfunction increases the content of the indicator, since hepatocytes are the main metabolic site of CEA.
Antibodies to cancer-embryonic antigen are widely used in immunohistochemistry to identify cells expressing glycoprotein in tissue samples. In adults, CEA is expressed in cancer cells, especially in those that occur in the colon, lung, breast, stomach, or pancreas. This blood test is used for differential diagnosis with other diseases.
Elevated values of CEA is usually considered to contain more than 3 ng / ml. It should be emphasized that if a patient has a high level of antigen - this does not necessarily mean a cancer disease. There are other causes that increase the level of antigen:
- Infectious diseases (parasitic, bacterial, fungal, viral or other).
- Toxic damage to liver structures.
- Prolonged use of psychotropic substances.
- Inflammatory bowel disease of various genesis.
- Pulmonary infection.
- Peptic ulcer of the gastrointestinal tract.
- Pericarditis or myocarditis.
The concentration of carcinoembryonic antigen above 25 ng / ml is considered dangerous, and indicates a possible metastasis of a cancerous tumor. Smoking can affect the results of carcinoembryonic antigen tests. Before the study, it is necessary to exclude the use of psychotropic substances and medicines to reduce the likelihood of a false positive result.