Currently, there is a rapid increase in cancer incidence. First of all, this applies to neoplasms in the gastrointestinal tract. Therefore, it is important to know which tests will help to make this diagnosis. After all, cancer is not a sentence. With the timely appointment of therapy, stable remission can be achieved.
One of the effective methods for diagnosing tumors is an analysis of gastrointestinal tumor markers.
The essence of the survey
Gastrointestinal cancer markers are large molecules consisting of lipids, carbohydrates and proteins. They can be synthesized both directly by organs that underwent cancerous degeneration, and by healthy body tissues. In the second case, the production of these substances is a response to cancer aggression.
Most of the tumor markers belong to the group of organ-specific. That is, the detection of a specific substance in the blood indicates a lesion of a particular organ.
But it is fair to say that an increase in the number of tumor markers does not necessarily indicate the development of the cancer process. Therefore, it is very important to conduct repeated examinations and monitor changes in indicators over time.
Indications for examination
Assignment of the analysis to gastrointestinal tumor markers for everyone is not correct. After all, as already mentioned, in healthy people their level can be increased. Examination without reasonable reasons can lead to an incorrect diagnosis, which will undermine the psychological health of a person.
Therefore, before answering the question of which tumor markers should be taken for gastrointestinal diseases, it is necessary to explain the indications for this examination method:
- precancerous pathological processes in the intestine, stomach, pancreas and liver;
- the doctor has serious suspicions of gastrointestinal cancer;
- after surgery to check if the tumor tissue has been completely removed;
- when conducting antitumor chemotherapy to assess its effectiveness;
- to diagnose cancer metastasis or relapse before the development of the corresponding symptoms;
- to predict the further development of the tumor process.
Thus, the appointment of gastrointestinal cancer markers in cancer is necessary both for diagnostic and prognostic purposes.
Preparation for analysis and its implementation
Since the determination of the level of tumor markers is carried out in the blood, the preparation for this analysis is practically no different from that in other blood tests. In order for the analysis to have the greatest diagnostic value, one must adhere to the following rules:
- blood is given in the morning before eating;
- refuse food at least 8 hours before the examination;
- at least a day before analysis do not eat heavy foods: fatty, fried, smoked;
- immediately before analysis it is allowed to drink plain, non-carbonated water.
Venous blood is taken to diagnose tumors. For this, the nurse pre-treats the injection site with cotton wool with an antiseptic. After she takes a sterile disposable syringe and gently collects blood from a vein. A label with the patient’s data is glued onto the vial of blood, and the blood is sent to the laboratory for further counting the number of tumor markers.
The result is issued to the patient the very next day. In this case, the norm is indicated according to the data of a particular laboratory, and next to it is the level of the substance found in the patient's blood.
The final interpretation of the result and diagnosis is carried out by the attending physician. He evaluates the analysis data for window markers, the results of instrumental examination methods and the clinical manifestations of the disease comprehensively. Only with this approach to diagnosis can a correct diagnosis be made.
Types of tumor markers of the digestive tract
What gastrointestinal cancer markers should I take with the above indications? The following diagnostic types possess the greatest diagnostic value:
- CA 242;
- CA 125;
- CA 19-9;
- CA 72-4;
- CA 15-3;
- HCG - human chorionic gonadotropin;
- AFP - alpha-fetoprotein;
- CEA is a cancer-embryonic antigen.
Chorionic gonadotropin and alpha-fetoprotein are substances that may be present in humans in the norm. They are signs of pregnancy. A small amount is acceptable in non-pregnant women and men. But their high numbers and rapid growth indicate the development of the tumor process.
CA 242 and CA 19-9
When answering the question about which gastrointestinal tumor markers are the most informative for diagnosis, CA 242 and CA 19-9 should be noted. Usually these two substances are determined in a complex manner.
The concentration of CA 242 increases in the blood with a malignant tumor of the pancreas and intestines. Particularly characteristic is its detection in tumors of the rectum. But the level of the tumor marker can increase with inflammatory processes in the stomach and intestines, as well as with the growth of benign tumors. Therefore, when making a cancer diagnosis, this cancer marker is not determined in isolation, but together with CA 19-9.
The production of CA 19-9 occurs in the epithelial cells of the respiratory tract and gastrointestinal tract. Its blood level increases with cancer of the rectum, stomach and gall bladder. A slight increase in its quantity is also possible with other, non-oncological processes:
- cirrhosis of the liver;
- cholecystitis;
- hepatitis;
- cholelithiasis;
- pancreatitis
The development of cancer is indicated by a sharp and significant increase in the level of gastrointestinal cancer markers, as well as their progressive increase in dynamics.
CA 125, CA 72-4 and CA 15-3
CA 125 is synthesized by the epithelium of the digestive canal and respiratory tract in the fetus, and in adults only in the respiratory system. Its sharp increase is most characteristic of pancreatic cancer. It is also determined in malignant neoplasms of the liver, distal colon, stomach. Its slight increase is observed during pregnancy, severe liver diseases, inflammation of the pancreas and the inner layer of the uterus.
Determining the level of the gastrointestinal cancer marker CA 72-4 is carried out in the diagnosis of pancreatic carcinoma and intestinal tube. It is produced by the epithelial cells of the digestive canal. The development of the malignant process is evidenced by an increase in CA 72-4 along with CA 19-9, CA 125 and CEA. An isolated increase in CA 72-4 is possible with such non-cancerous conditions:
- benign breast tumor;
- benign ovarian tumors ;
- benign neoplasms of the lungs and liver;
- during pregnancy.
The oncological marker CA 15-3 is considered specific for the diagnosis of breast cancer. But its increase, along with other gastrointestinal cancer markers, indicates the development of cancer of the stomach or intestines. A minimal increase in the concentration of CA 15-3 is possible during pregnancy, rheumatism, HIV infection, impaired liver and kidney function.
HCG, AFP and CEA
Chorionic gonadotropin is a hormone that is produced by a small formation in the brain called the pituitary gland. The presence of this hormone is necessary for the normal course of pregnancy. A sharp increase in this substance in the blood of men or non-pregnant women is observed with carcinoma of the liver, stomach or intestines. In some women, its level rises sharply with menopause.
Alpha-fetoprotein is a substance that is synthesized in the fetus by the yolk sac, and in adults and children is produced by liver cells. An increase in the amount of alpha-veteroprotein in the blood along with an increased concentration of other gastrointestinal cancer markers indicates pancreatic cancer or liver carcinoma.
Cancer-embryonic antigen
The synthesis of cancer-embryonic antigen should be completely absent after the birth of the baby. Its residues are found in the epithelial cells of the stomach and intestines, respiratory tract. Its concentration increases with malignant neoplasms of the stomach and rectum.
A slight increase in its level is possible with autoimmune diseases of the connective tissue (rheumatism, systemic lupus erythematosus), the presence of cysts in the ovaries and mammary glands, and infection of the respiratory system. Also, its level in smokers is slightly increased.
Decryption analysis
The rate of oncological markers in the blood may vary depending on the laboratory in which the test was given. For example, in some laboratories the norm of the gastrointestinal marker CA 242 is up to 30 IU / ml, in others - up to 20 IU / ml. Average normal values are presented in the table below:
| CA 242 | up to 20 IU / ml |
| CA 19-9 | 40 IU / ml |
| CA 125 | 7 IU / ml |
| CA 72-4 | 20 - 30 IU / ml |
| CA 15-3 | 20 - 30 IU / ml |
| HCG | up to 10 IU / ml |
| AFP | 5 - 10 IU / ml |
| REA | 8 ng / ml |
Treatment methods
If an analysis revealed an increased level of gastrointestinal tumor markers in the blood, the doctor prescribes additional instrumental examinations: ultrasound, CT, scintigraphy. After the final diagnosis, the oncologist is determined with treatment tactics. Therapy of gastrointestinal malignancies depends on the prevalence and neglect of the process, the specific location and type of tumor.
The following methods of treatment of cancer of the digestive system are used:
- surgical treatment - resection of the affected part of the intestine or stomach, complete organ removal, liver transplantation;
- chemotherapy;
- radiotherapy;
- hormone therapy;
- targeted therapy.
In the last stages of cancer, palliative treatment is used. It is not able to completely cure the patient, but alleviates the symptoms and improves the quality of life.