Oncomarker CA 19-9. Analysis of CA 19-9: the norm and when it is elevated

Oncomarker CA 19-9 is a high molecular weight glycoprotein. It is produced by cells in the epithelium of the digestive system. Immunochemiluminescence analysis is used as a method of investigation. CA 19-9 is associated with cancer pathologies.

general information

Venous blood is used as a biological material for research. CA 19-9 is an effective tumor marker. Its definition is used in the diagnosis, monitoring and early detection of metastasis in the stomach, pancreas, liver, intestines (thick and straight). The level of CA 19-9 was elevated in almost all patients with GI tract tumors, especially the pancreas. Developed in the cells of tumors, glycoprotein penetrates into the systemic bloodstream. Observing and evaluating its content, specialists are able to follow the course of pathology. Analysis of CA 19-9, the norm of which in a healthy person is not more than 10 U / ml, is not used in the initial diagnosis.

What is pancreatic cancer? Brief information

This cancer is currently on the list of the most dangerous pathologies. About 90% of patients die already in the first year of the onset of the disease. At the time of diagnosis, 80% of patients show distant or regional metastases. Specialists attribute this, mainly, to the hidden course of pathology. The disease is often masked by the inflammatory processes of chronic course in the organs of the hepatopancreatoduodenal zone (cholelithiasis, cholecystitis, chronic pancreatitis). In this regard, it is necessary to carry out differential diagnosis as early as possible, eliminating the presence of malignant neoplasms. This, in turn, will allow choosing the most effective therapeutic tactics of these chronic pathologies.

Antigen SA 19-9. Concentration

With cancer in the pancreas, a high level of glycoprotein is noted. The analysis of CA 19-9, the norm of which is indicated above, is necessary in the detection of carcinoma, assessment of the possibility of resection. At concentrations greater than 1000 U / ml, neoplasm is considered operable in only 5% of patients. If the content is below this number, the tumor can usually be removed. However, after intervention for one to seven months, there is a risk of recurrence. The CA 19-9 cancer marker is considered to be the second most important marker after CEA for detection of malignant neoplasm in the stomach. In addition, the study of high-molecular glycoprotein is additionally assigned to alpha-fetoprotein in the diagnosis and monitoring of liver cancer, biliary tract and bladder cancer.

Increase content

Elevated levels of glycoprotein can be noted against a background of various inflammatory and benign pathologies in the liver and digestive system (up to 500, but more often up to 100 units / ml), as well as cystic fibrosis. In the first case, the concentration was increased in 12% of patients. The maximum level is not more than 45 U / ml. Glycoprotein is excreted with bile. In this regard, any cholestasis may be accompanied by an increase in its content. In such cases, it is necessary to conduct simultaneously a study of GGT (gamma-glutamate transferase) and alkaline phosphatase. Increase in concentration can be observed against a background of tumors of other localization (with colorectal cancer, ovarian tumor), hepatic pathologies (cirrhosis, hepatitis).

Absence or reduced level

Specialists note that normal concentration does not exclude the presence of malignant neoplasm in the pancreas. In this case, the early stage of the pathology can be diagnosed, when the level has not yet risen. In conducting an investigation for patients receiving treatment, a decrease in the glycoprotein content may indicate the effectiveness of therapeutic measures.

What is research needed for?

The test for the oncomarker CA 19-9 is necessary for monitoring the effectiveness of therapeutic measures for pancreatic cancer, as well as for the timely detection of recurrences of pathology. The study allows differential diagnosis of malignant neoplasm with other diseases (for example, pancreatitis). The indicator CA 19-9 indicates the prevalence of malignant process, the presence of distant metastases on the background of cancer.

In which cases is the study assigned

The test for the oncomarker CA 19-9 is recommended for the manifestation of symptoms of cancer in the pancreas: nausea, abdominal pain, jaundice, weight loss. The study is scheduled periodically for patients with an initially high level of glycoprotein concentration and receiving treatment. The analysis is recommended for suspicion of cancer in the gallbladder or bile duct, liver, stomach or large intestine. Research in this case is assigned in conjunction with other tests.

Explanation

The reference values, in the range of which the antigen level should be, is 0-35 U / ml. As already mentioned above, a high concentration of glycoprotein indicates the presence of a malignant process in the pancreas. At the same time, the higher the content, the more recent the stage of pathology. Excessively high levels indicate tumor metastasis.

Important information

The test for the content of the glycoprotein in question is of particular importance in the early detection of metastasis of a malignant neoplasm in the pancreas. About 7-10% of people do not have a gene that encodes this high molecular weight glycoprotein. Accordingly, in the body there is no genetic opportunity to synthesize the antigen CA 19-9. Thus, even with the diagnosis of malignant neoplasm, the level of this glycoprotein is not determined in serum.

additional information

Before you donate blood, experts recommend not smoking for half an hour. Diagnostic value of the test increases with simultaneous examination at CEA. In addition, tests for CA 72-4, total bilirubin, CA 242 are recommended for the most accurate diagnosis and the appropriate treatment required. Laboratory experts are appointed by specialists such as hepatologist, therapist, surgeon or oncologist.

Conclusion

Experts note that today, pancreatic cancer is more common in patients after 30 years. This pathology is considered one of the most difficult to diagnose and poorly treatable. In this regard, the most sensitive tests are needed to detect it. Unfortunately, the study of antigen concentration can not be used to diagnose the initial stages of the development of the disease. But nevertheless, this test remains the most sensitive and informative for evaluating the effectiveness of treatment, revealing the early stage of metastasis of a malignant neoplasm. Undoubtedly, the specialist uses the results of various diagnostic measures during the survey. In addition to laboratory, the patient is assigned and instrumental research. The most accessible of them today is ultrasound. At its carrying out the expert can reveal a tumor in the size from two centimeters. To determine the size, position, as well as the spread of malignant process, designate a CT scan. Using this method, a tumor measuring three centimeters can be detected. At the same time, it should be noted that the CT is associated with a certain dose of X-ray radiation. Therefore, this study is not carried out often or as a preventive measure. MRI has a smaller load on the patient's body. But this kind of research is not carried out by persons who have any metal implants. All these diagnostic measures along with blood tests can identify early stages of development or metastasis of cancer in the pancreas.