In recent years, the incidence of tumor patients has increased year by year, and with people's understanding of tumors, tumor markers have also become a mandatory item in many people's physical examination projects. So, in the face of so many tumor indicators, how to identify their clinical significance? Next, let's learn about the clinical significance of tumor marker detection
Tumor markers are a type of substance that is synthesized, released, or raised by the body's response to tumor cells.
Tumor markers exist in blood, cells, tissues or body fluids, reflecting the presence and growth of tumors, and measuring tumor markers by immunology and genomics methods has certain value for the diagnosis, efficacy and recurrence of tumors, and the judgment of prognosis. Tumor markers mainly include protein, carbohydrate, enzyme and hormone tumor markers.
Protein tumor markers
Alpha-fetoprotein (AFP) assay
Alpha-fetoprotein is a serum glycoprotein synthesized in the early stages of the fetus, and after birth, the synthesis of AFP is inhibited. When malignant lesions occur in liver cells or germ gonadal embryonic tissues, cells that synthesize AFP ability begin to synthesize again, resulting in a significant increase in the AFP content in the blood. Therefore, the detection of AFP concentration has important clinical value for the diagnosis of hepatocellular carcinoma and trophoblastic malignancy.
Reference value: <25 μg/L
Clinical significance: 1. primary liver cancer; 2. germ gonadal embryonic tumor; 3. viral hepatitis, cirrhosis (usually < 300 μg/L).
Carcinoembryonic antigen (CEA) assay
The cea content in the body after birth is extremely low, and it is a broad-spectrum tumor marker that can be expressed in a variety of tumors. It is mainly used for the diagnosis, prognosis, efficacy monitoring and tumor recurrence of auxiliary malignant tumors.
Reference value: <5 μg/L
Clinical significance:1. Elevated CEA is mainly seen in patients with pancreatic cancer, bowel cancer, stomach cancer, lung cancer, etc.; 2. Dynamic observation decreases when the concentration decreases when it improves, and vice versa; 3. It is related to smoking In smoking patients, CEA is slightly increased.
Tissue polypeptide antigen (TPA) assay
The level of TPA in the blood is closely related to the degree of cell division and proliferation, and the higher the level of TPA in the serum, it is often used clinically for the auxiliary diagnosis of rapidly proliferating malignancies, especially for the monitoring of the efficacy of known tumors.
Reference value: 130U/L
Clinical significance: 1. The serum TPA level in patients with malignant tumors can be significantly increased; 2. The TPA level decreases after improvement, and if it is raised again, it indicates recurrence; 3. TPA and CEA are detected simultaneously to facilitate the differential diagnosis of malignant and non-malignant breast tumors.
Prostate-specific antigen (PSA) assay
Elevated serum PSA levels may be seen in prostate cancer. 80% of the total serum PSA (t-PSA) is present in the binding form, called complex PSA (c-PSA); 20% is present in the free form, called free PSA (f-PSA). Elevated t-PSA and f-PSA, while f-PSA/t-PSA ratio decreased, suggest prostate cancer.
参考值:t-PSA<4.0μg/L, f-PSA<0.8μg/L,f-PSA/t-PSA>0.25
Clinical significance: 1. Prostate cancer; 2. If the t-PSA concentration is not significantly reduced or increased again after prostate cancer resection, it indicates tumor metastasis or recurrence; 3. Digital examination, prostate massage, and cystoscopy will cause PSA to rise.
Squamous epithelial cell carcinoma antigen (SCC) assay
SCC is a subtype of the tumor-associated antigen TA-4 and is a glycoprotein
Reference value: < 1.5 μg/L
Clinical significance: 1. Lung squamous cell carcinoma, cervical cancer, esophageal carcinoma; 2. Some benign diseases such as psoriasis and other skin diseases, renal insufficiency, upper respiratory tract infections, etc. can also cause an increase in SCC concentration; 3. Sweat, saliva and other body fluid pollution will lead to false positives.
Cytokeratin 19 fragment (CYFRA 21-1)
Tissues or organs rich in epithelial cells, such as lungs, breasts, bladder, intestines, etc., are mainly distributed in tissues or organs, and when these tissues undergo malignant changes, the level of CYFRA 21-1 in the blood can be seen to be elevated. At present, it is mainly used for the differential diagnosis and prognosis assessment of non-small cell lung cancer.
Reference value: <2 μg/L
Clinical significance: 1. Is the preferred tumor marker for non-small cell lung cancer; 2. In addition to lung cancer, CYFRA 21-1 can also be seen in breast cancer, bladder cancer, colorectal cancer, etc.; 3. Other benign diseases such as pneumonia, tuberculosis, gastrointestinal diseases, etc. can be seen, but their levels are mildly elevated (generally < 10 μg/L).
Glycolipid tumor markers
Cancer Antigen 50 (CA50)
It is a tumor glyco-like antigen that is not organ-specific for tumor diagnosis.
Reference value: < 20,000 U/L
Clinical significance: 1. increased pancreatic cancer, gallbladder (tract) cancer, primary liver cancer, etc.; 2. Dynamic observation of its level is valuable for cancer tumor efficacy, prognosis judgment, recurrence monitoring; 3. Distinguish benign and malignant chest and abdominal effusions are valuable; 4. In chronic liver disease, pancreatitis, bile duct disease, CA50 is also elevated.
Cancer Antigen 724 (CA724)
CA724 is a tumor-associated glycoprotein that is a marker of gastrointestinal and ovarian tumors.
Reference value: <6.7 μg/L
Clinical significance: 1. Increased increase in ovarian cancer, colorectal cancer, gastric cancer, pancreatic cancer; 2. Combined detection with CA125 can improve the detection rate of ovarian cancer; 3. Joint detection with CEA can improve the sensitivity and specificity of gastric cancer.
Glyco chain antigen 199 assay (CA199)
CA199 is a glycoprotein, and trace amounts of CA199 are present in the epithelial cells of normal human salivary glands, prostate, pancreas, mammary glands, etc.
Reference value: < 37,000 U/L
Clinical significance: 1. Preferred tumor marker of pancreatic cancer; 2. Can be seen in acute pancreatitis, acute hepatitis, gallbladder carcinoma, bile duct cancer, gastric cancer, colon cancer, etc.; 3. Continuous detection is of great value for disease progression, surgical efficacy, prognosis estimation and recurrence diagnosis; 4. Combined with CEA detection, improve the diagnosis rate of gastric cancer.
Cancer Antigen 125 (CA125)
Cancer antigen 125 (CA125) is present in epithelial ovarian cancer tissues and in the serum of patients.
Reference value: < 35,000 U/L
Clinical significance: 1. Present in ovarian cancer tissue cells and serous adenocarcinoma tissue, not present in mucus-type ovarian cancer; 2. Identification of pelvic tumors; 3. Cervical cancer, breast cancer, pancreatic cancer, lung cancer, cirrhosis decompensation period can also be elevated; 4. Some benign ovarian tumors, uterine fibroids Serum CA125 sometimes increases, but most do not exceed 100,000 U/L.
Cancer Antigen 153 (CA153)
Cancer antigen 153 (CA153) is a glycoprotein.
Reference value: < 25,000 U/L
Clinical significance: 1. Mainly used for the treatment monitoring and prognosis judgment of breast cancer patients; 2. The increase in concentration can also be seen in uterine fibroids, metastatic ovarian cancer, liver cancer, pancreatic cancer, colon cancer, lung cancer, bronchial cancer; 3. When mammary, liver, lung and other benign diseases, CA153 levels can also be seen to increase to varying degrees.
Enzyme tumor marker detection
Prostate acid phosphatase (PAP) assay
PAP is a glycoprotein found in the exocrine of the prostate.
Reference value: ≤2.0 μg/L
Clinical significance: 1. Serum PAP concentration is significantly increased in prostate cancer, and the degree of elevation is basically parallel to the development of cancerous tumor; 2. When the prostate is enlarged and prostatitis, the serum PAP level is elevated.
Neuron-specific enolase (NSE) assay
Reference value: < 15 μg/L
Clinical significance: 1. It has high value in the diagnosis and differential diagnosis of small cell lung cancer, and can be used to monitor the effect of radiotherapy and chemotherapy; NSE is a marker of neuroblastoma, and its sensitivity can reach more than 90%; 3. The presence of NSE in normal red blood cells affects the results of hemolysis in specimens.
Hormonal tumor markers
Calcitonin (CT)
Calcitonin (CT) is a hormone synthesized and secreted by thyroid follicular cells. Its main physiological effects are to inhibit the production of osteoclasts, promote bone salt deposition, increase urinary phosphorus, reduce blood calcium and blood phosphorus.
Reference value: <100ng/L
Clinical significance: 1. It is a specific and sensitive tumor marker for diagnosing and monitoring medullary thyroid carcinoma; 2. Other diseases: some lung cancer, breast cancer, gastrointestinal cancer and pheochromocytocellular carcinoma can increase serum calcitonin due to hypercalcemia or ectopic secretion, and occasionally increase serum calcitonin in patients with liver cancer and cirrhosis.
Selection of tumor markers
The same tumor can contain multiple markers, while a marker can present multiple tumors. The selection of specific markers or the best combination is conducive to improving the positive rate of tumor diagnosis, dynamic detection is conducive to the differentiation of benign and malignant tumors, and is also conducive to recurrence, metastasis and prognosis judgment.
Source: Medical Taste, Medical Bole
Edited by: Yeah Reviewer: Xiao Ran