Overview of common tumor markers

Tumor markers are specific substances that can be detected in blood or body fluids and are used to assist in cancer screening, diagnosis and monitoring of efficacy. According to clinical use, it can be divided intoprotein(such as AFP, CEA),carbohydrate antigen(such as CA125, CA19-9),Enzymes(such as PSA) andgene class(such as HER2). Among them, AFP and CEA are suitable for early screening of liver cancer and colorectal cancer, CA125 and CA19-9 are commonly used in gynecological and digestive tract tumors, and PSA is a specific marker for prostate cancer. Different markers have different sensitivities and specificities, and a comprehensive judgment needs to be made in conjunction with imaging and other examinations.

protein tumor markers

Protein markers are the most widely used category in clinical practice.Alpha-fetoprotein (AFP)Mainly used for liver cancer screening, normal values are usually lower than 20 ng/mL, and elevated values may indicate hepatocellular carcinoma or germ cell tumors.Carcinoembryonic Antigen (CEA)It is related to gastrointestinal tumors such as colorectal cancer and gastric cancer, but its specificity is low. Smoking or inflammation may also cause a slight increase. In addition,Prostate-specific antigen (PSA)is a core indicator of prostate cancer, but benign prostatic hyperplasia may also interfere with the results. Such markers require dynamic monitoring, and a single detection is of limited significance.

carbohydrate antigen tumor markers

Carbohydrate antigens reflect the presence of tumors by detecting changes in sugar chains on the cell surface.CA125is an important indicator of ovarian cancer, but endometriosis can also cause false positives;CA19-9It is closely related to pancreatic cancer and cholangiocarcinoma, but may also be elevated in patients with chronic pancreatitis.CA15-3andCA27.29Commonly used for breast cancer surveillance, but early sensitivity is low. Such markers are more used for efficacy evaluation rather than early diagnosis and need to be confirmed with imaging.

Other types of markers and precautions

Enzyme markers such asNeuron-specific enolase (NSE)It has high specificity for small cell lung cancer, and genetic markers such asHER2/neuandBRCA mutationsCan be used to guide targeted therapy. It should be noted that tumor markerscannot be used alone as a basis for diagnosis, both false positives and false negatives exist. For example, CEA may be slightly elevated in smokers, while some patients with early-stage cancer have normal levels of the marker. Therefore, clinical judgment needs to be comprehensively combined with medical history, physical examination and multidisciplinary examination.

Summary and clinical significance

Tumor markers are important tools in cancer management, but they need to be used scientifically. High-risk groups (such as patients with family history or chronic diseases) can regularly screen for markers with higher specificity such as AFP and PSA; patients during treatment can monitor recurrence through CA125, CEA, etc.; genetic testing can guide personalized treatment. When selecting markers, it is necessary to consider their applicable cancer types and limitations to avoid over-reliance on a single indicator. Currently, Roche, Abbott and other companies provide related testing products, such asElecsys series(Roche) andARCHITECT(Abbott).

Quote source:
1. "Handbook of Clinical Oncology" (5th edition), American Society of Clinical Oncology (ASCO)
2. World Health Organization (WHO) Tumor Marker Application Guidelines
3. Roche Diagnostics official website: Elecsys tumor marker detection system
4. Abbott China: ARCHITECT Immunoassay Analyzer Product Description