What you need to know about tumor markers

Overview

A tumor marker is a substance found in the body that can be attributed to the presence of cancer. These markers can be present in the blood, urine, or body tissues of a patient. Tumor markers are produced by both cancerous cells and healthy cells, but their levels increase significantly when cancer is present. In this article, we will discuss the different types of tumor markers, their uses, potential limitations, and how tumor marker tests work.

Types of Tumor Markers

Tumor markers can be proteins, hormones, enzymes, antigens, or genetic material. Some common tumor markers include:

• Prostate-specific antigen (PSA): Associated with prostate cancer.
• Alpha-fetoprotein (AFP): Associated with liver cancer and some germ cell tumors.
• CA-125: Primarily associated with ovarian cancer, but also found in other cancers.
• Human chorionic gonadotropin (hCG): Associated with germ cell tumors.
• HER2/neu: A protein associated with breast cancer.

Uses of Tumor Markers

Tumor markers are used to help medical professionals with various tasks, such as:

• Screening: Used to detect cancer in its early stages, especially for high-risk populations.
• Diagnosis: Used to help determine if a mass is cancerous.
• Prognosis: Aids in determining the stage and aggressiveness of the cancer.
• Monitoring: Helps track the effectiveness of a treatment plan.
• Early detection: Alerts medical professionals to a possible recurrence of cancer after treatment.

Limitations

While tumor markers provide useful information, they do have limitations:

• False positives: Tumor markers can sometimes be elevated due to non-cancerous causes, leading to false-positive results.
• False negatives: Some cancers may not produce detectable levels of tumor markers, leading to false-negative results.
• Non-specificity: Tumor markers are often associated with multiple types of cancer, which can make them less useful for pinpointing a specific cancer type.

Tumor Marker Tests

Tumor marker tests typically involve analyzing a blood or urine sample, although tissue samples may also be taken in some cases. Results are usually available within several days, but the specific timeline may vary.

It's worth noting that tumor marker tests are not always definitive, and further testing may be required to confirm or refine diagnoses. Medical professionals will often use a combination of tumor marker tests, imaging studies, biopsies, and clinical symptoms to make a final determination.