What are tumor markers used for?

Introduction

Tumor markers are substances, often proteins, produced by cancer cells or by the body in response to cancer. These markers are found in the blood, urine, or tissue samples and are instrumental in oncology for diagnosing and monitoring various types of cancer.

Understanding Tumor Markers

Tumor markers aid in understanding cancer pathology. They are not only used for the detection of malignant conditions but also for staging, prognosis, and monitoring therapy efficacy. Tumor markers can be specific to a particular type of cancer or can span across different types.

For instance, carcinoembryonic antigen (CEA) is utilized in various carcinomas, while prostate-specific antigen (PSA) is specific for prostate cancer.

Types of Tumor Markers

1. Cancer Antigens

• CA-125: Commonly used for ovarian cancer detection.
• CA 19-9: Predominantly used for pancreatic cancer.

2. Enzymes

• Lactate Dehydrogenase (LDH): Non-specific marker, increased in various malignancies.

3. Hormones

• Calcitonin: Primarily used to monitor medullary thyroid cancer.

4. Oncofetal Proteins

• Alpha-fetoprotein (AFP): Utilized in testicular and hepatic cancers.

Clinical Applications of Tumor Markers

Tumor markers are pivotal in the clinical workflow of oncology applications, including:

• Screening: PSA testing for prostate cancer in asymptomatic individuals.
• Diagnosis: Elevated levels of CA-125 aiding in the diagnosis of ovarian cancer.
• Prognosis: High levels of AFP indicating aggressive liver cancer.
• Monitoring Treatment: Decline in CEA levels post-chemotherapy suggesting treatment efficacy.
• Recurrence Detection: Rise in CA 19-9 levels indicating potential recurrence of pancreatic cancer.

Company Solutions

Numerous companies provide solutions for tumor marker tests. Some of these are:

1. Roche Diagnostics

Roche offers a wide array of tumor marker tests, such as Elecsys® CA 15-3 II and Elecsys® CA 19-9 that target breast and gastrointestinal cancers respectively.

2. Abbott Laboratories

Abbott's Alinity i platform facilitates the use of markers like AFP and PSA to streamline cancer diagnosis and monitoring.

3. Siemens Healthineers

Siemens provides a comprehensive menu for tumor marker testing, including assays for CEA and Beta-hCG with advanced detection limits.

4. Thermo Fisher Scientific

The company’s BRAHMS KRYPTOR compact PLUS offers an automated test solution for calcitonin, aiding medullary thyroid cancer management.

References

1. Hoffman RM. PSA Testing for Prostate Cancer Screening. N Engl J Med 2011; 365:2013-2019.
2. American Cancer Society. Tumor Markers: Tests. 2023.
3. Roche Diagnostics. Tumor Markers. Corporate Resources, 2023.
4. Siemens Healthineers. Laboratory Diagnostics, 2023.