An Oncology Nurse’s Primer on Genomics and Biomarker Terminology

June 17, 2020

With the massive paradigm shift in cancer therapy to precision medicine (, the use of biomarkers and biomarker testing has also rapidly evolved to guide treatment selection. However, the terminology used in genomics is complex and inconsistent, and patient advocacy organizations recommend using a common taxonomy to prevent confusion among patients and providers alike. Nurses spend more time with patients and families than any other member of the healthcare team and can reinforce common language and terminology. As a nurse, here are the terms you need to understand.

What Is a Biomarker?

In the broadest sense, a biomarker is a molecule that can be measured in blood, other bodily fluids, or tissues. A biomarker can be an indicator of normal or abnormal biologic processes, such as in cancer. Traditional biomarkers such as lactate dehydrogenase and prostate specific antigen are simple and inexpensive tests that provide valuable information across the cancer care continuum. Assessing for novel biomarkers via new technologies has allowed for ( identification of genomic and epigenomic alterations underlying carcinogenesis.


Biomarkers can be classified as somatic (i.e., indicative of the acquired cellular and genomic alterations that drive cancer pathogenesis) or germline (i.e., indicative that the genomic alteration is present from birth and in every cell of the body). Other biomarkers demonstrate appropriateness of immune checkpoint inhibitors, such as PD-L1 expression.

The U.S. Food and Drug Administration (FDA) created the BEST (Biomarkers, EndpointS, and other Tools) resource ( as a classification system to decrease confusion and to increase consistent use of terms. It categorizes biomarkers as follows:

There are a host of biomarkers associated with specific cancer types, disease diagnosis or prognosis, and treatment decisions and monitoring. Some biomarkers are not tumor-specific (also known as tissue- or tumor-agnostic (

Dozens of FDA-approved therapies require biomarker testing in the labeling. Some common biomarkers include:

Diagnosis, treatment selection, recurrence, and relapse detection is now biomarker driven ( in many cancers. Oncology nurses must learn the biomarker terminology and classification schemas so they can accurately discuss biomarker results with patients and families.

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