What’s the difference between Genomic and Genetic Testing?

“Genomic” and “genetic” are often used interchangeably in popular media and common speech. However, in breast cancer diagnostic testing, genomic and genetic testing have different meanings.

Genomic testing involves looking at specific genes in a tumor to find out what is driving its growth and behavior. Genetic testing involves looking at the genes a person is born with, and is used to determine whether there is an inherited risk or hereditary predisposition for cancer.

Genomic Testing of Breast Cancer

Genomic testing is done on the tumor tissue itself. It provides you and your doctor information on how your specific cancer is behaving: Is your breast cancer likely to have spread beyond the breast and lymph nodes?

Genetic Testing for Breast Cancer

In comparison, genetic testing is done on normal cells, from blood, saliva, or buccal swab (cheek swab) and is often used when speaking about hereditary disease. It is the presence of a defective gene that indicates whether you have an inherent risk for developing a disease. For instance, being found to have a defective BRCA gene means you have an increased risk of breast cancer, and a 50% chance (1 in 2) of passing this gene to the next generation.1

MammaPrint Genomic Testing

MammaPrint is a genomic test for women with early-stage breast cancer that helps predict the risk of spread beyond the breast and lymph nodes, the risk of distant metastasis. MammaPrint may identify patients at low genomic risk of distant metastasis who are unlikely to have significant benefit from chemotherapy. MammaPrint is currently the only FDA cleared test for risk of recurrence within five years in women of all ages that provides a personalized high or low risk result.

[1] American Cancer Society: https://www.cancer.gov/about-cancer/causes-prevention/genetics/brca-fact-sheet