Genetic and Biomarker Testing

Biopsy samples aresent for more testing. This testing looks at estrogen receptor and progesterone receptor status, HER2 status, and triple negative status, and genomic assays.

• Hormone status: Estrogen and progesterone are hormones produced in your body. Some tumors grow in response to these hormones. Treatment of these tumors may include medications like tamoxifen. Tamoxifen is a hormone therapy. These therapies block estrogen or progesterone. They keep the tumor from growing.
• Human epidermal growth factor receptor 2 (HER2): HER2 proteins control how cells grow. Some breast cancers can overproduce HER2. This over-production helps the tumor grow.⁸¹ Some drugs block this growth. Trastuzumab is an example of this kind of drug.
• Triple negative status: Some cancers do not use hormones or HER2 to grow. These cancers are called "triple-negative" cancers. Triple-negative breast cancers grow and spread quickly. This makes them difficult to treat. There are fewer targeted medicines to treat this kind of breast cancer.

• Genomic assays test the genes in the tumor. The activity of certain genes shows how likely the tumor is to grow and spread. They can help guide whether more treatments like chemotherapy will be needed after surgery. The number of genes that are tested varies.

Other factors will also impact your surgery and treatment decisions:

• BRCA1 and BRCA2 gene mutations make you more likely to have breast cancer. They also increase the risk of other cancers, including:⁴⁶
  • Ovarian
  • Fallopian tube
  • Pancreatic
  • Prostate
• Women in some ethnic groups have a higher chance of carrying a BRCA mutation. For example, about 1 of 40 Ashkenazi Jewish women carry a BRCA mutation.⁷⁶
• Pregnancy
• Previous radiation to the same area
• Prior lung disease
• Connective tissue disorders (like scleroderma)
• Systemic lupus erythematosus

The United States Preventive Services Task Force (USPSTF) recommends screening for women with family members with the following cancers:

• Breast
• Ovarian
• Tubal
• Peritoneal

Women who have had these cancers themselves should also be screened. Women with positive screening results should receive genetic counseling and/or BRCA testing.³⁰