BRCA1 & BRCA2: Indications for Testing & Interpreting Results

Genetic testing for breast cancer helps identify mutations in genes linked to tumor development, especially the BRCA1 and BRCA2 genes.

BRCA1 and BRCA2 are genes that produce proteins responsible for preventing abnormal cell growth. When mutations occur in these genes, the body’s ability to suppress tumor formation decreases, which increases the risk of developing breast cancer.

Besides testing for BRCA1 and BRCA2, it’s important to watch for early signs of breast cancer, such as a painless lump or mass, swelling, or changes in the size of one breast. If these symptoms appear, a breast specialist should be consulted for proper evaluation and diagnosis.

Indications for testing

A BRCA1 and BRCA2 genetic test is recommended for individuals with a personal or family history of breast, ovarian, tubal, or peritoneal cancer, or for those with ancestry known to carry BRCA mutations, such as Ashkenazi Jewish heritage.

Testing is also typically offered to anyone newly diagnosed with breast cancer at age 65 or younger, and to selected individuals over 65 based on personal and family history. People with a family history of breast cancer diagnosed before age 50, or of ovarian, pancreatic, or prostate cancer at any age, may also benefit from testing.

Before testing, a genetic counselor or qualified healthcare provider should evaluate your family history and discuss the potential benefits, limitations, and implications of the results.

How the test is done

The BRCA1 and BRCA2 genetic test is usually performed using a blood or saliva sample, which is sent to a specialized lab for analysis. No fasting or special preparation is required.

The type of analysis and mutations to be evaluated are determined by the doctor or genetic counselor. The test may examine the entire gene, specific regions of it, or identify known mutations in the BRCA1 and BRCA2 genes. In many cases, multigene panel testing is recommended to evaluate other genes that may also increase cancer risk.

The results are sent directly to the doctor or counselor and include details on the detection method used, as well as whether any variants were found. Depending on the testing technique, the report classifies results as pathogenic, likely pathogenic, variant of uncertain significance (VUS), likely benign, or benign. This helps the healthcare team assess cancer risk and determine the most appropriate preventive or treatment approach.

Test results

The BRCA1 and BRCA2 test results can be:

• Negative: No pathogenic mutations were found in the analyzed genes. This means the person has a lower risk of developing cancer, though it does not completely eliminate the possibility. Regular medical follow-up is still recommended.

• Positive: A pathogenic or likely pathogenic mutation was detected in at least one of the genes, indicating an increased risk of developing cancer. However, this does not necessarily mean cancer will develop or predict when it might occur. Additional tests, preventive strategies, and ongoing monitoring are recommended.

A BRCA1 gene mutation is linked to a higher risk of developing breast and ovarian cancer, while a BRCA2 mutation is associated with a greater likelihood of male breast cancer, prostate cancer, and pancreatic cancer.