Genetic Testing for Breast Cancer
What is BRCATrue®?
1 in 8 women are affected by breast cancer in their lifetime
1 in 71 women are affected by ovarian cancer in their lifetime
80% of families with a pattern of breast and ovarian cancer have been attributed to BRCA1/2 mutations
Pathogenic variants in the BRCA1 gene are associated with hereditary breast and ovarian cancer (HBOC) syndrome, and convey a significantly increased risk of both breast and ovarian cancer. Studies have demonstrated that BRCA1 gene pathogenic variants can be associated with up to a 85% breast cancer risks and up to a 63% ovarian cancer risk in high-risk Furthermore, women with a BRCA1 pathogenic variant have an increased risk of a second breast cancer diagnosis (contralateral or ipsilateral). This risk has estimated to be up to 27% within the first 5 years of diagnosis and up to 40-50% within 20 years of initial diagnosis. Pathogenic variants in BRCA1 may also be associated with an increased risk of other types of cancer, including peritoneal, pancreatic, prostate, and male breast cancer. However, the exact level of risk is not yet known. 5-12
Pathogenic variants in the BRCA2 gene are associated with Hereditary Breast and Ovarian Cancer (HBOC) syndrome, and convey a significantly increased risk of several cancers, including breast, ovarian, pancreatic, melanoma, and prostate cancer. Studies have demonstrated that BRCA2 gene pathogenic variants can be associated with up to an 84% breast cancer risk and up to a 27% ovarian cancer risk in high-risk Furthermore, in women who have had breast cancer, having a BRCA2 pathogenic variant increases risk of a second breast cancer diagnosis (contralateral or ipsilateral). This risk has estimated to be up to 12% within the first 5 years of diagnosis and up to 40–50% within 20 years of initial diagnosis. BRCA2 pathogenic variants may also be associated with small increased risks of developing primary peritoneal, gallbladder, bile duct, and stomach cancer. However, these risks are not yet clearly defined. 5-14
Inheritance and Familial Implications
BRCA1 and BRCA2 pathogenic variants are inherited in a dominant pattern, meaning that anyone with a pathogenic variant has a 50% chance of passing it on to each of his or her children. Conversely, this also means that they have a 50% chance of not passing on the pathogenic variant to each child. Individuals who carry a BRCA1 or BRCA2 pathogenic variant do not have any control over whether or not a variant is passed on to their children. Both men and women can have pathogenic variants in BRCA1 or BRCA2 and can pass them down to their children, even though the cancer risks may be different for males and females. In addition to children, each first-degree relative (parents and full siblings) of someone with a BRCA1 or BRCA2 pathogenic variant has a 50% chance to have the same pathogenic variant.
Genetic testing is available to at-risk family members to determine if they also carry the identified BRCA1 or BRCA2 pathogenic variant. Because of the increased risks for certain cancers, identified carriers of the BRCA1 or BRCA2 should seek recommendations from their provider regarding future medical management. Those individuals found not to carry the familial BRCA1 or BRCA2 gene pathogenic variant will have risks similar to the general population.
The test is best suited for individuals with either a history of early onset breast or ovarian cancer or a strong family history of breast and/or ovarian cancer. Individuals with the following medical or family history factors should consider testing for mutations in BRCA1/2:
In the process of sequencing the patient’s DNA, we may identify a likely pathogenic genetic variant, or a genetic variant with uncertain pathogenicity (VUS). To help understand the significance of these types of variants, and how the patient and family members may be affected, Pathway Genomics offers a Familial Studies Program. Testing additional family members for the same variant observed in your patient, and determining the correlation between cancer history and occurrence of the variant, may provide further insight into the clinical relevance of the variant.
Pathway Genomics classifies variants using a 5-tier system based on the American College of Medical Genetics (ACMG) guidelines. Likely Benign and Benign variants are not reported.
Mutations with known clinical significance and demonstrated to increase the risk of cancer
Genetic changes that have some preliminary clinical data suggesting an association with cancer but not sufficient to make a definitive determination of pathogenicity and associated cancer risk
Uncertain Pathogenicity (VUS) | Genetic changes with either conflicting data or no supporting data, thus a determination of pathogenicity cannot be made
Genetic changes with strong but limited evidence to be classified as benign and are not likely to increase the risk for cancer
Genetic changes that are previously reported and have sufficient evidence to be classified as benign with no clinical relevance
BRCATrue® must be ordered by a physician, and patients are required to fill out a clinical history questionnaire to determine eligibility.
Physicians can request test kits here.
Patient’s saliva or blood sample is collected in the BRCATrue® test kit and sent back to Pathway Genomics, along with the required paperwork.
Pathway Genomics analyzes your sample in its CLIA-certified and CAP-accredited laboratory. Typically within two to three weeks, your personalized results will be available to the ordering health care professional. The results will then be released to you. Pathway Genomics has a team of genetic counselors who are available to ensure that you understand the information in your report, and to answer any questions you may have about your results . To contact our genetic counselors, please call our client services department at 877-505-7374 or email firstname.lastname@example.org.