High Risk Breast Cancer Care

Breast Cancer Genetics and Genomics

Mercy doctors review each patient’s case and order the appropriate genetic testing to diagnose and aid our treatment of the cancer. Gene mutations may be inherited or acquired. Due to recent technical advances, we now have the ability to rapidly sequence the entire genome of a tumor and identify many abnormalities.

About 8 percent of breast cancers are related to the BRCA1, BRCA2 and PALB2 genes, which predispose individuals to developing cancer. Nine other mutations  TP53, PTEN, Peutz-Jeghers Syndrome, CDH1, PALB2, CHEK2, ATM, NBN, BARD1) also increase lifetime risk for breast cancer. If you carry one of these genes, your treatment recommendations can be impacted.

Reasons to Consider Genetic Testing

As these genes run in families, it is important to gather as much information as you can about the cancers in your family. This includes all cancers, not just breast, on both your mother’s side and father’s side. Mercy follows the NCCN (National Comprehensive Cancer Network) guidelines when recommending testing. These guidelines are regularly updated as more information becomes available and are considered standard of care, so talk to your doctor about whether you need to consider testing.

Patients already diagnosed with breast cancer should also consider undergoing genetic testing. Mercy follows the ASBS (American Society of Breast Surgeons) recommendation that every patient with breast cancer should undergo genetic testing. We have the ability to rapidly sequence the entire genome of a tumor and identify many abnormalities. This includes HER2 testing, which allows us to use targeted anti-HER2 therapy to treat the cancer. We now have FDA-approved medications (PARP inhibitors) to treat BRCA(+) HER2 - metastatic breast cancer. Targeted treatment therapy is typically paired with more traditional treatments such as chemotherapy and radiation.  

Types of Genetic Testing

A blood sample is analyzed and results are reviewed with the patient to determine treatment options, prevention or early detection strategies, and the need to screen other family members. Mercy routinely uses panel testing to identify genes that predispose people to breast cancer. The Myriad myRisk Hereditary Cancer Test uses sophisticated technologies and proprietary algorithms to evaluate 29 clinically significant genes associated with eight hereditary cancers including: breast, colon, ovarian, endometrial, pancreatic, prostate and gastric cancers, and melanoma. Increased surveillance with early screening with regular mammography – and, in some cases, breast MRI – may be recommended.

Risk Reduction

Mercy’s breast surgeons and general surgeons who treat breast disease are well positioned to propose individual management strategies for those who test positive for a genetic mutation. Risk reduction with medication, lifestyle changes and in some cases surgery may be recommended.

Clinical Studies

Clinical trials offer cancer patients new hope for successful treatment. Mercy is committed to offering a variety of opportunities for patients to participate in research studies. Learn more.