Hereditary Breast and Ovarian Cancer: Which Patients Are at High Risk?

Ellen T. Matloff, MS, CGC

Oncology nurses are in the unique position of intimately getting to know cancer patients, and their families, during a crisis and over a prolonged period of time. As a result, the relationships forged are based on deep-seated trust and respect. This bond allows many patients to share their deepest fears with their oncology nurses: “Will I die of my cancer? Will I lose part of my body? Will I be able to get through chemotherapy?” And perhaps the darkest and most frightening, “Does this mean my children will get cancer?” The oncology nurse can play a critical role in helping patients and their entire families find the answer to these questions.

Approximately 90% of cancer is not hereditary, meaning it is not caused by a single gene mutation. However, as we learn more about genetics and our testing techniques advance to include hundreds of genes, we may learn that a greater proportion of all cancer is at least in part due to inherited genetic changes. Learning how to recognize which patients in your practice are at greatest risk and require a referral to cancer genetic counseling and testing will be a critical way in which oncology nurses can contribute to the field of cancer genetics.

Table 1. Risk Factors for Hereditary Breast and Ovarian Cancer

Refer to genetic counseling if the patient has a personal and/or family history of:

Breast cancer diagnosed before the age of 45

Multiple cases of breast cancer, pancreatic cancer, or ovarian cancer on the same side of the family

Even one case of ovarian cancer in a family with breast cancer

Male breast cancer

The combination of breast, ovarian, and/or pancreatic cancer in one bloodline

The combination of breast, ovarian, and/or pancreatic cancer in a single individual (eg, an individual diagnosed with both breast and ovarian or breast and pancreatic cancer)

Jewish ancestry in combination with any of the above

Jewish ancestry and one case of breast (at any age), pancreatic, or ovarian cancer (even in the absence of additional family history)

Known genetic mutation in the family (eg, BRCA1, BRCA2)

In addition, medullary breast cancer and triple negative breast cancer are over-represented in women with hereditary breast and ovarian cancer

Which of My Patients Are at Increased Risk for Hereditary Breast or Ovarian Cancer?

A personal history of early-onset, medullary, or triple-negative breast cancer alone means that your patient is at increased risk for a hereditary form of cancer. This simple list of risk factors can steer your referrals for genetic counseling and testing (Table 1).

In the frenzy of a cancer finding, imaging, a biopsy, surgery, and treatment, the risk of a hereditary cancer can get lost in the mix. Yet, this piece of information is often essential in surgical and radiation decision making. For this reason, patients at increased risk should be offered genetic counseling and testing before having surgery and radiation, whenever possible.

Patients at high risk for hereditary cancer who were diagnosed with their cancers >10 years ago and were not referred for genetic counseling are still at risk. This information can help prevent a new primary cancer and help to protect family members from developing cancer. These patients should be referred for genetic counseling, even decades after a diagnosis. The oncology nurse can be crucial in “connecting these dots.”

Table 2. Dispelling Myths About Genetic Counseling and Testing

Myth: Breast and ovarian cancer can only be inherited from your mother.

Fact: We can inherit these mutations from either parent with equal frequency. We can pass these mutations on to sons and daughters with equal frequency.

Myth: Genetic counseling and testing is not covered by health insurance.

Fact: Most health insurance companies cover these services for patients at high risk.

Myth: My health insurance company will discriminate against me and my family if I have genetic testing.

Fact: We have laws, such as the Genetic Information Nondiscrimination Act (GINA), protecting against this form of discrimination. Violations have not been widely reported in the past 15 years.

Myth: I've already had cancer, so testing can't help me.

Fact: This information can help patients avoid a second primary cancer and can be critical to other family members.

Myth: I'm the only one in my family who has had cancer, so it is not hereditary.

Fact: Even if one person has any of the risk factors listed in Table 1, she is at significantly increased risk for a hereditary form of cancer.

Myth: I don't need genetic counseling. I just want the blood test.

Fact: One of the greatest risks of genetic testing is the risk that the wrong test will be ordered, or that the result will be misinterpreted. Every patient needs genetic counseling by a qualified provider, both before and after testing.

Many patients–and clinicians–have widespread misconceptions about genetic testing that prevent them from seeking care. The oncology nurse can help to dispel these myths (Table 2).

The field of genetic testing is expanding rapidly, and more and more patients are now candidates for testing. This testing will guide surveillance, risk reduction, management, and surgical and radiation decision making as we move forward. The oncology nurse will play a key role in finding patients who need genetic counseling and testing, dispelling myths about this field, and facilitating referrals to genetics professionals.

Ellen T. Matloff, MS, CGC, is a certified genetic counselor and director of Cancer Genetic Counseling at Yale Cancer Center, New Haven, Connecticut.