Genetic Education, Counseling, and Nursing Management. After completing her pedigree (Figure 1), you tell her you will share her family history with the oncology care team. Following a discussion with the oncology care team, you and the oncologist talk with the patient about her family history. You tell her that her family history suggests hereditary breast/ovarian cancer associated with mutations in the BRCA1 and BRCA2 genes, which are transmitted in an autosomal dominant pattern. You also let her know that individuals who are of Ashkenazi Jewish ancestry have a higher chance of having an inherited susceptibility to breast and ovarian cancer. You recommend a referral to a genetics specialist who can evaluate her personal and family history and talk with her in detail about genetic testing for mutations in BRCA1 or BRCA2. The patient agrees to see the genetic specialist, and you make the referral that day.
You learn from the genetic specialist several weeks later that your patient and her family have agreed to pursue genetic testing. The genetic specialist explains to you that it is most informative to test an affected family member first for mutations in BRCA1 or BRCA2 to learn whether a gene mutation is associated with the cancer in the family. Your patient's sister has agreed to genetic testing and the results are pending. You learn from your patient several weeks later that her sister was found to have a BRCA1 gene mutation, 185delAG, which is one of the three specific mutations that are found in a greater frequency in persons of Ashkenazi Jewish heritage.
You explain that there are several gene mutations in BRCA1 and BRCA2 that are more common in individuals of Ashkenazi Jewish ancestry. These are called founder mutations. Founder mutations are gene mutations that are more frequent in specific populations derived from a small isolated ancestral group in which, generations ago, one or more people carried a gene mutation. The genetic testing that you and the healthcare team recommend will include these founder mutations, including the mutation 185delAG that has been identified in your patient's family. Your patient decides to proceed with genetic testing to learn whether she carries a BRCA1 or BRCA2 mutation. You arrange for a follow-up visit with your patient in a month.
At the follow-up visit, your patient tells you that she has been found to have the same BRCA1 mutation as her sister. She expresses deep concern and tells you “I want to do whatever I can to keep from getting breast or ovarian cancer.” You explain to her that you and the oncology team will talk with her about her options for screening to reduce her risk of breast and ovarian cancer. You and the team meet with the patient to review her cancer risk management options, which are intensive screening, chemoprevention, and/or risk-reducing surgery. Breast cancer screening involves a combination of monthly breast self-exams, annual or semiannual clinical breast examination, annual mammograms, and annual breast magnetic resonance imaging (MRI).
Screening of her ovaries will involve annual or semiannual pelvic examination, annual or semiannual transvaginal ultrasound examination, and annual serum CA-125; however, ovarian cancer screening has not been shown to consistently detect ovarian cancer early. Therefore, when childbearing is complete, removal of the ovaries is considered. The patient tells you and the team that she and her husband do not plan to have any more children. She is also told that she has the option of chemoprevention using tamoxifen(Drug information on tamoxifen), which has been shown to reduce the risk for breast cancer by approximately 50%. However, the oncologist informs her that it is not yet clear whether women with a BRCA1 mutation derive the same risk-reduction benefit from tamoxifen.
The oncologist also discusses the option of risk-reducing surgery, removal of her breasts and ovaries to reduce as much as possible her risk of those cancers. Also discussed is that women with a mutation who are premenopausal at the time of risk-reducing oophorectomy reduce their breast cancer risk by approximately 50% and that following oophorectomy, the use of tamoxifen does not add any additional reduction in breast cancer risk.[34–36] Therefore, if she opted for risk-reducing oophorectomy, chemoprevention would not be considered.