Breast cancer screening recommendations have evolved over the past decade. BRCA1/2 genes are tumor-suppressor genes. Mutations in these genes place women at an increased risk for developing breast, ovarian, fallopian tube, and peritoneal cancer. Detection of BRCA1/2 mutations through genetic screening can provide patients with more information about their cancer risk and can lead to discussion of prophylactic therapies. This includes increased screening frequency, medical therapy, and surgical interventions.
Dr. Neil Skolnik (left) and Dr. Alyssa Style
New USPSTF recommendations address who is at an increased risk for BRCA1/2 mutations. They recommend using screening tools focusing on family history that primary care physicians can utilize to determine who should be referred for genetic counseling to discuss the risks and benefits of genetic screening. The following are the task force’s two primary recommendations:
The USPSTF recommends that primary care clinicians assess women with a personal or family history of breast, ovarian, tubal, or peritoneal cancer or who have an ancestry associated with BRCA1/2 gene mutations with an appropriate brief familial risk assessment tool. Women with a positive result on the risk assessment tool should receive genetic counseling and, if indicated after counseling, genetic testing. (B recommendation)
The USPSTF recommends against routine risk assessment, genetic counseling, or genetic testing for women whose personal or family history or ancestry is not associated with potentially harmful BRCA1/2 gene mutations. (D recommendation)
Breast cancer is the second leading cause of cancer and cancer death for women in the United States. Ovarian cancer ranks fifth in cancer deaths for women in the U.S. By age 70, women with BRCA1/2 mutations have a 45%-65% cumulative lifetime risk of developing breast cancer.
Mutations in BRCA1, specifically, are associated with a 39% lifetime risk for ovarian, fallopian tube, and peritoneal cancer. In contrast, mutations in BRCA2 are associated with a 10%-17% lifetime risk.
The USPSTF also underscores the increased prevalence of BRCA1/2 mutations in the Ashkenazi Jewish population. Three out of seven familial risk assessment tools inquire about Jewish ancestry. This is because the Ashkenazi Jewish population have a higher prevalence of three founder mutations in the BRCA1/2 gene. A member of this population has a 1 in 40 chance of carrying one of these three mutations, whereas the general population has a 1 in 300 chance.
The USPSTF recommends a multistep process of screening. The first step is taking a family history of cancer. For women who have a family history of breast, ovarian, tubal, or peritoneal cancer or a personal history of these cancers, a brief familial risk assessment tool should be used to determine the need for referral for in-depth genetic counseling to determine the need for genetic testing.
It is important to recognize that the validated tools recommended by the USPSTF are specific for genetic risk assessment. General breast cancer risk assessment tools, including the National Cancer Institute Breast Cancer Risk Assessment Tool, which is based on the Gail model, are not recommended.
The sensitivity of the tools recommended by the USPSTF range between 77% and 100%. A number of tools are given as an option with no one tool being better than the other. Perhaps the easiest to implement of the validated tools recommended is the Pedigree Assessment Tool. For this tool, points are assigned for every family member with breast or ovarian cancer as indicated in the table below.
A positive result on a screening tool will lead primary care physicians to appropriately refer patients for genetic counseling. Genetic testing for BRCA1/2 mutations should be limited to those individuals whose personal and/or family history reflects an increased risk for gene mutations after detailed genetic assessment and counseling. The results of the genetic screening should assist a patient in their decision making.
Prophylactic treatment for BRCA1/2 mutation carriers are outside the scope of this recommendation. However the guidelines briefly review risk-reducing therapies including screening, medical, and surgical options. Medical therapy for patients who have BRCA1/2 mutations include the use of tamoxifen, raloxifene, and aromatase inhibitors. Surgical interventions include bilateral mastectomy and salpingo-oopherectomy.
Screening options include earlier and more frequent mammograms and breast MRIs. Screening is largely based on family history and the USPSTF acknowledges their uncertainty when screening women with an unknown family history. Male breast cancer, pancreatic cancer, prostate cancer, and melanoma are also associated with BRCA1/2 mutations. They are not included in this recommendation.
The bottom line
USPSTF recommended that primary care physicians should use familial risk assessment tools to screen women for BRCA1/2 mutations. This includes women with a personal and/or family history of breast, ovarian, tubal, or peritoneal cancer or women with a family history of BRCA1/2 gene mutations. Patients who test positive through one of the suggested screening tools should be referred for genetic counseling. This could lead to genetic testing and subsequent prophylactic therapies and/or increased screenings if the patient so desires. It is of importance to note the USPSTF recommends against routine screening of BRCA1/2 gene mutations for women who do not meet the above requirements.
Reference
USPSTF Recommendation: Assessment, counseling, and testing for BRCA-related cancer. JAMA. 2019;322(7):652-65. doi: 10.1001/jama.2019.10987.
Dr. Style is a second-year resident in the Family Medicine Residency Program at Abington (Pa.) Jefferson Health. Dr. Skolnik is professor of family and community medicine at Jefferson Medical College, Philadelphia, and an associate director of the family medicine residency program at Abington Jefferson Health.