It is estimated that 182,000 women in the United States will be diagnosed with invasive breast cancer in 2008. Breast cancer is the second most common cancer among women in the United States. (The first is skin cancer.) Symptoms of breast cancer may include a lump in the breast, a change in the size or shape of the breast and discharge from a nipple.
Breast cancer is the second leading cause of cancer death in women. (Lung cancer is the first.) In a 2006 study, it was determined that even though 12 to 29 percent more white women are diagnosed with breast cancer than African-American women, African-American women are 28 percent more likely to die from the disease.
Between 5 and 10 percent of breast cancers are thought to be linked to gene mutations, including but not restricted to changes in the BRCA1 and BRCA2 genes. Women with these mutations have a 36 to 85 percent lifetime risk for breast cancer and a 16 to 60 percent lifetime risk for ovarian cancer, depending on the group of women studied. This is in contrast with the 12 percent lifetime breast cancer risk and 1.8 percent lifetime ovarian cancer risk in the general population. Currently, it is unclear whether the chances of developing these cancers are related to the specific mutation identified in a family or whether additional factors, like genetic and environmental, affect how the disease develops. It is generally accepted, however, that carriers of mutations in BRCA1 and BRCA2 have an excessive risk for both breast and ovarian cancer and that those individuals should take into account more intensive preventive and screening strategies.
One in 40 Ashkenazi Jews carry a BRCA mutation, about 10 to 15 times higher than the general population. Seventy to 80 percent of women who get breast cancer do not have a family history of the disease.
» Anna Newlin, CGC
» American Cancer Society
» us Department of Health and Human Services — Health care for minority women: Breast and cervical cancer screening and treatment
» Medline Plus: Breast Cancer
It is estimated that 21,000 women will be diagnosed with ovarian cancer in 2008. Ovarian cancer is the eighth most common cancer in women (not counting skin cancer). It ranks fifth as the cause of cancer death in women. Symptoms may include pain in the lower abdomen, bleeding from the vagina, weight gain or loss, abnormal periods, unexplained back pain that gets worse, bloating, nausea, vomiting and trouble eating.
Overall, the prognosis for ovarian cancer remains poor, with a 45 percent five-year survival rate. Approximately 15,280 women die every year in the United States from ovarian cancer.
Most cases of ovarian cancer are not explained by any known risk factors, and early detection is difficult given the difficulties associated with ovarian cancer screening. Most ovarian cancers happen after menopause. Half of all these cancers are found in women over the age of 63.
Ovarian cancer risk is higher among women whose close blood relatives have or have had this disease. About one in 10 cases of ovarian cancer are linked to a hereditary predisposition.
The chance of a woman with a BRCA1 or BRCA2 mutation developing ovarian cancer is 16 to 60 percent. For the general population, the chance is 1 to 1.8 percent. Women who have had breast cancer have a higher risk of ovarian cancer.
» Anna Newlin, CGC
» American Cancer Society
» Medline Plus: Ovarian Cancer
» eMedicine: "Ovarian Cancer" by Agustin A Garcia, MD, associate professor of medicine, University of Southern California's Keck School of Medicine
» Genetic Health: Screening Procedures for Ovarian Cancer
» Cara Tenanbaum, Ovarian Cancer National Alliance
» Allison Werner-Lin, Ph.D.
BRCA1, BRCA2 and Genetic Testing
In 1990, Dr. Mary-Claire King first identified an association between an area on chromosome 17 and an increased risk for breast cancer. By 1994, a location on chromosome 13 was also linked to an increased risk for breast and ovarian cancer. Since then, scientists working for Myriad Genetics as well as independent scientists identified the location of the specific genes, BRCA1 and BRCA2, short for breast cancer 1 and breast cancer 2. As the first company to sequence BRCA1 and BRCA2, Myriad owns the patents to the genes. Therefore, for consumers who want to be tested for mutations in BRCA1 or BRCA2, the genetic testing must be performed by Myriad Genetics.
It is well established that alterations in BRCA1 and BRCA2 are involved in many cases of hereditary breast and ovarian cancer and that both women and men can carry the alteration. In addition, a third possible genetic location has been recently identified. There are three different results you can get from the testing:
- Positive for a deleterious mutation — The test can come back positive, indicating that a person does carry an alteration in the gene, increasing the risk for cancer.
- No mutation detected — The testing can come back negative, indicating that the person does not carry an alteration in either gene; however, the test does not detect all alterations.
- Variant of uncertain significance — The test can come back indicating that there is a change in the gene, but it cannot be determined if the change is one that would actually increase the risk for cancer; this is called a variant of uncertain significance. Not all changes found in genes cause the gene to function improperly.
To complicate the situation, research also indicates that not all BRCA mutations put women at risk for breast or ovarian cancer.
Testing for mutations in the BRCA1 and BRCA2 genes is especially recommended in families that have a history of breast or ovarian cancer diagnosed at younger ages. A positive test indicates a significantly increased risk for the diseases. However, a negative test for the mutation does not mean that a woman will never develop breast or ovarian cancer.
A study published by the American Medical Association found that African-American women with a family history of breast or ovarian cancer were significantly less likely than white women to undergo genetic counseling for BRCA1 and BRCA2 testing. When the results of a genetic test reveal a BRCA mutation, individuals are counseled about prevention. For example, it is recommended that women who carry a BRCA mutation avoid environmental factors that can increase their risk for cancer, such as smoking. In addition, individuals are presented with choices about their medical management, including:
- Surveillance — This includes regular clinical monitoring, such as transvaginal ultrasounds and blood testing for CA125, an ovarian cancer marker, to try to detect ovarian cancer early; mammograms; breast MRIs; and clinical exams to try to detect breast cancer at its earliest stage, starting at age 25 or five to 10 years earlier than the earliest known case of breast cancer in the family (whichever is earlier).
- Prophylactic surgery — This entails removing at-risk tissue with preventive mastectomy (removal of healthy breasts) and preventive salpingo-oophorectomy (removal of healthy fallopian tubes and ovaries). It is estimated that in both premenopausal and postmenopausal women, a preventive mastectomy reduces the risk of breast cancer by 90 percent and the removal of healthy fallopian tubes and ovaries reduces the risk of ovarian and peritoneal cancers by more than 90 percent.
- Chemoprevention — This entails the use of drugs like tamoxifen to reduce the risk of cancer, though it is unclear whether this is effective in women with a BRCA1 or BRCA2 alteration.
- Gene therapy — At this time no gene therapy exists to repair the BRCA1 or BRCA2 gene.
- Lifestyle — The use of birth control pills decreases the risk of developing ovarian cancer, especially among women who use them for several years. Some studies estimate the reduction of risk to be 30 to 50 percent.
» Mayo Clinic
» National Cancer Institute
» National Human Genome Research Institute
» Armstrong et al., "Racial Differences in the use of BRCA1/2 Testing Among Women With Family History of Breast or Ovarian Cancer," American Medical Association (2005)
» Ovarian Cancer National Alliance
» Cathy Wicklund, NSGC
On May 21, 2008, more than a decade after its introduction, the Genetic Information Nondiscrimination Act (GINA) was signed into federal law by President George W. Bush. Hailed as the first civil rights legislation of the new millennium, GINA ensures comprehensive protection against genetic discrimination in health insurance and employment settings. The insurance provisions within GINA will go into effect in May 2009, and the employment provisions will go into effect in November 2009.
Legislation on genetic nondiscrimination was first introduced in the 1995-1996 session as part of the Health Insurance Portability and Accountability Act (HIPAA), but various versions of bills to protect those with family histories of genetic alterations from discrimination had never managed to pass the House and Senate in the same year — until May 2008.
The lack of protection against genetic discrimination was of concern because research indicated that up to one-quarter of women eligible for BRCA1 and BRCA 2 testing declined it, citing concern over insurance discrimination as one of their main reasons for their declination.
According to the National Cancer Institute, "Genetic discrimination occurs when people are treated differently by their insurance company or employer because they have a gene alteration that increases their risk of a disease, such as cancer." Without protective legislation, employers were able to deny employment based on the results of genetic tests or a family history indicating the presence of a mutation (even if an individual's test was negative for that mutation). Information included in a person's medical records could also be used by insurance companies to deny health or disability insurance and to exclude from coverage treatments needed to address hereditary conditions.
Several states have outlawed genetic discrimination by employers and health insurance companies, but without GINA, the degree of discrimination protection has varied from state to state and test results safely obtained in one state might not remain private in another.
Some federal protection is provided by the Americans With Disabilities Act of 1990. In 1995, the Equal Employment Opportunity Commission included in its definition of "disabled" those who carry genes that might put them at risk for disease. HIPAA also offers some protection against medical records being released without a person's permission or knowledge, but it does not address situations in which records are released "voluntarily," as when applying for insurance coverage and certain jobs.
» Coalition for Genetic Fairness
» National Human Genome Research Institute
» Peterson, et al., "Health Insurance and Discrimination Concerns and BRCA1/2 Testing in a Clinic Population," Cancer Epidemiology Biomarkers & Prevention Vol. 11, pp. 79-87 (January 2002)
» L.A. Times: The Nation; Senate backs privacy for genetic data; The landmark bill would shield people from insurance and job discrimination based on test results. (Paid content)