Actress's double mastectomy shines a light on genetic causes of breast cancer
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Christina Applegate, the Emmy Award winning actress who starred in Married ... with Children, was recently diagnosed with early stage breast cancer. She has since undergone a double mastectomy and is now reportedly cancer-free. Applegate's cancer was discovered through magnetic resonance imaging (MRI). It's a test not commonly performed on women because it is expensive and can detect false abnormalities.
But in Applegate's case it proved to be a good idea and perhaps a lifesaver. That's because the 36-year-old actress tested positive for one of the "breast cancer genes", BRCA-1. Though breast cancer is relatively uncommon in young women, this is not the case in women with BRCA-1 or BRCA-2, said Suzanne Mahon, DNSc, genetic counseling specialist and assistant professor of hematology and oncology at Saint Louis University School of Medicine. Being BRCA positive means having about a 90 percent lifetime risk of breast cancer overall compared to the general population's 12-13 percent, Mahon said.
About 95 percent of new cases and 97 percent of breast cancer deaths occur in women age 40 and older and the average age at diagnosis is 61, according to the American Cancer Society. Though family history of the disease is an important risk factor, most cases of breast cancer are not genetically linked. In fact, only 5-10 percent of breast cancer cases are genetic. However, of these hereditary cancers, approximately 85 percent are due to BRCA-1 and BRCA-2, Mahon said.
To Screen or Not to Screen...
...That is the question. Breast cancer screening has historically involved breast exams, both self and clinician-directed, and mammography. "Most [guidelines] recommend mammograms starting at the age of 40," said Jen Invanovich, a genetic counselor at Barnes-Jewish Hospital.
Applegate's MRI may represent a new standard of care for patients at high-risk. The American Cancer Society recommends that any women with a lifetime cumulative risk of over 20 percent should have MRI screening in addition to mammogram, Invanovich said.
Several models have been developed for the purpose of predicting breast cancer risk. The one most widely known is the Gail model. According to the Gail model, an individual risk score is calculated by incorporating factors, such as the number of close relatives with breast cancer, age at first period and first child born, and then multiplying the relative risks from these categories by an adjusted population risk for breast cancer.
Ultrasound may also be appropriate as an additional screening technique, depending on the individual. Screening with MRI and/or ultrasound "needs to be tailored to the individual and based on factors such as breast density." Invanovich said. "The current recommendations only include mammography and MRI which has shown to be a better than mammography alone."
It's in the Genes
Genetic testing for the BRCA genes is recommended for people with multiple family members diagnosed with breast and/or ovarian cancer, those with young age of onset, which is under the age of 40, Mahon said. It is most effective for the person diagnosed with cancer to be tested for BRCA. If negative, family members do not need to be tested.
Before getting genetic testing, Mahon said there are three parameters all major organizations agree on:
- That there is a greater than 10 percent chance of having the mutation
- That someone is available to explain the pro's and con's of testing
- And that the information from the testing would change the patient's care.
Clearly in Applegate's case it did.
Applegate chose to have both of her breasts removed and reconstructed. This is no small decision, not only due to the emotional implications, but also because the surgery itself is not without risk. Breast reconstruction is often performed in multiple steps over time.
Another issue not specifically addressed in the Applegate case is the increased risk of ovarian cancer. "At age 40, if done having children, we are also recommending an oophorectomy," said Mahon. "Ovarian cancer is difficult to detect and the treatments are not overly effective either."
The general risk of ovarian cancer is about 1.7 percent, compared with 16 to 60 percent of women with altered BRCA-1 or BRCA-2 genes, according to the National Cancer Institute. Screening includes regular pelvic exams, ultrasound, and a blood test.
Some lifestyle behaviors may decrease breast cancer risk. These include eating well, exercising regularly and limiting alcohol consumption. Other techniques, such as preventive medications, may be available and should be discussed with a trusted specialist.
A positive test result for BRCA-1 or BRCA-2 has important health and social implications for the individual as well as their family members, including any current and future children. Those found to have the gene(s), whether or not they get cancer, may pass it and the increased risk of cancer to their sons and daughters. And it's not just the emotional costs that are high. While "Medicare has criteria for coverage, Medicaid and other insurance are more variable," said Mahon. And "it is about $3175 to get tested."
Dr. Cindy Haines is managing editor of Healthday-Physician's Briefing and president of Haines Medical Communications Inc., a full-service medical communications and consulting firm. As a board-certified family physician, Haines is well-versed in all areas of health care, with particular interest in fitness, nutrition, and psychological health.
Her weekly column on health care issues will appear here each Friday, and you can listen to Dr. Haines' House Call on KTRS.
This column by HealthDay's Dr. Cindy Haines, managing editor of the Physician's Briefing news service, runs each week in the St. Louis Beacon. To contact her, contact Beacon health editor Sally J. Altman.