TORRANCE (Nov. 13, 2007) - A new, simpler model for predicting breast cancer risk in postmenopausal women appears to be as accurate as a more complicated method currently used to decide if women would benefit from medication to reduce their risk of getting cancer, according to research published today in the Journal of the National Cancer Institute.
A team of researchers led by Rowan T. Chlebowski, a lead investigator at the Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center (LA BioMed), sought a simpler method for measuring breast cancer risk so women and their doctors could easily determine when the women would be likely to benefit from tamoxifen treatment for reducing their chances of getting breast cancer.
"For the first time, a postmenopausal woman can use a simple model and determine by herself if she is at increased risk of getting breast cancer,” said Dr. Chlebowski. “She could then raise this issue with her health care provider because interventions to reduce her risk of breast cancer are now available."
Using data from the Women’s Health Initiative, a 15-year research program involving 161,808 postmenopausal women and funded by the National Institutes of Health, the researchers found postmenopausal women were at an “increased risk” of developing breast cancer if they were: 55 years of age or older and had either had a breast biopsy at any time, regardless of findings, or had a first-degree relative (mother, sister or daughter) who had breast cancer diagnosed at any age.
"Increased risk" is defined as about a 2 percent risk of developing breast cancer over the next five years. The researchers sought a quicker and easier way to determine risk because those who are at “increased risk” may benefit from tamoxifen treatment to reduce their chances of getting breast cancer.
Prior to this study, most physicians relied on the “Gail Model” to determine risk. But it involves so many variables that a computer is needed to determine a woman’s risk of breast cancer. As a result, it wasn’t used widely.
Previous surveys found only 11 percent of California primary care physicians had used the Gail Model for risk assessment in the past year. In a national survey, only 16 percent agreed that it is “easy to determine” who is eligible for breast cancer risk reduction strategies and only 25 percent had prescribed tamoxifen for risk reduction in the past year.
The Gail model underestimated 5-year breast cancer incidence by almost 20 percent, but it performed better when predicting estrogen receptor-positive breast cancer than estrogen receptor-negative breast cancer. The simpler model that used only three factors for calculating risk—age, family history of breast cancer, and previous breast biopsy—was almost as accurate as the Gail model for predicting estrogen receptor-positive breast cancer.
The simpler model "would be more accessible for routine and rapid prescreening in the prevention or routine care setting," the authors wrote in the Journal article.
The article, entitled “Predicting Risk of Breast Cancer in Postmenopausal Women by Hormone Receptor Status,” appears in The Journal of the National Cancer Institute.
The Journal publishes peer-reviewed original research from around the world and is internationally acclaimed as the source for the most up-to-date news and information from the rapidly changing fields of cancer research and treatment. For the past several years, the JNCI has been ranked as the most-cited original-research cancer journal by the Institute of Scientific Information in its annual Journal Citation Reports. It may be viewed at http://jnci.oxfordjournals.org/
About LA BioMed
Founded more than 55 years ago, LA BioMed conducts biomedical research, trains young scientists and provides community services, including childhood immunization, nutrition assistance and anti-gang violence programs. The institute’s researchers conduct studies in such areas as cardio-vascular disease, emerging infections, cancer, diabetes, kidney disease, dermatology, reproductive health, vaccine development, respiratory disorders, inherited illnesses and neonatology.
LA BioMed researchers have invented the modern cholesterol test, the thyroid deficiency test and a test to determine the carriers of Tay-Sachs disease, an inherited fatal disorder. One of the institute’s researchers also developed the paramedic model for emergency care, setting a precedent that transformed emergency medical services and became the basis for training paramedics across the country.
Among LA BioMed’s current research programs are a major effort to develop the next generation of antibiotics, new therapeutic and diagnostic approaches to lung disease, refining methods for earlier identification of Type II diabetes, studies in the relationship between cardiovascular and kidney diseases, development of enhanced breast cancer detection technology and a novel approach to treating several autoimmune diseases and certain solid tumors.
LA BioMed is an independent research institute that is academically affiliated with the David Geffen School of Medicine at the University of California, Los Angeles. The institute is located on the campus of Harbor-UCLA Medical Center near Torrance. The institute has become an economic engine for the South Bay, pumping an additional $155 million into the local economy in 2005, according to a 2007 Los Angeles Economic Development Corporation report. It contributes to Los Angeles County’s economic viability while inventing the future of health care through its ground-breaking research, its training of the scientists of tomorrow and its service to the local community. Please visit our website at www.LABioMed.org
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JNCI Journal of the National Cancer Institute