RESEARCH TRIANGLE PARK, North Carolina—Researchers have begun the first phase of a long-term, prospective epidemiological study designed to determine the role of genetic, environmental, and lifestyle factors in increasing the risk of breast cancer and several other diseases. The Sister Study is the first long-term follow-up study specifically designed to look at hereditary and environmental risk factors for the disease. It seeks to enroll 50,000 cancer-free women in the United States between the ages of 35 and 74 who have a sister diagnosed with breast cancer.
"Our overall goal is to create a framework from which we, and others who might collaborate with us, can ask questions about the role of the external environment, which has not been studied very well in breast cancer risk," said co-principal investigator Dale Sandler, PhD.
Dr. Sandler is the acting chief of the Epidemiology Branch at the National Institute of Environmental Health Sciences (NIEHS). The institute is funding the project, which is expected to cost about $7 million a year. Clarice Weinberg, PhD, chief of NIEHS’s Biostatistics Branch, is the other co-principal investigator.
"The Sister Study is unique among cohort studies in the emphasis we have put on external environmental exposures," Dr. Sandler said. "The current cohort studies— the Nurses’ Health Study and others— really focus on lifestyle. In the Sister Study, we are trying to address this other piece of the puzzle, the environment."
Researchers began recruiting for the study in Tampa, Florida, in September and have expanded their efforts to Phoenix, Arizona; St. Louis, Missouri; and Providence, Rhode Island, all chosen for the initial phase of the study because of their size and geographic, ethnic, and socioeconomic diversity.
The target enrollment for the four cities is 2,000 women over 6 to 9 months. Using the experience they gain from enrolling women from the initial four cities, the research team will refine its recruiting strategies and launch a national enrollment effort in the summer of 2003.
Dr. Sandler and her colleagues have enlisted breast cancer advocates and other groups to aid in enrollment. The initial recruitment effort took place during the Tampa Bay area Race for the Cure. "We have built a list of volunteers who are connected with different organizations throughout the United States, who have agreed to help us recruit women," Dr. Sandler said.
