Environmental Factor, November 2007, National Institute of Environmental Health Sciences
Epidemiology Branch Hosts Sister Study Advisory Meeting
By Eddy Ball
More than 43,000 women have joined The Sister Study so far. That was the good news highlighted by investigators and their colleagues in the NIEHS Epidemiology Branch during a September 27 meeting of the study's Scientific Advisory Board held in Rodbell Auditorium. The study has a goal of recruiting 50,000 sisters into its cohort by April 30, 2008.
The Sister Study is a unique long-term study of women aged 35 to 74 whose sisters had breast cancer. With the enormous data that will be available with a large and diverse cohort, the study is an unprecedented effort to understand the relative importance and interplay of genetic and environmental factors in the disease.
The full-day advisory board meeting surveyed progress in the study and examined future directions in data and sample collections, as well as ways to enhance study instruments and recruitment.
Even though enrollment has reached 86% of the initial goal, investigators said they are interested in developing contingency plans in case recruitment slows or the pool of volunteers does not adequately represent a diverse population.
One possible strategy is to continue recruitment efforts beyond the 50,000 goal and leave open the option of extending enrollment of under-represented groups of women - for example, those over 65 or with less than a college education, racial and ethnic minorities and those from specific geographical regions. An alternative is to "filter" enrollment as it approaches the 50,000 subject goal to achieve the desired proportion of priority women. During the meeting, participants heard progress reports by study staff and Epidemiology Branch Chief and Principal Investigator Dale Sandler, Ph.D. Attendees also learned about "Recent Findings in Whole Genome Association Studies" from National Cancer Institute Investigator and Scientific Advisory Board Member Montserrat Garcia-Closas, M.D., Dr.P.H.
NIEHS Biostatistics Branch Chief and Principal Investigator Clarice Weinberg, Ph.D., reported on the "Two-Sister Study." This parallel study, which is focusing on a cohort of 2,000 women, is an investigation of the genetic and environmental causes of young-onset breast cancer.
The meeting concluded with a session on study follow-up planning. Sandler discussed the current biennial follow-up questionnaire and the possible addition of sample collections, such as saliva or buccal cells, to the blood, urine, toenail clippings and dust samples currently collected at baseline. Participants also addressed long-range planning issues for nested studies of genes and gene-environment interactions and specific outcomes, as well as follow-up of participants who develop breast cancer.
The Sister Study Scientific Advisory Board is composed of research scientists and clinicians from NIH institutes, the United States Environmental Protection Agency, universities and organizations from across the country and also includes two community liaisons and representatives from the American Cancer Society, the National Center on Minority Health and Health Disparities, Susan B. Komen for the Cure, the International Cancer Council, Y-Me Breast National Cancer Organization and Sisters Network, Inc.