Overview of the Long Island Breast Cancer Study Project

In the early 1990s, breast cancer advocates asked their U.S. Congressional representatives for an investigation of the high rates of breast cancer in Nassau and Suffolk counties (Long Island), in the State of New York. In 1993, Public Law 103.43 was passed, which mandated that the National Cancer Institute (NCI), in partnership with the National Institute of Environmental Health Sciences (NIEHS), undertake the investigation of breast cancer on Long Island and in Schoharie County, N.Y., and Tolland County, Conn. - two counties which at one time had the highest age-adjusted morality rates of breast cancer. The Public Law also called for the development of a geographic information system (GIS). A GIS is a powerful software application that permits layers of geospatial information like breast cancer rates and environmental exposures to be viewed simultaneously.

The resulting law led to the creation of the Long Island Breast Cancer Study Project (LIBCSP), which encompassed a multi-study effort to investigate whether environmental factors are responsible for breast cancer in the four counties. It also led to the development of the Geographic Information System for Breast Cancer Studies on Long Island (LI GIS). More than ten studies have been conducted, including human population (epidemiologic) studies, the establishment of a family breast and ovarian cancer registry, and laboratory research on mechanisms of action and susceptibility in the development of breast cancer. Most of the studies were conducted by scientists at major medical research institutions in the Northeast, and most of the studies are completed and the findings reported in peer-reviewed journals. Data from the centerpiece case-controlled study "Breast Cancer and the Environment on Long Island" and the follow-up study of women with breast cancer who participated in the initial study continue to be analyzed and published. For more information on the study results from the LIBCSP, please see the information listed on NCI's Epidemiology and Genetics Research web site.

Among the findings, the completed investigations:

Demonstrated that organochlorine compounds (e.g. pesticides including DDT/DDE, dieldrin, chlordane, and polychlorinated biphenyls (PCBs)) are not associated with increased risk for breast cancer on Long Island;
Found that polycyclic aromatic hydrocarbons (PAHs) were associated with a modest increased risk for breast cancer, which will need to be confirmed in studies of other populations;
Found that PCBs may be associated with an increased risk for reoccurrence of breast cancer, which is being investigated further (numbers were small and no association had been seen with initial diagnosis of cancer);
Demonstrated that electromagnetic fields (EMFs) are not associated with increased risk for breast cancer on Long Island;
Confirmed the presence of established risk factors for breast cancer among women; and
Developed new and improved research methods to advance epidemiologic investigations.

The LIBCSP has been a complex research effort that has charted new ground in environmental epidemiology. The assessment of environmental exposures and determing their relationship with cancer has proven difficult, but new studies and progress in the field of breast cancer research continue to be ongoing.

New Direction for Research on Breast Cancer and the Environment

Separate from the LIBCSP, a new generation of research on breast cancer and the environment now is underway. The NIEHS and NCI are funding four Breast Cancer and the Environment Research Centers (BCERC) to study the prenatal-to-adult environmental exposures that predispose females to breast cancer. In 2003, grants totaling 5 million a year over 7 years, or 35 million, were awarded to the centers.

The centers are working collaboratively on two main fronts. Using animals, they are studying the development of mammary tissue and the effects of specific environmental agents. In the second collaborative project, they are enrolling different ethnic groups of young girls and studying their life exposures to a wide variety of environmental, nutritional, hormonal, and social factors that impact puberty. Early puberty has been shown to increase breast cancer risk later in life. For information on this current study please visit the BCERC web site. Also, see an article in the NCI Cancer Bulletin about BCERCs (August 15, 2006).