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Breast Cancer in NE US...

  Don't know if anyone on the list has seen
  this so I thought I'd post it....
  Alex Sagady
  Environmental Consultant
   Office of Cancer
   Building 31,Room
   Bethesda, MD 20892
   National Cancer
               July 15, 1997
              FOR RESPONSE TO
               NCI Press Office
               (301) 496-6641
               New Statistical Methodology Suggests
               Elevated Breast Cancer Mortality in
               Large Parts of Northeastern United
               Using an innovative statistical technique, scientists
               at the National Cancer Institute (NCI) have
               discovered that women living in a broad stretch of
               the metropolitan northeastern United States are
               slightly more likely to die from breast cancer than
               women in other parts of the Northeast. The study
               does not explain why these women are at higher
               risk of death, and the researchers note that the
               increase may be due to geographic differences in
               well-established risk factors for breast cancer
               which they were unable to include in the analysis. 
               "The breast cancer mortality rate along a section
               of the East Coast stretching from New York City
               to Philadelphia is 7.4 percent higher than the rest
               of the Northeast," said Martin Kulldorff, Ph.D.,
               who led the study. "This is a statistically
               significant finding, indicating that elevated risk of
               breast cancer mortality in that area is not a
               random occurrence, but may be due to some
               underlying reason."
               Kulldorff adds that "great caution should be
               exercised in interpreting the study of geographic
               clusters in cancer mortality." In particular,
               ascribing the cause of a mortality cluster to some
               local environmental exposure may be difficult or
               Previous studies have shown that the northeastern
               United States (including CT, DE, MD, ME, MA,
               NH, NJ, NY, PA, RI, VT. and DC) has about a
               16 percent higher breast cancer mortality rate
               than the rest of the country. However, even
               within this region, there is substantial variation.
               Delaware, Massachusetts, New Hampshire, New
               Jersey, New York, Pennsylvania, Rhode Island,
               and Washington DC have higher breast cancer
               mortality rates than the national average. Breast
               cancer mortality rates in four other northeastern
               states -- Maryland, Vermont, Connecticut and
               Maine -- are very close to the national average of
               26.4 per 100,000 women. 
               During the five years (1988-1992) covered by the
               analysis, 24,044 women in the New
               York/Philadelphia region died of breast cancer.
               This was about 200 more deaths per year than
               researchers would have expected to find if this
               area had the same breast cancer mortality rate as
               the rest of the 11-state northeastern region of the
               U.S. The study also showed the existence of four
               smaller clusters of increased mortality within the
               larger New York/Philadelphia area: northeast
               New Jersey, central New Jersey, Philadelphia,
               and Long Island, N.Y.
               Long Island has been a major focus of research
               on breast cancer, following a June 1993
               Congressional mandate to initiate a
               comprehensive study to ascertain whether
               environmental factors might be related to elevated
               breast cancer rates there. In light of this new
               study, Long Island's elevated breast cancer
               mortality rate should be seen as part of a larger
               geographical trend in the New York/Philadelphia
               In the new study, published in the July 15, 1997
               American Journal of Epidemiology, researchers
               used a specially designed computer program that
               places a circular "window" on a map of the 11
               most northeastern states and the District of
               Columbia. They then calculated breast cancer
               mortality rates for the area inside the window's
               circumference and for the remainder of the
               northeastern United States. 
               A newly developed statistical method, called the
               spatial scan statistic, was used to compare these
               two rates. By resizing and moving the window
               across the entire map, the researchers were able
               to systematically scan for possible breast cancer
               mortality clusters and identify approximate
               boundaries for areas where mortality was
               elevated. The moveable window freed
               researchers from having to preselect which states
               or parts of states they would examine. Instead,
               they were able to let the data define the area for
               Researchers also found a higher breast cancer
               mortality rate among women under 50 in the
               District of Columbia, but this cluster was
               explained by its proportionately larger
               African-American population. On average,
               African-American women have a higher mortality
               rate from breast cancer than do white women. In
               a paper published in the Feb. 5, 1997 Journal of
               the National Cancer Institute, NCI epidemiologist
               Robert E. Tarone, Ph.D., reported that breast
               cancer mortality rates for black women in the
               northeastern U.S. are no higher than those for
               black women in other regions. It is thus unlikely
               that widespread environmental exposures explain
               the elevated breast cancer mortality rates among
               white women in the Northeast. 
               The new study found that age, race, urbanization
               and average number of children born could not
               explain the elevated mortality rates for the larger
               New York/Philadelphia region, or for the four
               smaller clusters. However, the researchers could
               not include in their analysis other important risk
               factors for breast cancer such as age at first birth,
               menarche, or menopause, or factors that are
               known to affect mortality, including access to
               health care and regular mammography screening. 
               A study published in the July 2, 1997 Journal of
               the National Cancer Institute demonstrated that
               elevated breast cancer incidence in the San
               Francisco Bay Area could be entirely explained in
               terms of such known risk factors. Results of
               another study led by NCI epidemiologist Susan
               Sturgeon, Dr.P.H., and published in the Dec. 20,
               1995 Journal of the National Cancer Institute
               showed that a large part of the regional
               differences in breast cancer death rates among
               white women in the United States would be
               explained by known factors such as age at first
               birth and mammography screening. 
               In 1997, there will be an estimated 180,200 new
               cases of invasive breast cancer among women in
               the United States, and an estimated 44,190
               women will die from the disease. Breast cancer
               mortality rates vary widely from state to state.
               Hawaii's rate is 32 percent lower than the national
               age-adjusted average of 26.4 per 100,000 women,
               and Washington D.C.'s rate is 28 percent higher.
               The new technique used in the study will help
               researchers overcome a major problem in "cancer
               cluster" investigations: the fact that the areas
               studied as clusters have generally been selected
               based on public concern rather than systematic
               comparison of rates in different areas. 
               NCI, in collaboration with the National Institute of
               Environmental Health Sciences, has undertaken
               two large initiatives to investigate reasons for
               elevated breast cancer death rates in the
               Northeast/Mid-Atlantic regions. These studies are
               being conducted by investigators at major medical
               institutions in the East. Six studies, which
               comprise the Northeast/Mid-Atlantic Study, are
               focusing on organochlorine compounds, which are
               commonly used as pesticides. The Long Island
               Breast Cancer Study Project is investigating
               whether environmental factors are responsible for
               breast cancer risk in Nassau and Suffolk counties.
               This research includes assessments of exposure
               to organochlorines and other chemicals, magnetic
               fields, contaminated drinking water, air pollution,
               and hazardous and municipal waste.
  Alex J. Sagady & Associates        Email:  asagady@sojourn.com
  Environmental Consulting and Database Systems
  PO Box 39  East Lansing, MI  48826-0039  
  (517) 332-6971 (voice); (517) 332-8987 (fax)