Brain Cancer Mortality in the United States

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Brain Cancer Mortalityin the United States

• Joint work with
• Zixing Fang, UCLA
• David Gregorio, Univ Connecticut

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U.S. Brain Cancer Mortality1986-1995
deaths rate (95 CI) Children (age lt20)
5,062 0.75 (0.66-0.83) Adults (age 20)
106,710 6.0 (5.8-6.2) Adult Women
48,650 4.9 (4.7-5.0) Adult Men
58,060 7.2 (7.0-7.5) annual deaths / 100,000
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Brain Cancer

• Known risk factors
• High dose ionizing radiation
• Selected congenital and genetic disorders
• Explains only a small percent of cases.
• Potential risk factors
• N-nitroso compounds?, phenols?, pesticides?,
  polycyclic aromatic hydrocarbons?, organic
  solvents?

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Adjustments
All subsequent analyses where adjusted for

• Age
• Gender
• Ethnicity (African-American, White, Other)

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Brain Cancer Mortality, Children 1986-1995
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Cuzick-Edwards Test Children
k p-value 200 0.04 500 0.13
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Tangos Excess Events TestChildren
l p-value 1000 0.005 2000 0.06
5000 0.21 10000 0.29
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Spatial Scan Statistic, Children
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Children Seven Most Likely Clusters
Cluster Obs Exp RR
p 1. Carolinas 86 51 1.7 0.24 2.
California 16 4.9 3.3 0.74 3. Michigan
318 250 1.3 0.74 4. S Carolina 24 10 2.5 0.79 5
. Kentucky-Tenn 127 88 1.4 0.79 6.
Wisconsin 10 2.4 4.1 0.98 7. Nebraska 12 3.6 3.3
0.99
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Conclusions Children
Some evidence of global spatial clustering, but
rather weak. No statistically significant
clusters detected. Any part of the pattern seen
on the original map may be due to chance.
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How About Adults?
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Brain Cancer Mortality, Adults 1986-1995
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Cuzick-Edwards k-NN All Adults
k p-value 4000 0.0001
10000 0.0001
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Tangos EET All Adults
l p-value 1000 0.0001
2000 0.0001 5000 0.0001 10000 0.0001
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Spatial Scan Statistic Adults
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Brain Cancer Mortality, Adults 1986-1995
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Cuzick-Edwards Women
k p-value 1500 0.0001
3000 0.0001
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Tangos EET Women
l p-value 1000 0.0001
2000 0.0001 5000 0.0001 10000 0.0001
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Spatial Scan Statistic, Women
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Women Most Likely Clusters
Cluster Obs Exp RR
p 1. Arkansas et al. 2830 2328 1.22 0.0001
2. Carolinas 1783 1518 1.17 0.0001 3. Oklahoma
et al. 1709 1496 1.14 0.003 4. Minnesota et
al. 2616 2369 1.10 0.01 10. N.J. /
N.Y. 1809 2300 0.79 0.0001 11. S Texas 127
214 0.59 0.0001 12. New Mexico et al.
849 1049 0.81 0.0001
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Cuzick-Edwards Men
k p-value 2000 0.0001
4000 0.0001
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Tangos EET Men
l p-value 1000 0.0001
2000 0.0001 5000 0.0001 10000 0.0001
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Spatial Scan Statistic Men
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Men Most Likely Clusters
Cluster Obs Exp RR
p 1. Kentucky et al. 3295 2860 1.15 0.0001
2. Carolinas 1925 1658 1.16 0.0001 3. Arkansas
et al. 1143 964 1.19 0.001 4. Washington
et al. 1664 1455 1.14 0.003 5. Michigan 1251 1074
1.17 0.005 11. N.J. / N.Y. 2084 2615 0.80 0.00
01 12. S Texas 157 262 0.60 0.0001 13. New
Mexico et al. 1418 1680 0.84 0.0001 14. Upstate
N.Y. et al. 1642 1895 0.87 0.0001
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Conclusions Adults
Strong evidence of global spatial clustering. It
is possible to pinpoint specific areas with
higher and lower rates that are statistically
significant, and unlikely to be due to
chance. The exact borders of detected clusters
are uncertain. Similar patterns for men and
women.
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Conclusion General
Tests for spatial randomness are very useful
additions to cancer maps, in order to determine
if the observed patterns are likely due to chance
or not. Different tests provide complementary
information.