"A Meta-Analysis of Cancer Incidence in United States and
Canadian Native Populations."
International Journal of Epidemiology, Vol 20, #2,
pp. 323-327, 1991.
AUTHORS
Martin C. Mahoney
School of Public Health
State University of New York at Albany
Arthur M. Michalek
Roswell Park Graduate Division
State University of New York at Buffalo
ABSTRACT
""A meta-analytic approach was used to summarize studies of
cancer incidence among Native populations in the United States
and Canada. Native males and females were found to have a
significantly lower incidence of cancer for all sites combined.
Among Native males, kidney cancer was found to exhibit signifi-
cantly elevated incidence, while significantly lower incidence
was found for cancers of the colon, lung, and prostate, and for
lymphomas and leukaemias. Native females were found to have
significantly elevated incidence for cancers of the gall-
bladder, cervix, and kidney, while significantly decreased
incidence was found for cancers of the colon, breast and uterus
and for lymphomas. The use of meta-analysis to integrate the
findings from these studies allowed the identification of
subtle differences in cancer incidence. Although these
findings are not definitive, they overcome the limited numbers
of site-specific cancers reported in many previous studies and
are suggestive of general patterns of cancer incidence among
Native populations. In addition, these results may be useful
in indicating directions for future research involving specific
cancer sites with elevated incidence."
>From the Discussion:
"Factors in the etiology of kidney cancer have been identified,
including cigarette smoking, occupational exposure, and
obesity. The observation of elevated kidney cancer incidence
among both Native males and females is noteworthy and warrants
further exploration. Although smoking is the most important
risk factor for kidney cancer, lung cancer incidence among
Native males and females was found to be significantly
decreased, suggesting that increased kidney cancer incidence
among Natives is due to some factor(s) other than smoking."
"The elevated risk of cervical cancer noted in this analysis
indicates the need for continued promotion of cervical
screening programs among Native populations."
"Several explanations may be advanced to account for the lower
overall cancer incidence rates observed among Native popu-
lations. The most probable is competing causes .... It is
possible that Natives who might have gone on to develop cancer
may have succumbed to death from causes such as accidents,
diabetes, infectious diseases, and other competing causes of
death."
Mary Firestone (617) 482-9485
JSI Center for Environmental Health Studies
Boston EcoNet:mfirestone