[ RadSafe ] Radiation exposure poses similar risk of first and second cancers in atomic bomb survivors
royherren2005 at yahoo.com
Wed Sep 15 00:44:50 CDT 2010
Public release date: 15-Sep-2010
Contact: Kristen Woodward
kwoodwar at fhcrc.org
Fred Hutchinson Cancer Research Center
Radiation exposure poses similar risk of first and second cancers in atomic bomb
First large-scale study to assess how radiation influences risk of multiple
SEATTLE – It is well known that exposure to radiation has multiple harmful
effects – including causing cancer – but until now, it has been unclear to what
extent such exposure increases a person's risk of developing more than one
The first large-scale study of the relationship between radiation dose and risk
of multiple cancers among atomic bomb survivors in Hiroshima and Nagasaki, Japan
reveals a similar risk in the development of first and second subsequent
Christopher I. Li, M.D., Ph.D., and colleagues at Fred Hutchinson Cancer
Research Center led the study in collaboration with investigators at the
Radiation Effects Research Foundation in Hiroshima and Nagasaki and the National
Cancer Institute. The results appear in the Sept. 15 issue of Cancer Research.
"We found that radiation exposure increased the risks of first and second
cancers to a similar degree," said first author Li, a breast cancer
epidemiologist and member of the Public Health Sciences Division at the
Hutchinson Center. "People exposed to radiation who developed cancer also had a
high risk of developing a second cancer, and the risk was similar for both solid
tumors and leukemias in both men and women, regardless of age at exposure or
duration between first and second primary cancers," he said.
The association between radiation exposure and risk of second cancers was
particularly significant for radiation-sensitive cancers, such as those of the
lung, colon, breast, thyroid and bladder, as well as leukemia.
For the study, the researchers analyzed data from participants in the Life Span
Study, a group of atomic bomb survivors in Hiroshima and Nagasaki who were
followed from 1950, five years after the bombings, to 2002, the most recent year
through which Hiroshima and Nagasaki cancer registry data were complete. The
study followed 10,031 primary cancer survivors, among whom 1,088 went on to
develop second primary cancers.
Stomach, lung, liver and female breast cancers were the most commonly diagnosed
first and second primary cancers.
"Our findings suggest that cancer survivors with a history of radiation exposure
should continue to be carefully monitored for second cancers," Li said.
In addition to clinical implications for cancer patients and others exposed to
significant amounts of radiation, such research is essential to developing
radiation protection limits and standards for occupational exposures, as well as
planning for the consequences of widespread radiation exposure in the general
population in the event of a nuclear accident, nuclear war or "dirty bomb"
"We greatly appreciate having the opportunity to conduct this unique research
with our Japanese colleagues who, through innumerable publications, have truly
transformed the tragedy of the atomic bombings to fundamental scientific
advancements that have impacted radiation protection standards and policies
worldwide," Li said.
The Radiation Effects Research Foundation (RERF) in Japan is a private,
nonprofit foundation funded by the Japanese Ministry of Health, Labour and
Welfare and the U.S. Department of Energy through the National Academy of
Sciences. RERF funded this research along with the National Cancer Institute and
the National Institutes of Health Division of Cancer Epidemiology and Genetics.
At Fred Hutchinson Cancer Research Center, our interdisciplinary teams of
world-renowned scientists and humanitarians work together to prevent, diagnose
and treat cancer, HIV/AIDS and other diseases. Our researchers, including three
Nobel laureates, bring a relentless pursuit and passion for health, knowledge
and hope to their work and to the world. www.fhcrc.org
More information about the RadSafe