Declines in Cancer Incidence and Death Rates
A new report from the nation's leading cancer organizations
shows that, for the first time since the report was first
issued in 1998, both incidence and death rates for all cancers
combined are decreasing for both men and women, driven largely
by declines in some of the most common types of cancer. The
report notes that, although the decreases in overall cancer
incidence and death rates are encouraging, large state and
regional differences in lung cancer trends among women underscore
the need to strengthen many state tobacco control programs.
The findings come from the "Annual Report to the Nation
on the Status of Cancer, 1975-2005, Featuring Trends in Lung
Cancer, Tobacco Use and Tobacco Control", online Nov.
25, 2008, and appearing in the Dec. 2, 2008, Journal of the
National Cancer Institute.
Although cancer death rates have been dropping since the
publication of the first Annual Report to the Nation 10 years
ago, the latest edition marks the first time the report has
documented a simultaneous decline in cancer incidence, the
rate at which new cancers are diagnosed, for both men and
women. Based on the long-term incidence trend, rates for all
cancers combined decreased 0.8 percent per year from 1999
through 2005 for both sexes combined; rates decreased 1.8
percent per year from 2001 through 2005 for men and 0.6 percent
per year from 1998 through 2005 for women. The decline in
both incidence and death rates for all cancers combined is
due in large part to declines in the three most common cancers
among men (lung, colon/rectum, and prostate) and the two most
common cancers among women (breast and colon/rectum), combined
with a leveling off of lung cancer death rates among women.
 "The
drop in incidence seen in this year's Annual Report is something
we've been waiting to see for a long time," said Otis
W. Brawley, M.D., chief medical officer of the American Cancer
Society (ACS). "However, we have to be somewhat cautious
about how we interpret it, because changes in incidence can
be caused not only by reductions in risk factors for cancer,
but also by changes in screening practices. Regardless, the
continuing drop in mortality is evidence once again of real
progress made against cancer, reflecting real gains in prevention,
early detection, and treatment."
The new report shows that, from 1996 through 2005, death
rates for all cancers combined decreased for all racial and
ethnic populations and for both men and women, except for
American Indian/Alaska Native men and women, for whom rates
were stable. The drop in death rates has been steeper for
men, who have higher rates, than for women. Death rates declined
for 10 of the top 15 causes of cancer death among both men
and women. However, death rates for certain individual cancers
are increasing, including esophageal cancer for men, pancreatic
cancer for women, and liver cancer for both men and women.
Overall cancer death rates were highest for African-Americans
and lowest for Asian American/Pacific Islanders.
Among men, incidence rates dropped for cancers of the lung,
colon/rectum, oral cavity, and stomach. Prostate cancer incidence
rates decreased by 4.4 percent per year from 2001 through
2005 after increasing by 2.1 percent per year from 1995 to
2001. In contrast, incidence rates increased for cancers of
the liver, kidney, and esophagus, as well as for melanoma
(2003-2005), non-Hodgkin lymphoma, and myeloma. Incidence
rates were stable for cancers of the bladder, pancreas, and
brain/nervous system, and for leukemia.
For women, incidence rates dropped for cancers of the breast,
colon/rectum, uterus, ovary, cervix, and oral cavity but increased
for cancers of the lung, thyroid, pancreas, brain/nervous
system, bladder, and kidney, as well as for leukemia, non-Hodgkin
lymphoma, and melanoma.
"While we have made progress in reducing the burden
of cancer in this country, we must accelerate our efforts,
including making a special effort to reach underserved cancer
patients in the communities where they live," said National
Cancer Institute (NCI) Director John Niederhuber, M.D. "This
report gives us a better understanding of where we may need
to redouble our efforts and try to find new ways of preventing
or reducing the occurrence of kidney, liver, and other cancers
that continue to show increases in both mortality and/or incidence."
The Special Feature section of the Report highlights wide
variations in tobacco smoking patterns across the United States,
which, coupled with differences in smoking behaviors in younger
versus older populations, helps explains the delay in an expected
decrease in lung cancer deaths among women and a slowing of
the decrease in lung cancer deaths among men.
The report finds substantial differences in lung cancer death
rate trends by state and geographic region. For example, lung
cancer death rates dropped an average of 2.8 percent per year
among men in California from 1996 through 2005, more than
twice the drop seen in many states in the Midwest and the
South. The geographic variation is even more extreme among
women, for whom lung cancer death rates increased from 1996
through 2005 in 13 states and decreased only in three. The
report also notes that, in five states (Pennsylvania, Illinois,
Minnesota, Nebraska, and Idaho), lung cancer incidence among
women showed an increasing trend, whereas the mortality trend
was level.
"It's very promising to see the progress we are making
in our fight against cancer," said Centers for Disease
Control and Prevention (CDC) Director Julie Gerberding, M.D.
"Unfortunately, tobacco use continues to plague our country,
and it's the primary reason why lung cancer continues to rob
too many people of a long, productive, and healthy life. We
must recommit ourselves to implementing tobacco control programs
that we know work if we are truly going to impact the staggering
toll of tobacco on our society."
Variation in smoking prevalence among the states is influenced
by several factors, including public awareness of the harms
of tobacco use, social acceptance of tobacco use, local tobacco
control activities, and tobacco industry promotional activities
targeted in a geographic area. The 13 states where lung cancer
death rates for women are on the rise have higher percentages
of adult female smokers, low excise taxes, and local economies
that are traditionally dependent on tobacco farming and production.
In contrast, California, which was the first state to implement
a comprehensive, statewide tobacco control program, was the
only state in the country to show declines in both lung cancer
incidence and deaths in women.
According to a U.S. Surgeon General's report, cigarette smoking
accounts for approximately 30 percent of all cancer deaths,
with lung cancer accounting for 80 percent of the smoking-attributable
cancer deaths. Other cancers caused by smoking include cancers
of the oral cavity, pharynx, larynx, esophagus, stomach, bladder,
pancreas, liver, kidney, and uterine cervix and myeloid leukemia.
"We can see that, in areas of the country where smoking
and tobacco use are entrenched in daily life, men and women
continue to pay a price with higher incidence and death rates
from many types of cancer. This type of geographic variation
in smoking-related cancers is due to smoking behaviors, not
regional environmental factors," said Betsy A. Kohler,
M.P.H., executive director of the North American Association
of Central Cancer Registries (NAACCR).
"The observed decrease in the incidence and death rates
from all cancers combined in men and women overall and in
nearly all racial and ethnic groups is highly encouraging,"
conclude the authors. "However, this must be seen as
a starting point rather than a destination." They say
a dual effort, combining better application of existing knowledge
with ongoing research to improve prevention, early detection,
and treatment will be needed to sustain and extend this progress
into the future.
The study was conducted by scientists at the ACS, CDC, NCI,
which is part of the National Institutes of Health, and the
NAACCR.
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