Changing Epidemiology of Colorectal Cancer in Minnesota – Minnesota Department of Health
Background
Colorectal cancer kills more Minnesotans than either breast
or prostate cancer. Screening can reduce
the incidence of colorectal cancer by finding and removing polyps before they
become malignant, and can further reduce mortality by finding malignant lesions
at an early, treatable stage. It is estimated that at least one third of
colorectal cancer deaths could be prevented through regular screening of
average risk adults age 50 and older.
Methods
This study uses data from the Minnesota Cancer Surveillance System
(MCSS) to examine urban and rural trends in colorectal cancer incidence since
1988 and race-specific rates aggregated over the five-year period 2000-2004. Behavioral Risk Factor Surveillance System
(BRFSS) data were used to examine self-reported screening behavior of
Minnesotans ages 50 and older by education and urban/rural residence.
Results
In 1988, when cancer became a reportable disease in Minnesota, residents of
urban and rural areas of the state were equally likely to be diagnosed with colorectal
cancer. The age-adjusted rate was 66.7
new cases per 100,000 persons in the 18 counties considered as part of the metropolitan
area in the 2000 Census and 67.6 elsewhere in the state. Since then, the risk
of being diagnosed with this common cancer has declined significantly in both
rural and urban Minnesota.
However, the rate has declined more than twice as fast in urban areas, so that
in 2003, the risk of being diagnosed with colorectal cancer was 25 percent
higher in rural (60.4 per 100,000) than urban (47.3) Minnesota. Incidence rates for 2004 will be
presented. American Indians have the highest colorectal cancer incidence and
mortality rates in Minnesota,
while nationally they have among the lowest.
In 2004, 66 percent of screening-eligible Minnesotans
reported having had at least one sigmoidoscopy or colonoscopy compared to a
median of 53 percent in the 52 states and territories participating in the
survey. Since 2000, about 60 percent of Minnesotans ages 50 and older reported
having had a sigmoidoscopy or colonoscopy in the last five years or having had
a fecal occult blood test in the last year. Screening-eligible adults who were
“up-to-date” for colorectal cancer screening according to these criteria were
about the same for men (61%) and women (62%). However, rural Minnesotans were
less likely to report being up-to-date (57%) than urban residents (64%), and
rural residents with less than a high school education were the least likely to
be screened (47%). Too few American
Indian Minnesotans were interviewed to examine screening prevalence in this
group.
Conclusions
Although other factors may be involved, a recent change to a
higher rate of colorectal cancer in rural compared to urban Minnesota
is consistent with lower self-reported screening, and indicates that
interventions to increase screening in rural Minnesota are merited. In addition,
exceptionally high rates of colorectal cancer among American Indians in Minnesota indicate that
increased colorectal cancer screening in this group could save lives.
For more information, contact: Carin
Perkins
Phone: 651-201-5906
Email: carin.perkins@health.state.mn.us
Obj 23
Rev 05-23-07
|
