Does Inflammation Predict Colon Cancer?
February 18, 2004
A study conducted over an 11-year period showed that people
with higher levels of C-reactive protein (CRP) in their blood
were more likely to develop colorectal cancers than those
with low levels of CRP. CRP is a marker of inflammation circulating
in the blood. Higher levels of CRP are already associated
with chronic diseases such as heart disease, stroke, diabetes
and, now, colon cancer.
Researchers studied records of almost 23,000 adults who had
participated in a study that started between May and October
1989, looking to identify those who developed colon or rectal
cancer. At the time the study was conducted, the participants
provided blood samples and completed questionnaires. Since
then, the participants have been given additional questionnaires
and tracking data.
Researchers found 172 participants who drew blood, up until
December 2000, were diagnosed with either colon or rectal
cancer. Of those, 131 had colon cancer and 41 had rectal cancer.
They also noted that medium levels of CRP were higher among
people who had developed colon cancer than among those who
remained healthy and disease free.
However, by contrast, CRP levels were not significantly different
between patients who developed rectal cancer than those who
remained disease free.
As stated in the article, the study also found that:
The odds of developing colorectal cancers increased progressively
with higher concentrations of CRP. Overall, people in
the highest fourth of CRP had twice the risk of developing
colorectal cancer, and 2.5 times the risk of developing
colon cancer, as those in the lowest fourth.
Among nonsmokers, those in the highest fourth of CRP
were 2.5 times as likely to develop colorectal cancer,
and 3.5 times as likely to develop colon cancer, as those
in the lowest fourth.
Those who had taken either aspirin or nonsteroidal anti-inflammatory agents
within the 48 hours prior to blood draw had a reduced
risk of colorectal cancer.
The association of inflammation with colon cancer was unrelated to diabetes,
going against the belief that diabetes acts as the mediator
between inflammation and cancer risk.
Researchers believe the link between chronic inflammation
and colon cancer must be further explored before C-reactive
protein is confirmed as a risk predictor.
EurekAlert! February 3,