Low Cholesterol May Reduce Risk For High-grade Prostate Cancer
Men with lower cholesterol are
less likely than those with higher levels to develop high-grade
prostate cancer, an aggressive form of the disease with a
poorer prognosis, according to results of an important
Johns Hopkins collaborative study.
In a prospective study of more than 5,000 U.S. men, epidemiologists
say they now have evidence that having lower levels of heart-clogging
fat may cut a man's risk of this form of cancer by nearly 60 percent.
"For many reasons, we know that it's good to have a cholesterol level
within the normal range. Now, we have more evidence that among
the benefits of low cholesterol may be a lower risk for potentially
deadly prostate cancers." reported the researchers.
As a reference, the normal range is defined as less than 200 mg/dL
(milligrams per deciliter of blood) of total cholesterol.
The researchers found similar results in a study first published in
2008, and in 2006, they linked use of cholesterol-lowering statin
drugs to lower risk of advanced prostate cancer.
For the current study, researchers from the Southwest Oncology
Group and other collaborators analyzed data from 5,586 men aged
55 and older enrolled in the Prostate Cancer Prevention Trial from
1993 to 1996. Some 1,251 men were diagnosed with prostate cancer during the study period.
Men with cholesterol levels lower than 200 mg/dL had a 59 percent
lower risk of developing high-grade prostate cancers, which tend to
grow and spread rapidly. High-grade cancers are identified by a
pathological ranking called the Gleason score. Scores at the highest
end of the scale, between eight and 10, indicate cancers considered
the most worrisome to pathologists who examine samples of the
diseased prostate under the microscope.
In this new study, cholesterol levels had no significant effect on the
entire spectrum of prostate cancer incidence, only those that were
While the team took into account factors that could bias the results,
such as smoking history, weight, family history of prostate cancer,
and dietary cholesterol, other things could have affected their results.
One example is whether men in the study were taking cholesterol-
lowering drugs at the time of the blood collections, a data point the
researchers expect to analyze soon.
Results of the current study are expected to be published online
this month in the Journal Cancer Epidemiology, Biomarkers &
Prevention. Also in the journal is an accompanying paper from
the National Cancer Institute showing that lower cholesterol in
men conferred a 15 percent decrease in overall cancer cases.
"Cholesterol may affect cancer cells at a level where it influences key
signaling pathways controlling cell survival. Cancer cells use these
survival pathways to evade the normal cycle of cell life and death."
explained the researchers.
Targeting cholesterol metabolism may be one route to treating and
preventing the disease, but this remains to be tested.
Funding for the study was provided by the National Cancer Institute