Tom Murphy
Newswire21.org

Men with lower cholesterol levels are less likely to develop the deadliest form of prostate cancer, according to a study of 5,586 men funded by the National Cancer Institute.

Researchers at Johns Hopkins Kimmel Cancer Center found a 59 percent reduction in so-called "high-grade" prostate cancer, an aggressive form of the disease with a poor prognosis.

Total cholesterol levels over 200 mg/dL have long been associated with increased rates of heart disease, and use of cholesterol-lowering statin drugs were previously linked to lower rates of advanced prostate cancer.

"For many reasons, we know that it's good to have a cholesterol level within the normal range," said Dr. Elizabeth Platz, co-director of the cancer program at the center. "Now, we have more evidence that among the benefits of low cholesterol may be a lower risk for potentially deadly prostate cancers."

To be sure, Platz said more testing is needed before doctors would try to prevent or treat the disease by targeting cholesterol levels.

Platz was among those who found similar results in a separate study last year. She also led the team that linked statins to lower rates of prostate disease.

In this study, Platz and her team collaborated with the Southwest Oncology Group to study men over 55 who were enrolled in the Prostate Cancer Prevention Trial from 1993 to 1996. Some 1,251 men were diagnosed with prostate cancer during the study.

Almost three out of five men with cholesterol levels under 200 avoided the high-grade cancers that spread more rapidly, which are identified by a Gleason score of between eight and 10. 

Although the higher rate of serious cancers were tied to cholesterol, the was no significant correlation of the overall incidence of prostate cancer to high cholesterol.

Outside Factors
Platz warned that outside factors could have affected the results, although the study controlled for such factors as smoking, weight, family history and dietary cholesterol.  One example was whether the men were taking drugs at the time of blood collections that might affect cholesterol levels - a factor researchers hope to analyze soon.

The report was published in the journal Cancer Epidemiology, Biomarkers & Prevention. A second report from the National Cancer Institute showed lower cholesterol in men was linked to 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," said Platz. "Cancer cells use these survival pathways to evade the normal cycle of cell life and death."