"Cholesterol is a vital building block in all cells, and when you take away the building blocks, the cells may stop proliferating," Bojesen explained.
Using the Danish Civil Registration System, a network of national databases, the researchers tracked statin use by individuals over time. They focused on about 296,000 patients who were diagnosed with cancer between 1995 and 2007, with follow-up until the end of 2009.
Patients who had statin prescriptions filled six months to two years before their cancer diagnosis were included in the research. Among those aged 40 or older, almost 19,000 had used statins regularly and about 277,000 had never taken the medications.
Dr. Neil Caporaso, branch chief of the genetic-epidemiology branch at the National Cancer Institute in Bethesda, Md., said he was impressed by the study but also was a bit skeptical.
"What mechanism could extend to every tumor type? We just don't know," said Caporaso, who wrote an accompanying journal editorial.
Many questions must still be answered, he said. "How soon does the effect begin and how long does it last? When is the window [of time] when the response would be expected to be observed?" he said.
In his editorial, Caporaso expressed concern that the research did not reveal what dose would reduce the risk of dying from cancer.
"Although the findings suggest, with a few exceptions, that there were consistent and substantial declines in mortality across diverse cancers, there is no clear pattern of decreased mortality with increased dose," he wrote in the editorial. "All these issues mandate caution in interpreting the findings."
Eric Jacobs, strategic director of pharmacoepidemiology at the American Cancer Society
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