Sandy Hutchens Cancer Prevention

Men with low cholesterol levels have a decreased risk of high-grade prostate cancer..

A study, including almost 5,600 men aged 55 years and over randomized to the placebo section of the Prostate Cancer Prevention Trial (PCPT), showed that men whose cholesterol levels were below 200 mg/dL had a 60% decreased risk of Gleason 8 to 10 prostate cancer compared with men who had higher cholesterol levels, researchers reported in Cancer Epidemiology, Biomarkers & Prevention. Clinicians diagnosed prostate cancer in 1,251 men (22%).

The investigators, led by Elizabeth A. Platz, ScD, MPH, of Johns Hopkins Bloomberg School of Public Health in Baltimore, found no association between cholesterol levels and prostate cancer overall.

“Our findings add to the literature supporting a role for cholesterol in the etiology of prostate cancer with a worse prognosis,” the authors wrote.

The PCPT, which started in 1993, investigated whether finasteride could prevent prostate cancer. Researchers randomized subjects to receive 5 mg/day of finasteride or placebo for seven years. The study showed that finasteride treatment was associated with a 25% decreased incidence of prostate cancer.

In contrast to their findings in the placebo arm of the trial, Dr. Platz and her collaborators observed no association between serum cholesterol and high-grade prostate cancer in the finasteride arm. The researchers said the pattern they observed in the placebo arm, in theory, could be explained by a lower sensitivity for detecting high-grade prostate cancer in the men with low rather than high cholesterol, “but this is not the expectation.” Men with low cholesterol, the group explained, on average have a lower prostate volume. Thus a greater proportion of the total prostate could be sampled by needle biopsy, increasing the sensitivity of detecting high-grade tumors. Another explanation, they noted, is that finasteride prevented the same subset of high-grade cancers that low cholesterol would have prevented. It also is possible that the accuracy in detecting high-grade cancers differed in men with low cholesterol in the placebo arm compared with the finasteride arm.

A prostate cancer researcher not involved with the new study, Stephen J. Freedland, MD, of the Duke Prostate Center at Duke University Medical Center in Durham, N.C., said the study by Dr. Platz’s team is consistent with previous research and “provides some of the strongest data to date” linking high cholesterol with an increased risk of high-grade prostate cancer.

Dr. Freedland said he has started to mention this association to men with high cholesterol when counseling them about whether to go for PSA testing. “I say to patients, ‘There are increasing data to suggest that high cholesterol may increase your risk of aggressive prostate cancer.’”

As for whether a man should be placed on a statin to reduce his risk of aggressive prostate cancer, Dr. Freedland observed, “If he has high cholesterol, he should probably be on a statin anyway.” It is unknown whether statin treatment would further reduce the risk in men with low cholesterol, he said.

Previous studies suggest that statin use may protect against advanced prostate cancer. For example, a study published in the Journal of the National Cancer Institute (2006;98:1819-1825) showed that statin use was associated with a 43% decreased risk of advanced prostate cancer and a 65% decreased risk of fatal or metastatic prostate cancer.

Recently, researchers reported on a study involving 1,351 prostate cancer patients who underwent radical prostatectomy (504 who used statins and 847 who did not). Preoperative PSA levels, tumor volume, and percentage of cancer in the surgical specimen were significantly lower in the statin users, who overall had a proportionately lower rate of adverse tumor pathology features, including a significantly reduced risk of positive surgical margins, researchers reported in BJU International (2009; published online ahead of print).

Dr. Freedland—whose research has focused on risk factors for prostate cancer and its recurrence following treatment, as well as on prostate cancer chemoprevention—said it is biologically plausible for cholesterol to be involved in the pathogenesis of high-grade prostate cancer. Cholesterol is the precursor for testosterone, which promotes prostate tumor growth, Dr. Freedland said. Hypothetically, high cholesterol concentrations could mean greater testosterone production, he said. Evidence is mounting that high-grade, castration-resistant tumors can make their own testosterone from cholesterol, he noted.

Cholesterol also may directly stimulate tumor growth, he explained. In addition, all new cells need cholesterol as part of their membranes. “Thus, lower cholesterol means it is harder for the cells to replicate,” he said. “Given that high-grade tumors grow faster, this could explain why low cholesterol only reduced the risk of high-grade disease. All of these mechanisms suggest that it is indeed plausible that high cholesterol could promote more aggressive cancers.”

From the November 2009 Issue of Renal And Urology News

Cholesterol: What Your Doctor Didn’t Tell You

Sandy Hutchens loves a fresh brewed cup of green tea.

Although scientists are reluctant to endorse green tea as a cancer prevention method, evidence continues to grow regarding the chemically complex drink’s potential benefits – including results of a new randomized, controlled trial by researchers at University of Texas M. D. Anderson Cancer Center, which suggest it had some inhibiting effect in patients with a pre-malignant condition known as oral leukoplakia.

As reported in a report published online Nov 5 by Cancer Prevention Research(1), a team headed by Vassiliki Papadimitrakopoulo, MD, professor of medicine in M.D. Anderson’s Department of Thoracic/Head and Neck Medical Oncology, tested green tea extract taken orally for three months by 41 patients diagnosed with oral leukoplakia and therefore at high risk of developing oral cancer.

The patients were divided into cohorts taking either placebo or one of three different doses of green tea extract 500 mg/m2, 750 mg/m2 or 1,000 mg/m2 [mg/m2 refers to milligrams per meter squared of body mass – calculated by a formula using height and weight to reflect a person’s relative size].

The researchers assessed clinical response in oral pre-malignant lesions and found:

• 58.8% of patients at the highest doses displayed clinical response,

• Compared with 18.2% among those taking placebo.

They also observed:

• A trend toward improved histology [cell & tissue integrity],

• And a trend towards improvement in a handful of biomarkers that may be important in predicting cancer development.

Patients were followed for 27.5 months and at the end of the study period, 15 developed oral cancer.

• Although there was no difference in oral cancer development overall between those who took green tea and those who did not,

• Patients who presented with mild to moderate dysplasia [abnormal cell growth] had a longer time to develop oral cancer if they took green tea extract.

Although encouraged by the results, Dr. Papadimitrakopoulo cautioned against any recommendations that green tea could definitely prevent cancer.

“This is a phase II study with a very limited number of patients who took what would be the equivalent of drinking eight to 10 cups of green tea every single day,” she said. “We cannot with certainty claim prevention benefits from a trial this size.”

Dong Shin, MD, (professor of hematology and medical oncology at Emory School of Medicine, and a Cancer Prevention Research editorial board member) agreed, but said this trial is certainly a step in the right direction. “A clinical trial with a natural compound is no easy task, and these researchers have accomplished that,” Dr. Shin stated in a companion article commenting on the trial(2). “The lack of toxicity is also important because often when you give supplements at higher doses than what would occur naturally, you induce nausea and vomiting. That did not happen in this trial.”

Neither researcher had a reason why patients concerned about cancer should not drink green tea, but they cautioned against relying on the beverage to definitively reduce their risk of cancer.

“The goal of this kind of research is to determine whether or not these supplements have long-term prevention effects,” said Dr. Papadimitrakopoulou. “More research – including studies in which individuals at high risk are exposed to these supplements for longer time period – is still needed to answer that sort of question.”

Sandy Hutchens Cancer Prevention – Researchers from McGill University in Montreal surveyed nearly 3,600 Canadian men aged 35 to 70 and found those who averaged at least a drink a day had higher risks of a number of cancers than men who drank occasionally or not at all.

These included cancers of the esophagus, stomach, colon, lungs, pancreas, liver and prostate.

When the researchers looked at individual types of alcohol, though, only beer and “spirits” — and not wine — were linked to elevated cancer risks.

In general, the odds increased in tandem with the men’s lifetime alcohol intake, according to findings published in the Cancer Prevention and Detection. With several cancers, men who drank at least once a day tended to have higher risks than those who drank on a regular, but less-than-daily, basis.

When it came to esophageal cancer, for instance, men who had a drink one to six times per week had an 83 per cent higher risk than teetotalers and less-frequent drinkers, while daily drinkers had a three-fold higher risk.

In addition, when the researchers looked only at daily drinkers, the risks generally increased with the number of years the men had been drinking daily.

“Our results show that the heaviest consumers over the lifetime had the biggest increases in the risks of multiple sites of cancer,” researcher Dr. Andrea Benedetti told Reuters.

Many studies have suggested that moderate drinking — usually defined as no more than a drink or two per day — can be a healthy habit, particularly when it comes to heart disease risk.

But the current study suggested that even such moderate drinking levels are linked to higher risks of certain cancers, at least when the alcohol of choice is beer or liquor.

The question of whether moderate drinkers should cut down, however, cannot be answered by a single study.

The Science Behind Beer and Health
October 2006 (Medialink) – Who knew that beer may help reduce the risk of heart disease and certain other chronic diseases related to aging? According to a professor of medicine and public health at the Boston University School of Medicine, it may. Dr. Curtis Ellison spoke at a conference on a panel called, “Beer: To Your Health!,” held by the Center for Food, Nutrition and Agriculture Policy at the University of Maryland-College Park. This conference reviewed the science on health benefits of moderate beer and alcohol consumption and the challenges of communicating a balanced message to the public.

Brewed from barley, malt and other grains, some studies suggest that beer may have heart-healthy benefits and that older adults who consume moderate amounts of alcohol may have a lower risk of heart disease, stroke, diabetes, dementia, osteoporosis – and maybe even obesity.

The key is moderation. U.S. dietary guidelines define “moderation” as one drink per day for women, and two for men. Experts say that for those who choose to drink, alcohol should be consumed with food – and that the total number of alcoholic drinks should not be averaged out for the week. That means people should not save their ‘drink a day’ all week and then have seven drinks on Saturday night.