Howard Waage ---- Editor
Where: Our meeting will be in the Bennett & Suzy Katz Cancer Resource Center on the 1st Floor of the two-story redwood Education Building behind Santa Cruz Dominican Hospital.
When: Tuesday, January 26th, 2010 7:00 PM. For more information: Please call-The Bennett and Suzy Katz Cancer Resource Center at Dominican Hospital (831) 462-7770
Please feel free to contact any of the following steering committee members if you would like to volunteer or if you have any suggestions or questions.
- Joe Ferrara 426-7724 - - Frank and Janet Schmetz 438-4781 - - Bill McDermott 423-8350 - - Howard Waage 688-0423 -- Julie Batz 724-2701 - Ron Locey 214-4338 - - Ed Avona 685-9106
The subject of prostate cancer screening continues to draw media attention. Dr. Catalona believes the coverage is confusing men who are making decisions about PSA screening and early detection for prostate cancer. His concern is that men, whose lives could be saved by early diagnosis and treatment for prostate cancer, will now find false justification for not screening. He will continue to present his rationale for the life-saving benefits of PSA screening, early detection, and early treatment.
I continue to recommend PSA screening to my patients. PSA testing provides the best estimate of risk for having prostate cancer and the greatest chance of avoiding death from this disease.PSA screening has been widely accepted in the United States and many other countries because it works.
Patients and physicians who are concerned about decreasing the death rate from prostate cancer have relied upon the test because it gives them valuable information and because death rates have continued to fall during the PSA era. Although the PSA test is not perfect, it is effective in identifying men at high risk for prostate cancer and for detecting it early. Moreover, a strong correlation exists between PSA and aggressive forms of the disease. During the PSA screening era in the U.S., there has been an 85% decrease in the percentage of prostate cancer cases that present with advanced-stage disease and a 40% reduction in the age-specific prostate cancer mortality rate. Similar trends have been reported from the World Health Organization Database in countries that have adopted PSA screening but not in those that have not. These impressive trends would not have occurred if screening detected only harmless cancers.
Screening Makes Treatment More Effective - Early detection would be useless without effective treatment. The most effective curative treatment, radical prostatectomy, was available before the PSA era, but this treatment didn't show falling death rates until PSA testing was implemented.
Curative treatments are effective mainly in patients with early disease, which is why the most important factor responsible for the falling death rates is PSA screening. Dr. Catalona's research group participates in large prostate cancer screening events whenever possible. The physician's job is to ensure that patients receive effective, high-quality treatment to maximize cure rates and minimize side effects.
The goal of screening is to detect cancers that could cause suffering and death, but screening may also detect cancers that would never cause symptoms. Currently, because of limited ability to distinguish between harmless and lethal cancers, most cancers are treated.
Over-diagnosis Is Minimal and Inevitable - Some “over-diagnosis” and “overtreatment” will occur with early detection screening, but research on my 5,000+ patients shows it is minimal compared to the “underdiagnosis” of prostate cancer. To date, no validated test is superior to PSA as a screening device. There is always hope that the PSA test, itself, may be further refined or some other test discovered that would be even more precise. The intelligent use of such tests could certainly diminish, but never completely eliminate, some over-diagnosis and over-treatment.
Presently, no one is able to predict the aggressive or non-aggressive traits of diagnosed prostate cancer. Which patients or doctors would choose to play a game of Russian roulette with the diagnosis of prostate cancer when so many men die from it? “Under-diagnosis” and “under-treatment” are important concerns that have received much less attention than “overdiagnosis” even though they have life-threatening consequences.
“Under-diagnosis” and “under-treatment” occur when prostate cancer is not detected until it has spread beyond the prostate and when that unnecessary delay in treatment prevents a cure that would have been the result of earlier treatment. Research on my 5,000+ patients shows “underdiagnosis” is more of a concern than “over-diagnosis.”
Active surveillance and focal therapy have emerged as strategies to guard against over-treatment; however, physicians should be careful not to throw out the baby with the bath water. With active surveillance (also known as “watchful waiting”) or focal therapy (also known as “the male lumpectomy”), potentially life-saving treatment may be delayed in patients with initially under-graded or understaged tumors. Some will slip through the cracks and have unnecessary suffering and death from prostate cancer.
As little as 15 minutes of exercise a day can reduce overall mortality rates in patients with prostate cancer, according to findings presented at the American Association for Cancer Research Frontiers in Cancer Prevention Research Conference, Dec. 6-9, 2009.
"We saw benefits at very attainable levels of activity," said Stacey A. Kenfield, Sc.D., epidemiology research associate at the Harvard School of Public Health and lead author of the study. "The results suggest that men with prostate cancer should do some physical activity for their overall health."
Researchers assessed physical activity levels for 2,686 patients enrolled in the Health Professionals Follow-up Study, both before and after diagnosis (men with metastases at diagnosis were excluded).
Men who engaged in three or more hours of Metabolic Equivalent Tasks (MET) a week — equivalent to jogging, biking, swimming or playing tennis for about a half-hour per week — had a 35 percent lower risk of overall mortality.
Specific to walking, the researchers found that men who walked four or more hours a week had a 23 percent lower risk of all-cause mortality compared to men who walked less than 20 minutes per week. Men who walked 90 or more minutes at a normal to brisk pace had a 51 percent lower risk of death from any cause than men who walked less than 90 minutes at an easy walking pace.
Walking didn't show any effect on prostate cancer specific mortality, but more strenuous exercising did. Men who engaged in five or more hours of vigorous physical activity a week were at a decreased risk of dying from their prostate cancer.
"This is the first large population study to examine exercise in relation to mortality in prostate cancer survivors," said Kenfield. Previous studies focused on how exercise affects risk of developing prostate cancer. Kenfield said that researchers aren't sure of the exact molecular effects exercise has on prostate cancer, but exercise is known to influence a number of hormones hypothesized to stimulate prostate cancer, boost immune function and reduce inflammation.
"How these factors may work together to affect prostate cancer biologically is still being studied," she said. "For now, our data indicate that for prostate cancer survivors, a moderate amount of regular exercise may improve overall survival, while five or more hours per week of vigorous exercise may decrease the death rate due to prostate cancer specifically."
ScienceDaily (Dec. 8, 2009)
While it is too early for physicians to start advising their male patients to take up the habit of regular coffee drinking, data presented at the American Association for Cancer Research Frontiers in Cancer Prevention Research Conference revealed a strong inverse association between coffee consumption and the risk of lethal and advanced prostate cancers.
"Coffee has effects on insulin and glucose metabolism as well as sex hormone levels, all of which play a role in prostate cancer. It was plausible that there may be an association between coffee and prostate cancer," said Kathryn M. Wilson, Ph.D., a postdoctoral fellow at the Channing Laboratory, Harvard Medical School and the Harvard School of Public Health.
In a prospective investigation, Wilson and colleagues found that men who drank the most coffee had a 60 percent lower risk of aggressive prostate cancer than men who did not drink any coffee. This is the first study of its kind to look at both overall risk of prostate cancer and risk of localized, advanced and lethal disease.
"Few studies have looked prospectively at this association, and none have looked at coffee and specific prostate cancer outcomes," said Wilson. "We specifically looked at different types of prostate cancer, such as advanced vs. localized cancers or high-grade vs. low-grade cancers."
Caffeine is actually not the key factor in this association, according to Wilson. The researchers are unsure which components of the beverage are most important, as coffee contains many biologically active compounds like antioxidants and minerals.
Using the Health Professionals' Follow-Up Study, the researchers documented the regular and decaffeinated coffee intake of nearly 50,000 men every four years from 1986 to 2006; 4,975 of these men developed prostate cancer over that time. They also examined the cross-sectional association between coffee consumption and levels of circulating hormones in blood samples collected from a subset of men in the cohort.
"Very few lifestyle factors have been consistently associated with prostate cancer risk, especially with risk of aggressive disease, so it would be very exciting if this association is confirmed in other studies," said Wilson. "Our results do suggest there is no reason to stop drinking coffee out of any concern about prostate cancer."
This association might also help understand the biology of prostate cancer and possible chemoprevention measures.
by Ford Vox
December 04, 2009 - Women were the beneficiaries of the first cancer vaccine―Gardasil, approved in 2006 to prevent cervical cancer. Several weeks ago, the same drug was made available to young males to prevent genital warts. And now it looks as if the first vaccine approved to fight cancer, by enhancing the body's immune response to cancer cells, will benefit males. Last month the Food and Drug Administration committed to deciding the fate of the prostate cancer vaccine Provenge by May 1, 2010. Prostate cancer is an appealing target because it moves slowly (even men whose cancer comes back after prostate surgery often live for well over a decade). That wide window of opportunity gives a vaccine time to prompt the immune system into fighting the body's own cells when they've become cancerous. (The immune system routinely fends off some tumors on its own, generally tiny cancers that are never detected, much less diagnosed.)
But while Provenge is on track to enter the market first, a less-sexy vaccine that hasn't caught the eye of biotech investors could work just as well at a much lower cost. To the chagrin of patient advocates (and investors), the FDA ruled against allowing Provenge into doctor's hands back in 2007 when the results of its large Phase III trial came in. The trial supported the vaccine's effectiveness---men with advanced prostate cancer lived several months longer after getting the vaccine. But Dendreon, the company that owns the technology, hadn't set out to judge the vaccine's value for extending life. The company had designed the trial, and had so informed the FDA, to assess disease progression---how fast the cancer grew and spread. Those results didn't show that the drug offered a statistically significant improvement. New goal, new game, dictated the FDA. The company had to fund a second large trial, this time designed explicitly to test for survival benefit, if it was ever to see its product enter the U.S. market. The results, announced in April, showed that patients with advanced metastatic prostate cancer who had failed other treatments lived four months longer, on average, if they got the Provenge vaccine. That's statistically significant, but is it clinically significant? Dendreon wants patients and doctors, not the FDA, to decide.
Provenge isn't your typical vaccine. It's custom-made from each patient's dendritic cells. These specialized cells mop up foreign molecules (antigens) and then show them off to the immune system's T-cells. If the T-cells don't like what they see, they seek and destroy any cells that carry the antigen, even the body's own cells. To make the Provenge vaccine, technicians must culture a patient's dendritic cells and expose them to an antigen called PAP, found in cancerous prostate tissue. After the cells take up the antigen, they are reintroduced into the patient's bloodstream in a series of three injections to begin schooling the immune system. Because of all this high-tech labor, Provenge will be very expensive, which has attracted the interest of a lot of investors. A few months more of life for a hefty price is all that most cancer therapies offer, and that won't change with this vaccine.
Now for the cheaper way—David Lubaroff's old-school approach. Lubaroff, director of urology research at the University of Iowa, has fashioned a vaccine from a common cold virus. It can be produced inexpensively in mass quantities like the influenza vaccine. Lubaroff and his team inserted the genetic code for prostate-specific antigen, which is generated by prostate cancer cells, into a weakened virus. When a prostate cancer patient gets Lubaroff's PSA vaccine, the weakened virus causes the body's immune system to think that PSA is a foreign intruder like rest of the virus's proteins, and the T-cells go on a search-and-destroy mission against the invading cancer cells. Lubaroff has already demonstrated this fact in animal models, and this month in the journal Clinical Cancer Research, he reports on the vaccine's first human trial. Only 32 men with advanced prostate cancer got the vaccine. The group was so small because the goal of such a Phase I trial is only to determine whether a drug is safe. That's also why investigators only enrolled men with severe disease who were out of other options. There were no serious side effects. As for cancer fighting, over half of the patients lived longer than would be expected—three patients lived close to four years longer. But the study was too small to say much more.
Men with localized prostate cancer could end up benefiting from a vaccine, but they'd have to get the vaccine only after a prostatectomy to remove the prostate gland. Cancer-fighting vaccines are designed to target your own tissues, and even healthy prostates put out PSA. If you got Lubaroff's vaccine prior to prostatectomy, you'd have a painful inflammation of the prostate gland (prostatitis) as your immune system attacked PSA-producing cells. But while Lubaroff's vaccine and Provenge are being tested in men who have cancer that's spread elsewhere in the body, both vaccines may be more effective if given before that happens. For one thing, men who've received chemotherapy, like some of those in the vaccine trials, may have worn-out immune systems that can't take full advantage of the vaccine's stimulation. For another, it makes sense to nip a cancer in the bud.
If the FDA approves Provenge without specific and strong restrictions, some doctors are sure to use it on patients with localized prostate cancer, and they'll be theoretically correct in doing that. "We thought it would be a harder sell" to do a trial in men with less-advanced disease, says Lubaroff. He thinks cancer vaccines like his would work as effectively, perhaps even more so, in men with cancer that hasn't spread. He has a larger Phase II trial underway, funded by the Department of Defense. For a big Phase III trial like those backing up Provenge, Lubaroff knows he'll need pharmaceutical sponsorship. Will he get such backing? Lubaroff's vaccine is a one-shot, one-size-fits-all deal; there's little opportunity for big money to be made from its manufacture or on the healthcare provider's end. Even the seasonal flu vaccine, which goes out to a far larger "customer base," wouldn't be feasible without special government concessions and sponsorship. But if Provenge goes on the market and doctors offer it to men without advanced disease, the expense will put a huge strain on the healthcare system. If the government truly wants healthcare that is more efficient and affordable, wouldn't it make sense to should seek out and accelerate the development and approval of simple, cheap drugs—like Lubaroff's vaccine?
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The Santa Cruz County Prostate Cancer Support Group does not endorse any provider, organization, product or individual. All medical decisions should be made with the advice and consultation of medical professionals.
Many THANKS to the American Cancer Society for assisting with the printing and mailing of this newsletter and the Katz Cancer Resource Center for allowing us to use their facility.