Panels recommend gearing back on prostate-cancer screenings, cancer

December 28, 2011 By Fred Tasker

A blood screening result that suggests prostate cancer is bound to provoke high anxiety - even though up to 80 percent of those findings turn out to be false positives.

Anxiety deepens, of course, if a biopsy confirms a , to the extent that many demand surgery or radiation even when they don't need it.

Now, two national health panels have made startling recommendations that call into question the way doctors have been handling prostate cancer testing and treatment. One panel said men should skip standard prostate-specific antigen, or PSA, testing unless they have symptoms such as urinary blockage or pain. A second panel urged many men with low-risk to turn to "active surveillance" rather than immediate surgery or radiation.

The recommendations - the first is part of a draft report by the U.S. Preventive Services task force in October, the second came from a panel convened by the National Institutes of Health this month - have generated controversy, even as researchers work to develop better methods. "Skipping the PSA is the wrong way to approach it. It's an extreme viewpoint that will have terrible ramifications on public health if it goes forward," says Dr. Bruce Kava, interim chair of urology at the University of Miami Miller School of Medicine.

"I've had patients whose cancer was discovered by a PSA test," adds Dr. Rakesh Singal, a urologist and prostate cancer researcher at the University of Miami medical school.

The task force recommendation came after a months-long study of clinical trials around the world. "The common perception that PSA-based early detection of prostate cancer prolongs lives is not supported by the scientific evidence," the draft report said. The task force is a congressionally mandated panel of doctors, nurses and other specialists that develops recommendations for doctors and hospitals.

The second recommendation, from a "consensus panel" of 14 researchers and clinicians convened this month by the National Institutes of Health, tackled the treatment side: "Treatment of low-risk prostate cancer with radical prostatectomy or radiation therapy leads to side effects such as impotence and incontinence. Active surveillance has emerged as a viable option."

Responding to those concerns, researchers in South Florida and around the world are working on better screening tests to replace or at least supplement the PSA test, which has been use since 1986. Such improved tests could make the screening controversy "moot," the U.S. Cancer Foundation says. It says studies also are under way to better guide how aggressive treatment should be when cancer is confirmed.

The prostate, a small-plum-sized gland that sits above the base of the penis and helps produce semen, becomes enlarged in half of all men by age 60, and half of those will have symptoms such as frequent urination, weak stream or inability to completely empty the bladder.

And the symptoms raise the question: Is it benign prostate hyperplasia (enlargement) or prostate cancer? Cancer is not rare. One-third of men ages 40 to 60 and three-quarters of men older than 85 have prostate cancer, federal health officials say - even though most of it is microscopic and clinically insignificant.

Researchers say most of those diagnosed with prostate cancer are likely to grow old and die of something else first. The lifetime risk of death from prostate cancer is only 2.5 percent, and the median age of death from prostate cancer is 80, says the U.S. Centers for Disease Control and Prevention. Still, it's the second greatest cause of male cancer deaths after lung cancer, killing 32,000 men a year.

"We realize it's a dilemma," says Kava, the urologist, calling the number of positive PSA tests that lead to negative biopsies "unacceptably high. ... And biopsies are not innocuous. Some find them painful. Also, false positives can create anxiety, sometimes depression."

Biopsies also cause fever, infection, bleeding and transient urinary difficulty in 68 of every 1,000 procedures, the task force report says. Seeking to balance the benefits of the PSA test against the harms, the task force concluded that men without overt symptoms should skip the PSA tests.

Protest came quickly from the American Urological Association: "We are concerned that the task force's recommendations will ultimately do more harm than good," it said. "It is our feeling that, when interpreted appropriately, (the PSA test) provides important information in diagnosis."

Research at several U.S. universities soon might produce better screening tests to replace or supplement the PSA test, said the California-based Prostate Cancer Foundation, which raises funds for research. Foundation president Jonathan Simons said his group's 2011 annual Scientific Retreat heard presentations of 17 new tests under way that might improve on the PSA.

"The PSA debate can become moot with intensive and accelerated research that delivers a better test," he said.

One new test is being developed by Rakesh, the University of Miami urologist, and a team of researchers who say a DNA blood test may increase the accuracy of diagnosis when added to the PSA test.

"I think it can be very useful in helping decide whether to go on to a biopsy," he says.

The test needs funding for more study, but could be ready in a year or two, he says.

Another promising method, being developed at the University of Michigan Comprehensive Cancer Center by director Arul Chinnaiyan and his team, would use a two-gene DNA test they say is 80 percent accurate to detect prostate cancer. The study was published Aug. 3 in the peer-reviewed journal Science Translational Medicine. The university hopes to offer the test to its patients within a year and to the general public soon after.

But even if new tests improve upon the PSA, it still leaves the issue of treatment for confirmed cases. Anxiety can cause men to demand aggressive treatment even when they don't need it, the task force said.

"Over three quarters of men with localized prostate cancer undergo prostatectomy or radiation therapy," the task force report says. "Radiotherapy and surgery result in adverse effects, including urinary incontinence and erectile dysfunction, in at least 20 percent to 30 percent of men treated with these therapies."

Men with aggressive prostate cancers clearly need aggressive treatment, the task force says. But many others don't need such drastic measures: "Even when asymptomatic cancer is found by PSA, a majority of the tumors will progress so slowly that the man will die of something else."

The report notes there is "no consensus about the best treatment of localized disease."

Kava, the Sylvester urologist, says he has seen anxiety over PSA tests lead men to demand more aggressive treatment than they need.

"We try to temper their emotional response by giving them data," he says. "But we're a patient-driven practice. If they want therapy, we will go forward with it."

Kava says doctors increasingly are turning to two methods of tracking the progression of the cancers - "active surveillance" and "watchful waiting."

A major new active surveillance program funded in 2010 by $5 million from the Prostate Cancer Foundation is the National Proactive Surveillance Network, designed and run by Johns Hopkins University and Cedars-Sinai Medical Center in New York. 

In the program, open to men across the country, local doctors do the testing and submit results to Johns Hopkins online. Men with PSA scores lower than 15 who have biopsy evidence of small-volume, low-grade cancer are examined and their PSA levels analyzed at six-month intervals, with annual biopsies. In the program's first year, only 32 percent of the men followed have progressed to where they need radiation or surgery.

The University of Miami Medical School and Sylvester have similar surveillance programs, Kava says, following more than 800 men with prostate cancer.

For older men and those in poor health from other causes, with life expectancies under 10 years, Kava says less-rigorous "watchful waiting" programs may be appropriate, with fewer biopsies and other intrusive procedures.

Meanwhile, Simons says his foundation is funding more studies into how doctors can identify which tumors need aggressive treatment and which don't. The University of Michigan search for a DNA test to supplement the PSA test also is designed to give better information about how aggressive the cancer is, based on tumor size and appearance under a microscope.

It comes down to this, Simons says: "Experts believe many prostate cancers will never cause a problem the rest of your life, even if you're diagnosed at 50. But others will kill you. We need to understand what makes one prostate cancer indolent while another is lethal.

"The overtreatment of prostate cancer will go away when we can look at a man and say, 'Mr. Jones, this cancer is a turtle, and this one is a shark.' We're a few years away."



How best to detect and treat it?

The gold-standard test for prostate cancer is the praised and vilified PSA test, a blood test that measures a protein that can signal . Or not. In men who got a routine even though they didn't have serious symptoms of pain or blood in the urine or semen, one study said the test found evidence of cancer in 25 percent. Indication of cancer was defined for purposes of that study as a PSA of 4.0 nanograms per milliliter or higher. But subsequent biopsies determined that 80 percent of those "positives" were false. (Higher PSAs are considered more likely to indicate cancer, although the National Cancer Institute says there is no specific normal or abnormal PSA level.)

Explore further: PSA test valuable in predicting biopsy need, low-risk prostate cancer

Related Stories

PSA test valuable in predicting biopsy need, low-risk prostate cancer

October 21, 2011
The prostate-specific antigen test, commonly known as the PSA test, is valuable in predicting which men should have biopsies and which are likely to be diagnosed with low-risk prostate cancer, a Mayo Clinic study has found. ...

New prostate cancer test gives more accurate diagnosis

April 6, 2011
In a large multi-center clinical trial, a new PSA test to screen for prostate cancer more accurately identified men with prostate cancer -- particularly the aggressive form of the disease -- and substantially reduced false ...

Recommendation against PSA test goes too far: expert

October 12, 2011
(Medical Xpress) -- A draft recommendation by the U.S. Preventive Services Task Force calling for an end to routine PSA testing for healthy men age 50 and older goes too far, says a prostate cancer expert at the Siteman Cancer ...

PSA test for men could get a second life for breast cancer in women

July 13, 2011
The widely known PSA blood test for prostate cancer in men may get a second life as a much-needed new test for breast cancer, the most common form of cancer in women worldwide, scientists are reporting in a new study in the ...

When rising PSA means prostate cancer is in patient's future

May 18, 2011
A man's rising PSA (prostate-specific antigen) level over several years – which had been seen as a possible warning sign of prostate cancer – has recently come under fire as a screening test because it sometimes ...

Recommended for you

No dye: Cancer patients' gray hair darkened on immune drugs

July 21, 2017
Cancer patients' gray hair unexpectedly turned youthfully dark while taking novel drugs, and it has doctors scratching their heads.

Shooting the achilles heel of nervous system cancers

July 20, 2017
Virtually all cancer treatments used today also damage normal cells, causing the toxic side effects associated with cancer treatment. A cooperative research team led by researchers at Dartmouth's Norris Cotton Cancer Center ...

Molecular changes with age in normal breast tissue are linked to cancer-related changes

July 20, 2017
Several known factors are associated with a higher risk of breast cancer including increasing age, being overweight after menopause, alcohol intake, and family history. However, the underlying biologic mechanisms through ...

Immune-cell numbers predict response to combination immunotherapy in melanoma

July 20, 2017
Whether a melanoma patient will better respond to a single immunotherapy drug or two in combination depends on the abundance of certain white blood cells within their tumors, according to a new study conducted by UC San Francisco ...

Discovery could lead to better results for patients undergoing radiation

July 19, 2017
More than half of cancer patients undergo radiotherapy, in which high doses of radiation are aimed at diseased tissue to kill cancer cells. But due to a phenomenon known as radiation-induced bystander effect (RIBE), in which ...

Definitive genomic study reveals alterations driving most medulloblastoma brain tumors

July 19, 2017
The most comprehensive analysis yet of medulloblastoma has identified genomic changes responsible for more than 75 percent of the brain tumors, including two new suspected cancer genes that were found exclusively in the least ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.