Prostate Cancer Detection

“The article below was found on the medical x press blog online.  It highlights research related to DNA methylation which may play a vital role in the development of more specific biomarkers used for earlier prostate cancer detection.  In the era when the utility of the PSA test is continuously being questioned, the need for more sensitive and specific biomarkers is of paramount importance.  Miami urologists David Robbins, MD and Amery Wirtshafter, MD are experts in the field of prostate cancer detection and treatment and employ the most up to date modalities in the fight against prostate cancer.”  David Robbins , MD. 

 

Researchers discover biomarkers for prostate cancer detection, recurrence May 14, 2012 in Cancer Alterations to the “on-off” switches of genes occur early in the development of prostate cancer and could be used as biomarkers to detect the disease months or even years earlier than current approaches, a Mayo Clinic study has found. These biomarkers — known as DNA methylation profiles — also can predict if the cancer is going to recur and if that recurrence will remain localized to the prostate or, instead, spread to other organs. The study, published in the journal Clinical Cancer Research, is the first to capture the methylation changes that occur across the entire human genome in prostate cancer. Ads by Google Prostate Cancer Failures – Hope for treatment failures/ Rising PSA after treatment – http://www.panamhifu.com Cancer Treatment Options – Diagnosed w/Adenocarcinoma? Learn About New Treatment Options at CTCA – http://www.CancerCenter.com The discovery could someday help physicians diagnose prostate cancer earlier and make more effective treatment decisions to improve cure rates and reduce deaths. It also points to the development of new drugs that reverse the DNA methylation changes, turning the “off” switch back “on” and returning the genetic code to its normal, noncancerous state. “Our approach is more accurate and reliable than the widely used PSA (prostate-specific antigen) test,” says senior author Krishna Donkena, Ph.D., a Mayo Clinic molecular biologist. The PSA test detects any prostate abnormality, whether inflammation, cancer, infection or enlargement, while the DNA methylation changes are specific to prostate cancer, she says. Though the instructions for all the cell’s activities lie within the genes, whether a particular gene is turned “off” or “on” is determined by the presence or absence of specific chemical tags or methyl groups — methylation — along the underlying DNA of cells. When this process of DNA methylation turns off the activity of tumor suppressor genes, cancer develops. Dr. Donkena and her colleagues analyzed the methylation status of 14,495 genes from 238 prostate cancer patients. The patients included people who remained cancer-free after treatment, those who had a localized tumor recurrence and those whose cancer spread. The researchers found that the DNA methylation changes that occurred during the earliest stages of prostate cancer development were nearly identical in all patients. Having discovered DNA methylation patterns that could distinguish between healthy and cancerous tissue, the researchers then searched for similar biomarkers that could distinguish between patients with varying levels of recurrence risk. They found distinct methylation alterations that corresponded to whether a patient had a slow-growing tumor known as an indolent tumor, or had a more aggressive one. If physicians can determine what type of tumor patients have, they can avoid exposing patients with indolent tumors to unnecessary treatment, and can treat those with aggressive tumors earlier and more effectively, Dr. Donkena says. Dr. Donkena and her colleagues are working to develop a DNA methylation test that is more cost-effective and practical for use in clinical settings. Currently, the test relies on microarray or gene “chip” technology that assesses methylation status of genes across an entire genome. The researchers are trying to generate more economical custom microarray to specifically look at only the genes that predict the development of prostate cancer or recurrence. They also hope to develop drugs that can reverse DNA methylation in prostate cancer cells. Similar drugs are already being used to treat certain forms of leukemia. Journal reference: Clinical Cancer Research Provided by Mayo Clinic

Read more at: http://medicalxpress.com/news/2012-05-biomarkers-prostate-cancer-recurrence.html#jCp

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Survey of Top Doctors Finds Widespread Support for PSA Screening

 

 

Survey of Top Doctors Finds Widespread Support for PSA Screening

Top Doctors strongly disagree with government task force proposal to drop use of prostate cancer test

October 28, 2011 RSS Feed Print

 

PSA screening for prostate cancer has been a hot topic in the urology news not only for patients in Miami, but throughout the country.  The U.S. Preventive Services Task Force’s decision to downgrade the recommendation for PSA screening for prostate cancer has not been supported by the either polled urologists or primary care physicians.  This article highlights topics and opinions in the current debate over PSA screening for prostate cancer.”

In an exclusive new survey of Top Doctors conducted by U.S. News & World Report, virtually all responding urologists and more than 60 percent of internal-medicine specialists rejected the recent proposal by a high-level government advisory committee to end routine PSA testing, which is meant to catch prostate cancer early.

An estimated 20 million men a year undergo PSA screening, which determines the blood level of a protein called prostate-specific antigen; nearly 250,000 of them are diagnosed with prostate cancer. The proposal, issued by the U.S. Preventive Services Task Force, advises doctors not to screen patients with the PSA test unless they have symptoms that are “highly suspicious” for prostate cancer.

“If you argue that you should not use PSA testing at all in [men without symptoms], you’re essentially saying you don’t want to find prostate cancer at a curable stage,” says Dr. Samir S. Taneja, director of urologic cancer at NYU Langone Medical Center and a responder to last week’s U.S. News survey.

The government task force found little evidence that screening men with the PSA test significantly reduces deaths from prostate cancer. Whatever small benefit there might be, the task force concluded, is outweighed by the risk of an incorrect diagnosis or unnecessary procedure leading to death or complications. About a third of men treated for prostate cancer suffer urinary incontinence, impotence, or both, and about 1 in every 200 dies within 30 days from complications of surgery.

Doctors have debated the risks and benefits of the PSA test since 1994, when the Food and Drug Administration approved it for cancer screening. Even the test’s supporters acknowledge that it is inherently imprecise. A high PSA level may indicate the presence of a tumor—or it may not. Nor is a low PSA level necessarily an all-clear. Moreover, the test cannot distinguish between a typical tumor, which grows so slowly that the threat is minimal, and one that is aggressive and potentially lethal.

To determine whether some of the nation’s best doctors agree with the task force’s proposed recommendation, U.S. News surveyed more than 600 urologists and internists who are recognized as Top Doctors by U.S. News and Castle Connolly Medical Ltd. More than a third of the physicians responded. (For a breakdown of the questions and responses, see Behind the U.S. News Top Doctors Survey on PSA Screening.)

About 95 percent of the responding urologists felt that doctors should continue to advise men starting at age 50, when testing typically begins, to have PSA screenings as part of a routine physical exam, contrary to the task force’s recommendation. They included themselves in that group; 97 percent indicated they would be tested starting at 50. The internists were less unanimous—about 40 percent agreed with the proposed recommendation to end routine testing. But 72 percent of the responding male internists indicated that they themselves would have the test starting at age 50.

The vast majority of the survey respondents sent U.S. News comments as well. “Can you put a price on being saved from dying of cancer?” wrote Dr. Ernest H. Agatstein, a urologist with Paletz Agatstein Urology Medical Group in Downey, Calif.

PSA screening is “an awesome test,” wrote Dr. Richard J. Macchia, a urologist at Cleveland Clinic Florida in Weston. “When I was young,” he went on, “almost all the prostate cancer patients I saw had metastatic disease at diagnosis. Now, in patients who have their PSAs checked, I almost never see metastatic disease at the time of diagnosis. We can cure metastatic diseases only rarely.”

Task force member Dr. Michael LeFevre, professor of family medicine at the University of Missouri School of Medicine in Columbia, says the impassioned backlash against the draft task force recommendation is unsurprising. “When science doesn’t give us the result we want, it’s pretty unusual for the medical and patient communities to turn on a dime and say, ‘We were wrong,’ ” he told U.S. News.

The task force reviewed over 8,000 summaries of research studies related to prostate cancer screening and treatment. Many were eliminated because of major flaws. The strongest evidence came from two large trials that examined the impact of prostate cancer screening on death rates.

The first was a U.S. trial of nearly 80,000 men between the ages of 55 and 74. The men were divided into two groups: One had PSA testing and a digital rectal exam and the other had only a rectal exam. The study found that screening boosted the number of diagnosed cancers by 20 percent, but also that diagnosing the additional cancers did not reduce overall death rates over 10 years of follow-up.

The second study, involving 182,000 men and carried out in Europe, found that PSA screening reduced the number of cancer deaths by about 6 or 7 for every 10,000 men tested. Based on these results, the task force concluded, 48 men would have to be treated to prevent one prostate cancer death, exposing 47 men to the dangers of treatment.

Dr. Patrick Walsh of Johns Hopkins Hospital, a pioneer of radical prostatectomy—surgical removal of the entire prostate gland—takes issue with the task force assessment. He points to American Cancer Society statistics that show a 40 percent decrease in prostate cancer deaths since 1994, a decline that he attributes to the introduction of PSA screening.

Dr. LeFevre counters that the downward trend in prostate cancer deaths began before the PSA test was widely adopted, which suggests that the test wasn’t the driving force.

Dr. Alan Wein, chief of urology at the Hospital of the University of Pennsylvania, told U.S. News in an interview that the two sides may not be as far apart as they seem. On the one hand, he says, “mortality from prostate cancer has decreased, and it happens to coincide with PSA screening. And there’s no question that, before PSA screening, it was common to see people come in with metastatic or very advanced local disease. You rarely see that now. It may not be cause and effect, but those are the facts.”

On the other hand, says Wein, there’s also no question that too many patients are encouraged to seek radical prostatectomy or radiation and too few are informed about a third option known as watchful waiting, in which doctor and patient use periodic PSA tests, frequent physical exams, and biopsies to track a tumor’s growth and decide when, if ever, to pursue aggressive treatment.

“I would hope that the whole issue helps urologists understand that we have to be forthright with patients about our expectations for treatment and those circumstances when it’s most reasonable to watch and wait,” Wein says.

The U.S. Preventive Services Task Force recommendation, which was made public October 11, is not final. It could change after the medical community and the public submit formal comments.