Featured Research

from universities, journals, and other organizations

Leading experts disagree on evidence behind prostate cancer screening recommendations

Date:
March 25, 2013
Source:
Wolters Kluwer Health: Lippincott Williams & Wilkins
Summary:
Do the results of recent randomized trials justify the recent U.S. recommendation against yearly measurement of prostate-specific antigen (PSA) as a screening test for prostate cancer?

Do the results of recent randomized trials justify the recent U.S. recommendation against yearly measurement of prostate-specific antigen (PSA) as a screening test for prostate cancer? That's the topic of debate in a special "point/counterpoint" section in the April issue of Medical Care.

The recommendation against routine PSA measurement relies too heavily on randomized trial data, according to an article by Ruth Etzioni, PhD, of Fred Hutchinson Cancer Research Center, Seattle, and colleagues. They argue that modeling studies provide a truer picture of the long-term benefits of PSA screening. But Dr Joy Melnikow of University of California, Davis, and colleagues disagree, asserting that randomized trials provide a sufficient level of certainty to recommend against PSA screening.

Point: Short-Term Trials Don't Reflect Long-Term Risk Last year, the U.S. Preventive Services Task Force recommended against routine PSA measurement to screen for prostate cancer. The recommendation was mainly based on two recent studies -- one conducted in Europe and one in the United States -- in which men were randomly assigned to annual PSA screening or no screening. Both studies concluded that annual screening did not reduce the risk of death from prostate cancer.

But randomized trials have important limitations as a basis for screening policies, according to Dr Etzioni and colleagues. They note that screening trials generally provide short-term results, in contrast to the long-term results generated by population-wide screening programs. They argue that taking the randomized trial data at face value "misrepresents the likely long-term population impact of PSA screening (relative to no screening) in the United States."

Dr Etzioni and coauthors discuss the results of modeling studies that give a different picture of the benefits of PSA screening. Based on those models, screening may explain 45 percent of recent declines in U.S. deaths from prostate cancer, while changes in treatment account for 33 percent. When the randomized trial data are extrapolated to the U.S. population over the long term, the absolute reduction in deaths attributed to screening appears at least five times greater than in the original trial reports.

Modeling studies also suggest a lower rate of overdiagnosis -- screening detection of slow-growing prostate cancers that otherwise would have caused no harm -- than reported in the trials. Dr Etzioni and colleagues conclude, "With a disease whose hallmark is a lengthy natural history, the harms of developing cancer screening policies based primarily on limited-duration screening trials may well outweigh the benefits."

Counterpoint: Trials Are Best Evidence on Screening Effects But in their "Counterpoint" essay, by Dr Melnikow and colleagues notes that the U.S. and European trials provided 11 to 13 years' follow-up in more than 250,000 individuals. They also point out that the U.S. trial was highly representative of the population and showed no reduction in death resulting from annual PSA testing. (Dr Melnikow and colleagues were members of the U.S. Preventive Services Task Force when the recommendation was made.)

They add that, because of "competing causes of death," it becomes even less likely that a large reduction in deaths from prostate cancer will appear over long-term follow-up. The chances of overdiagnosis and potential harms from screening are also likely to increase with continued aging. Dr Melnikow and coauthors conclude, "Projections from models are subject to mistaken assumptions and investigator biases, and should not be accorded the same weight as evidence from randomized controlled trials."

In an editorial response, Dr Etzioni's group points out that modeling plays an essential role in addressing questions about the harms and benefits of screening. "While we acknowledge the centrality of screening trials in the policy process," they write, "we maintain that modeling constitutes a powerful tool for screening trial interpretation and screening policy development."

The debate is "no mere academic exercise," according to an editorial by Ronnie D. Horner, PhD, of University of Cincinnati Medical Center. With the increased emphasis on disease prevention under health care reform, it is essential to offer those services most likely to represent value -- including cancer screenings. While there's no easy answer, Dr Horner writes, "I am hopeful that this Point-Counterpoint exchange will initiate a discussion among healthcare scientists that will yield greater guidance for determining whether a health care service is, indeed, value health care."


Story Source:

The above story is based on materials provided by Wolters Kluwer Health: Lippincott Williams & Wilkins. Note: Materials may be edited for content and length.


Journal References:

  1. Joy Melnikow, Michael LeFevre, Timothy J. Wilt, Virginia A. Moyer. Counterpoint. Medical Care, 2013; 1 DOI: 10.1097/MLR.0b013e31828a67d3
  2. Ruth Etzioni, Roman Gulati. Response. Medical Care, 2013; 51 (4): 304 DOI: 10.1097/MLR.0b013e31828a7e1a

Cite This Page:

Wolters Kluwer Health: Lippincott Williams & Wilkins. "Leading experts disagree on evidence behind prostate cancer screening recommendations." ScienceDaily. ScienceDaily, 25 March 2013. <www.sciencedaily.com/releases/2013/03/130325111004.htm>.
Wolters Kluwer Health: Lippincott Williams & Wilkins. (2013, March 25). Leading experts disagree on evidence behind prostate cancer screening recommendations. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2013/03/130325111004.htm
Wolters Kluwer Health: Lippincott Williams & Wilkins. "Leading experts disagree on evidence behind prostate cancer screening recommendations." ScienceDaily. www.sciencedaily.com/releases/2013/03/130325111004.htm (accessed October 20, 2014).

Share This



More Health & Medicine News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Microneedle Patch Promises Painless Pricks

Microneedle Patch Promises Painless Pricks

Reuters - Innovations Video Online (Oct. 18, 2014) Researchers at The National University of Singapore have invented a new microneedle patch that could offer a faster and less painful delivery of drugs such as insulin and painkillers. Video provided by Reuters
Powered by NewsLook.com
Raw: Nurse Nina Pham Arrives in Maryland

Raw: Nurse Nina Pham Arrives in Maryland

AP (Oct. 17, 2014) The first nurse to be diagnosed with Ebola at a Dallas hospital walked down the stairs of an executive jet into an ambulance at an airport in Frederick, Maryland, on Thursday. Pham will be treated at the National Institutes of Health. (Oct. 16) Video provided by AP
Powered by NewsLook.com
Raw: Cruise Ship Returns to US Over Ebola Fears

Raw: Cruise Ship Returns to US Over Ebola Fears

AP (Oct. 17, 2014) A Caribbean cruise ship carrying a Dallas health care worker who is being monitored for signs of the Ebola virus is heading back to Texas, US, after being refused permission to dock in Cozumel, Mexico. (Oct. 17) Video provided by AP
Powered by NewsLook.com
Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

AFP (Oct. 17, 2014) All four suspected Ebola cases admitted to hospitals in Spain on Thursday have tested negative for the deadly virus in a first round of tests, the government said Friday. Duration: 00:55 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins