Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fewer false alarms when mammographers have greater experience screening healthy breasts

02.03.2005


Physicians who specialize in screening mammography and who have at least 25 years of experience are more accurate at interpreting the images and subject fewer women to the anxiety of false positives for cancer, when compared to physicians with less experience or those who don’t have the same focus, according to a new study. The research was led by a UCSF team and is published in the March 2 issue of the Journal of the National Cancer Institute.

Screening mammograms are the type most women get. These images are designed to discover any cancer that might be hidden in women with no breast symptoms. Women who have a history of breast cancer or other symptoms -- or who experience symptoms at the time of their exam -- receive diagnostic mammograms. After two to five asymptomic years, their physicians will usually revert to screening mammography.

Study findings showed that the more experienced physicians not only properly identified cancer, they also were 50 percent less likely to falsely characterize a mammogram as abnormal. In addition, the study found dramatic variability in physician accuracy. For example, physicians on average detected 77 percent of cancers, but for individual physicians the detection rate ranged from 29-97 percent. The average false positive rate was 10 percent, while the rate for individual physicians ranged from 1-29 percent.



According to the UCSF researchers, it has already been well documented in scientific literature that patient characteristics -- such as breast tissue density -- can be negatively associated with mammogram accuracy and those characteristics largely cannot be changed. They chose, therefore, to focus their study on what physician characteristics could be associated with accuracy. They studied more than 1.2 million mammograms paired with data from statewide cancer registries in four states.

The study found that physicians who read a greater number of mammograms identified cancers without mistaking normal tissue for a malignancy with greater accuracy than physicians whose volume was not as high. In general, the false-positive rate declined with increasing physician age, with increasing time since receipt of medical degree, and with increasing annual volume. Additionally, those physicians who focused their practice on screening, as opposed to diagnostic mammography, had a lower false-positive rate.

Study data came from four sites that participate in the National Cancer Institute- funded Breast Cancer Surveillance Consortium. Those sites -- San Francisco, New Mexico, Vermont and Colorado -- prospectively collect mammographic interpretations. Researchers linked the interpretation data to cancer registries and then to physician information from the American Medical Association. They studied 209 physicians who interpreted 1.2 million mammograms from January 1, 1995 through December 31, 2000 including 7143 that were associated with breast cancer.

The minimum number of mammograms a US physician can read and still be considered qualified under FDA regulations is 960 within a two-year period, or approximately 10 mammograms per week, according to the Mammography Quality Standards Act of 1992.

"Raising the annual volume requirements in the Act might improve the overall quality of screening mammography in the US," said principal investigator Rebecca Smith Bindman, MD, UCSF associate professor of radiology, epidemiology/biostatistics, and obstetrics, gynecology and reproductive sciences. She also is director of the UCSF Radiology Outcomes Research Lab and part of the breast oncology program of the UCSF Comprehensive Cancer Center.

The authors hypothesize that physicians who read more mammograms overall and who have been reading them longer develop a higher threshold for identifying cancer and overall do better. Those who read a higher proportion of diagnostic mammograms, they say, may tend to develop a lower threshold, expecting a higher rate of cancer.

"Compared with those who read the minimum number allowed by the Act and who have less focus on screening, physicians who focus on screening and who interpret 2,500-4,000 mammograms annually have 50 percent fewer false-positive diagnoses while detecting approximately one less cancer per 2,500 mammograms," the authors wrote.

Smith Bindman added, "The variation we found was dramatic. We recommend explicit discussion of what the goals of mammography should be, and sooner rather than later."

If the goal is to maximize the identification of cancer while achieving a reasonable false-positive rate, raising the minimum required under the Act would make sense, according to Smith-Bindman. Although fewer doctors would subsequently be available for reading mammograms, any resulting increased barriers to healthcare delivery could be managed, she said. "Change would need to occur slowly to prevent a shortage of physicians. But the payoff would be fewer false alarms for women."

Eve Harris | EurekAlert!
Further information:
http://www.ucsf.edu

More articles from Health and Medicine:

nachricht 3D images of cancer cells in the body: Medical physicists from Halle present new method
16.05.2018 | Martin-Luther-Universität Halle-Wittenberg

nachricht Better equipped in the fight against lung cancer
16.05.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Designer cells: artificial enzyme can activate a gene switch

22.05.2018 | Life Sciences

PR of MCC: Carbon removal from atmosphere unavoidable for 1.5 degree target

22.05.2018 | Earth Sciences

Achema 2018: New camera system monitors distillation and helps save energy

22.05.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>