Featured Research

from universities, journals, and other organizations

Breast Cancer Screening Exams Produce High Level Of False-Positive Results

Date:
April 17, 1998
Source:
University Of Washington
Summary:
Researchers at the University of Washington and Harvard University have determined that at least one woman in two will receive a false-positive result after having annual screening mammograms for a decade, and almost 20 percent of women will undergo a biopsy.

Researchers at the University of Washington and Harvard University have determined that at least one woman in two will receive a false-positive result after having annual screening mammograms for a decade, and almost 20 percent of women will undergo a biopsy.

Their study also indicates that almost 25 percent of women will have a false-positive result at some point in 10 years of clinical (physical) breast examinations.

Results of the study, led by Dr. Joann G. Elmore of the University of Washington School of Medicine, are published in the April 16 issue of the New England Journal of Medicine. The study was conducted at Harvard Pilgrim Health Care, a large health maintenance organization affiliated with Harvard Medical School.

A woman with a positive result must go through additional workup before she can be sure that the breast abnormality is not cancer. Such workups can include mammograms, ultrasounds, outpatient visits and biopsies. When she does not have cancer, it is called a false-positive.

Elmore's interest in performing the study stemmed from the concerns and anxiety expressed by her patients over abnormal screening results. Earlier research has shown that, nationally, about one mammogram in 10 produces a false-positive.

"If a woman is screened for breast cancer every year between age 40 and age 70, she could have a total of 30 screening mammograms and 30 clinical breast exams," she said. "There's a high chance of a woman having an alarming false-positive episode."

Elmore and her team looked at computerized records for 10 years of breast-cancer screening and diagnostic evaluations performed on 2,400 women aged 40 to 69 at entry into the study. A total of 9,762 screening mammograms were read by 93 radiologists, and 10,905 screening clinical breast exams were performed by 381 health care providers.

With a median of four mammograms per woman, 23.8 percent had at least one false-positive mammogram over the 10-year period. With a median of five clinical breast examinations per woman, 13.4 percent had at least one false-positive. A total of 31.7 percent had at least one false-positive result for either test.

The false positives led to 870 outpatient appointments, 539 diagnostic mammograms, 186 ultrasound examinations, 188 biopsies, and one hospitalization.

"For every $100 spent for screening, an additional $33 was spent to evaluate the false-positive results," said Elmore.

The investigators believe the study may, in fact, underestimate the false-positive rate for mammography in the United States: the overall rate of abnormal screening mammograms at Harvard Pilgrim Health Care was only 6.5 percent, whereas the national rate is nearly twice as high. In comparison, only 2 percent to 5 percent of screening mammograms are read as abnormal in Sweden.

"The possibility that radiologists in the United States are interpreting too many mammograms as abnormal should be investigated," they state.

If their findings are representative, the investigators estimate that up to 16 million women in the U.S. would have at least one false-positive mammogram and seven million would have at least one false-positive clinical breast examination after 10 years of annual screening.

"This study indicates that we need to develop ways to reduce the false-positive results of breast-cancer screening and their associated psychologic and economic costs," said Elmore. "We hope this study will allow women to better understand their risk of a false-positive screening test, helping to reduce their anxiety when an abnormality is noted."

The researchers recommend that women be informed about the chances of a false-positive test result, and that healthcare providers be trained to deal with such results.

Elmore is an assistant professor of medicine and epidemiology at the University of Washington's School of Medicine and School of Public Health and Community Medicine. Co-investigators are Dr. Mary Barton and Dr. Suzanne Fletcher of the Department of Ambulatory Care and Prevention, a jointly-run department of Harvard Medical School and Harvard Pilgrim Health Care; Dr. Philip Arena, director of medical imaging at Harvard Vanguard Medical Associates and clinical professor of radiology at Boston University School of Medicine; Victoria Moceri, a Ph.D. candidate in epidemiology at the UW; and Sarah Polk, a premedical student.

The research was supported by Yale University's Claude Pepper Aging Center, the American Cancer Society, the Robert Wood Johnson Foundation and the Harvard Pilgrim Health Care Foundation. Harvard Pilgrim Health Care, a not-for-profit health plan, has 1.3 million members in Massachusetts, Rhode Island, New Hampshire and Maine.


Story Source:

The above story is based on materials provided by University Of Washington. Note: Materials may be edited for content and length.


Cite This Page:

University Of Washington. "Breast Cancer Screening Exams Produce High Level Of False-Positive Results." ScienceDaily. ScienceDaily, 17 April 1998. <www.sciencedaily.com/releases/1998/04/980417082059.htm>.
University Of Washington. (1998, April 17). Breast Cancer Screening Exams Produce High Level Of False-Positive Results. ScienceDaily. Retrieved September 19, 2014 from www.sciencedaily.com/releases/1998/04/980417082059.htm
University Of Washington. "Breast Cancer Screening Exams Produce High Level Of False-Positive Results." ScienceDaily. www.sciencedaily.com/releases/1998/04/980417082059.htm (accessed September 19, 2014).

Share This



More Health & Medicine News

Friday, September 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
Powered by NewsLook.com
How The 'Angelina Jolie Effect' Increased Cancer Screenings

How The 'Angelina Jolie Effect' Increased Cancer Screenings

Newsy (Sep. 19, 2014) Angelina's Jolie's decision to undergo a preventative mastectomy in 2013 inspired many women to seek early screenings for the disease. Video provided by Newsy
Powered by NewsLook.com
The Cost of Ebola

The Cost of Ebola

Reuters - Business Video Online (Sep. 18, 2014) As Sierra Leone prepares for a three-day "lockdown" in its latest bid to stem the spread of Ebola, Ciara Lee looks at the financial implications of fighting the largest ever outbreak of the disease. Video provided by Reuters
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:
from the past week

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