Original Research
19 July 2016

Variation in Mammographic Breast Density Assessments Among Radiologists in Clinical Practice: A Multicenter Observational Study

Publication: Annals of Internal Medicine
Volume 165, Number 7

Abstract

Background:

About half of the United States has legislation requiring radiology facilities to disclose mammographic breast density information to women, often with language recommending discussion of supplemental screening options for women with dense breasts.

Objective:

To examine variation in breast density assessment across radiologists in clinical practice.

Design:

Cross-sectional and longitudinal analyses of prospectively collected observational data.

Setting:

30 radiology facilities within the 3 breast cancer screening research centers of the Population-based Research Optimizing Screening through Personalized Regimens (PROSPR) consortium.

Participants:

Radiologists who interpreted at least 500 screening mammograms during 2011 to 2013 (n = 83). Data on 216 783 screening mammograms from 145 123 women aged 40 to 89 years were included.

Measurements:

Mammographic breast density, as clinically recorded using the 4 Breast Imaging Reporting and Data System categories (heterogeneously dense and extremely dense categories were considered “dense” for analyses), and patient age, race, and body mass index (BMI).

Results:

Overall, 36.9% of mammograms were rated as showing dense breasts. Across radiologists, this percentage ranged from 6.3% to 84.5% (median, 38.7% [interquartile range, 28.9% to 50.9%]), with multivariable adjustment for patient characteristics having little effect (interquartile range, 29.9% to 50.8%). Examination of patient subgroups revealed that variation in density assessment across radiologists was pervasive in all but the most extreme patient age and BMI combinations. Among women with consecutive mammograms interpreted by different radiologists, 17.2% (5909 of 34 271) had discordant assessments of dense versus nondense status.

Limitation:

Quantitative measures of mammographic breast density were not available for comparison.

Conclusion:

There is wide variation in density assessment across radiologists that should be carefully considered by providers and policymakers when considering supplemental screening strategies. The likelihood of a woman being told she has dense breasts varies substantially according to which radiologist interprets her mammogram.

Primary Funding Source:

National Institutes of Health.

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Information & Authors

Information

Published In

cover image Annals of Internal Medicine
Annals of Internal Medicine
Volume 165Number 74 October 2016
Pages: 457 - 464

History

Published online: 19 July 2016
Published in issue: 4 October 2016

Keywords

Authors

Affiliations

Brian L. Sprague, PhD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Emily F. Conant, MD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Tracy Onega, PhD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Michael P. Garcia, MS
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Elisabeth F. Beaber, PhD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Sally D. Herschorn, MD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Constance D. Lehman, MD, PhD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Anna N.A. Tosteson, ScD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Ronilda Lacson, MD, PhD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Mitchell D. Schnall, MD, PhD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Despina Kontos, PhD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Jennifer S. Haas, MD, MSc
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Donald L. Weaver, MD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
William E. Barlow, PhD
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
on behalf of the PROSPR Consortium
From University of Vermont, Burlington, Vermont; Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Fred Hutchinson Cancer Research Center and Cancer Research and Biostatistics, Seattle, Washington; and Massachusetts General Hospital and Brigham and Women's Hospital, Boston, Massachusetts.
Acknowledgment: The authors thank the participating PROSPR research centers for the data they provided for this study. A list of the PROSPR investigators and contributing research staff is provided at http://healthcaredelivery.cancer.gov/prospr.
Grant Support: This work was supported by the National Cancer Institute–funded PROSPR consortium (U01 CA163304, U54 CA163303, U54 CA163313, and U54 CA163307).
Disclosures: Dr. Sprague reports grants from the National Institutes of Health during the conduct of the study. Dr. Conant reports grants from the National Cancer Institute during the conduct of the study and personal fees from Siemens Healthcare, Hologic, and the International Center for Postgraduate Medical Education outside the submitted work. Dr. Onega reports grants from the National Institutes of Health during the conduct of the study. Mr. Garcia reports grants from the National Institutes of Health during the conduct of the study. Dr. Beaber reports grants from the National Cancer Institute during the conduct of the study. Dr. Herschorn reports grants from the National Cancer Institute during the conduct of the study and stock holdings in Hologic. Dr. Tosteson reports grants from the National Institutes of Health during the conduct of the study. Dr. Lacson reports grants from the National Institutes of Health during the conduct of the study and grants from the Agency for Healthcare Research and Quality outside the submitted work. Dr. Haas reports grants from the National Cancer Institute during the conduct of the study. Dr. Barlow reports grants from the National Cancer Institute during the conduct of the study. Authors not named here have disclosed no conflicts of interest. Disclosures can also be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=M15-2934.
Editors' Disclosures: Christine Laine, MD, MPH, Editor in Chief, reports that she has no financial relationships or interests to disclose. Darren B. Taichman, MD, PhD, Executive Deputy Editor, reports that he has no financial relationships or interests to disclose. Cynthia D. Mulrow, MD, MSc, Senior Deputy Editor, reports that she has no relationships or interests to disclose. Deborah Cotton, MD, MPH, Deputy Editor, reports that she has no financial relationships or interest to disclose. Jaya K. Rao, MD, MHS, Deputy Editor, reports that she has stock holdings/options in Eli Lilly and Pfizer. Sankey V. Williams, MD, Deputy Editor, reports that he has no financial relationships or interests to disclose. Catharine B. Stack, PhD, MS, Deputy Editor for Statistics, reports that she has stock holdings in Pfizer and Johnson & Johnson.
Reproducible Research Statement: Study protocol: Not available. Statistical code: Available from Dr. Barlow (e-mail, [email protected]). Data set: Individual data are not available, but research collaboration on this topic may be possible by contacting Dr. Barlow (e-mail, [email protected]).
Corresponding Author: Brian L. Sprague, PhD, Office of Health Promotion Research, University of Vermont, 1 South Prospect Street, UHC Room 4425, Burlington, VT 05401; e-mail, [email protected].
Current Author Addresses: Dr. Sprague: Office of Health Promotion Research, University of Vermont, 1 South Prospect Street, UHC Room 4425, Burlington, VT 05401.
Drs. Conant and Schnall: Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1 Silverstein, 3400 Spruce Street, Philadelphia, PA 19104.
Drs. Onega and Tosteson: The Dartmouth Institute for Health Policy and Clinical Practice, Geisel School of Medicine at Dartmouth, 1 Medical Center Drive (HB7505), Lebanon, NH 03756.
Mr. Garcia: Fred Hutchinson Cancer Research Center, M3-C102, 1100 Fairview Avenue North, Seattle, WA 98109.
Dr. Beaber: Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA 98109.
Dr. Herschorn: Department of Radiology, University of Vermont Medical Center, 111 Colchester Avenue, Burlington, VT 05401.
Dr. Lehman: Radiological Associates, Massachusetts General Hospital, 15 Parkman Street, Boston, MA 02114.
Dr. Lacson: Center for Evidence-Based Imaging, Department of Radiology, Brigham and Women's Hospital, 20 Kent Street, Brookline, MA 02445.
Dr. Kontos: Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Room D702, Richards Building, 3700 Hamilton Walk, Philadelphia, PA 19104.
Dr. Haas: Division of General Internal Medicine and Primary Care, Brigham and Women's Hospital, 1620 Tremont Street, Boston, MA 02115.
Dr. Weaver: Department of Pathology, University of Vermont College of Medicine, Given Courtyard, 89 Beaumont Avenue, Burlington, VT 05405-0068.
Dr. Barlow: Cancer Research and Biostatistics, 1730 Minor Avenue, Suite 1900, Seattle, WA 98101.
Author Contributions: Conception and design: B.L. Sprague, E.F. Conant, E.F. Beaber, S.D. Herschorn, C.D. Lehman, M.D. Schnall, J.S. Haas, D.L. Weaver, W.E. Barlow.
Analysis and interpretation of the data: B.L. Sprague, E.F. Conant, T. Onega, M.P. Garcia, E.F. Beaber, S.D. Herschorn, C.D. Lehman, A.N.A. Tosteson, R. Lacson, D. Kontos, D.L. Weaver, W.E. Barlow.
Drafting of the article: B.L. Sprague, E.F. Conant, M.P. Garcia, R. Lacson, J.S. Haas, W.E. Barlow.
Critical revision of the article for important intellectual content: B.L. Sprague, E.F. Conant, T. Onega, M.P. Garcia, E.F. Beaber, S.D. Herschorn, C.D. Lehman, A.N.A. Tosteson, R. Lacson, D. Kontos, J.S. Haas, D.L. Weaver, W.E. Barlow.
Final approval of the article: B.L. Sprague, E.F. Conant, T. Onega, M.P. Garcia, E.F. Beaber, S.D. Herschorn, C.D. Lehman, A.N.A. Tosteson, R. Lacson, M.D. Schnall, D. Kontos, J.S. Haas, D.L. Weaver, W.E. Barlow.
Provision of study materials or patients: E.F. Conant, T. Onega, J.S. Haas.
Statistical expertise: M.P. Garcia, R. Lacson, W.E. Barlow.
Obtaining of funding: B.L. Sprague, E.F. Conant, T. Onega, A.N.A. Tosteson, M.D. Schnall, D. Kontos, J.S. Haas, D.L. Weaver, W.E. Barlow.
Administrative, technical, or logistic support: M.D. Schnall, J.S. Haas, D.L. Weaver.
Collection and assembly of data: B.L. Sprague, E.F. Conant, T. Onega, M.P. Garcia, S.D. Herschorn, R. Lacson, J.S. Haas, D.L. Weaver, W.E. Barlow.
This article was published at www.annals.org on 19 July 2016.
* For a list of PROSPR investigators and research staff, see the Appendix.

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Brian L. Sprague, Emily F. Conant, Tracy Onega, et al; on behalf of the PROSPR Consortium . Variation in Mammographic Breast Density Assessments Among Radiologists in Clinical Practice: A Multicenter Observational Study. Ann Intern Med.2016;165:457-464. [Epub 19 July 2016]. doi:10.7326/M15-2934

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