Skip to content
My WebMD Sign In, Sign Up

Breast Cancer Health Center

Font Size

Breast Cancer Screening (PDQ®): Screening - Health Professional Information [NCI] - Mammography—Variables Associated with Accuracy

Patient Characteristics

Several characteristics of women being screened that are associated with the accuracy of mammography include age, breast density, whether it is the first or subsequent exam, and time since last mammogram. Younger women have lower sensitivity and higher false-positive rates on screening mammography than do older women (refer to the Breast Cancer Surveillance Consortium performance measures by age for more information).

Recommended Related to Breast Cancer

About This PDQ Summary

Purpose of This Summary This PDQ cancer information summary for health professionals provides comprehensive, peer-reviewed, evidence-based information about the treatment of male breast cancer. It is intended as a resource to inform and assist clinicians who care for cancer patients. It does not provide formal guidelines or recommendations for making health care decisions. Reviewers and Updates This summary is reviewed regularly and updated as necessary by the PDQ Adult Treatment Editorial...

Read the About This PDQ Summary article > >

For women of all ages, high breast density is associated with 10% to 29% lower sensitivity.[1] High breast density is an inherent trait, which can be familial [2,3] but also may be affected by age, endogenous [4] and exogenous [5,6] hormones,[7] selective estrogen receptor modulators such as tamoxifen,[8] and diet.[9] Hormone therapy is associated with increased breast density and is associated not only with lower sensitivity but also with an increased rate of interval cancers.[10]

The Million Women Study in the United Kingdom revealed three patient characteristics that were associated with decreased sensitivity and specificity of screening mammograms in women aged 50 to 64 years: use of postmenopausal hormone therapy, prior breast surgery, and body mass index below 25.[11] In addition, a longer interval since the last mammogram increases sensitivity, recall rate, and cancer detection rate and decreases specificity.[12]

Strategies have been proposed to improve mammographic sensitivity by altering diet, timing mammograms with menstrual cycles, interrupting hormone therapy before the examination, or using digital mammography machines.[13] Obese women have more than a 20% increased risk of having false-positive mammography results compared with underweight and normal weight women, although sensitivity is unchanged.[14]

Tumor Characteristics

Some cancers are more easily detected by mammography than other cancers are. In particular, mucinous, lobular, and rapidly growing cancers can be missed because their appearance on x-rays is similar to that of normal breast tissue.[15] Medullary carcinomas may be similarly missed.[16] Some cancers, particularly those associated with BRCA 1/2 mutations, masquerade as benign tumors.[17,18]

Physician Characteristics

Radiologist performance is critical to assessing mammographic interpretive performance, yet there is substantial, well-documented variability among radiologists. Factors that influence radiologists' performance include their level of experience and the volume of mammograms they interpret.[19] There is often a trade-off between sensitivity and specificity, such that higher sensitivity may be associated with lower specificity. Radiologists in academic settings have a higher positive predictive value (PPV) of their recommendations to undergo biopsy than do community radiologists.[20] Fellowship training in breast imaging may lead to improved cancer detection, but it is associated with higher false-positive rates.[13]

Facility Characteristics

After controlling for patient and radiologist characteristics, screening mammography interpretive performance (specificity, PPV, area under the curve [AUC]) varies by facility and is associated with facility-level characteristics. Higher interpretive accuracy of screening mammography was seen at facilities that offered screening examinations alone, included a breast imaging specialist on staff, did single as opposed to double readings, and reviewed interpretive audits two or more times each year.[21]

1|2|3|4

WebMD Public Information from the National Cancer Institute

Last Updated: February 25, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
Next Article:

Today on WebMD

Breast Cancer Overview
From self-exams and biopsies to reconstruction, we’ve got you covered.
Dealing with breast cancer
Get answers to your questions.
 
woman having mammogram
Experts don’t agree on all fronts, but you can be your own advocate.
woman undergoing breast cancer test
Many women worry. But the truth? Most abnormalities aren’t breast cancer.
 
Breast Cancer Treatments Improving
VIDEO
Resolved To Quit Smoking
SLIDESHOW
 
Woman getting mammogram
Article
Screening Tests for Women
SLIDESHOW
 
ovarian cancer overview slideshow
SLIDESHOW
serious woman
Article
 
what is your cancer risk
HEALTH CHECK
10 Ways to Revitalize Slideshow
SLIDESHOW