What is the difference between a mammogram and a breast ultrasound?

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1. 1

   Breast imaging (Wikipedia)

   WikipediaPublished Sep 29, 2026Checked Oct 17, 2026

   “In medicine, breast imaging is a sub-speciality of diagnostic radiology that involves imaging of the breasts for screening or diagnostic purposes. There are various methods of breast imaging using a variety of technologies as described in detail below. Traditional screening and diagnostic mammography ("2D mammography") uses x-ray technology and has been the mainstay of breast imaging for many decades. Breast tomosynthesis ("3D mammography") is a relatively new digital x-ray mammography technique that produces multiple image slices of the breast similar to, but distinct from, computed tomography (CT). Xeromammography and galactography are somewhat outdated technologies that also use x-ray technology and are now used infrequently in the detection of breast cancer. Breast ultrasound is another technology employed in diagnosis and screening that can help differentiate between fluid filled and solid lesions, an important factor to determine if a lesion may be cancerous. Breast MRI is a technology typically reserved for high-risk patients and patients recently diagnosed with breast cancer.”

2. 2

   Bridging the gap: clinical practice, guidelines, reimbursement and real-world challenges in breast imaging - webinar highlights.

   Future oncology (London, England) (Reis et al.)Published Jul 22, 2026Checked Oct 17, 2026

   “Breast cancer is a leading cause of cancer-related mortality globally. Mammographic breast density is an identified independent risk factor to develop breast cancer. Nationwide breast cancer screening programs, which typically utilize X-ray mammography, decrease breast cancer-related deaths; however, breast density limits breast cancer detection on a mammogram. Contrast-enhanced breast imaging modalities such as magnetic resonance imaging (MRI) and the newer contrast-enhanced mammography (CEM), have utility to improve early breast cancer detection. This report summarizes discussions held during the webinar, "Bridging the Gap: Clinical Practice, Guidelines, Reimbursement and Real-World Challenges in Breast Imaging." Experts from the United States and Europe examined critical aspects of breast MRI and CEM, focusing on the implementation of existing guidelines, payor policies, and barriers to their adoption. The conversation highlighted how these challenges affect broader implementation, reimbursement issues, the alignment of guidelines with payors, and patient dynamics.”

3. 3

   Supplemental Breast Ultrasound in Mammography Screening for Women with Critically Dense Breasts.

   Cancers (Heywang-Köbrunner et al.)Published May 19, 2026Checked Oct 17, 2026

   “From May 2020 to March 2024, 25,341 women underwent MXUS, while 38,529 received MX-only. The CDR was significantly higher in the MXUS group, at 10.7 per 1000 (95% CI: 9.4-12.0) compared to 7.2 per 1000 (95% CI: 6.4-8.1) in the MX-only group, yielding an incremental CDR of 3.5 per 1000 (95% CI: 1.9-5.0). However, MXUS led to higher rates of recall (6.6% vs. 5.4%), biopsies (3.2% vs. 1.5%), and short-term follow-up recommendations (0.9% vs. 0.5%). Implementing quality-assured S-US for women with critically dense breasts substantially increases the detection of invasive cancers, but also raises false positives. While these results support density-adapted screening, the high resource intensity suggests that future strategies should optimize risk stratification to target S-US more selectively. Long-term data are required to confirm clinical benefits.”

4. 4

   Incremental Cancer Detection and False-Positive Burden of Screening Ultrasound After Negative Digital Breast Tomosynthesis: A 10-Year, 100,000-Examination Retrospective Study.

   Academic radiology (Dodelzon et al.)Published Jul 15, 2026Checked Oct 17, 2026

   “Subgroup analyses were performed by age and breast density.ResultsAmong 102,993 concurrent screening examinations, 6647 (6.5%) had negative DBT but abnormal ultrasound assessment. This cohort yielded 99 cancers, corresponding to an incremental ultrasound CDR of 1.0 per 1000 screened and PPV1 of 1.5%. The false-positive rate of screening ultrasound was 98.5%. Among 1917 resulting biopsies, 99 were malignant (PPV3 5.2%; false-positive biopsy rate of 94.8%), the majority of which were invasive histologic type (89/99, 89.9%). Cancer detection did not differ significantly by breast density, while false positives increased with age (OR 1.05, p ConclusionIn the DBT era, screening ultrasound after negative mammography provides a modest increase in cancer detection at the cost of high false-positive and biopsy rates. These findings support a shift toward risk-based screening strategies and greater reliance on vascular-based modalities such as MRI or contrast-enhanced mammography (CEM) for supplemental screening in women with dense breasts.”

5. 5

   BI-RADS (Wikipedia)

   WikipediaPublished Oct 7, 2026Checked Oct 17, 2026

   “The Breast Imaging-Reporting and Data System (BI-RADS) is a quality assurance tool originally designed for use with mammography. The system is a collaborative effort of many health groups but is published and trademarked by the American College of Radiology (ACR). The system is designed to standardize reporting and is used by medical professionals to communicate a patient's risk of developing breast cancer, particularly for patients with dense breast tissue. The document focuses on patient reports used by medical professionals, not "lay reports" that are provided to patients.”