From the Guidelines
For patients with dense breasts, additional screening beyond standard mammography is recommended to improve cancer detection and reduce morbidity and mortality. If you have dense breasts, you should discuss with your healthcare provider about supplementing your annual mammogram with breast ultrasound or MRI for better cancer detection 1. Even with negative imaging results, any palpable breast abnormality should be evaluated with a biopsy, as 10-15% of breast cancers aren't detected by imaging alone. Dense breast tissue not only makes it harder to see small masses on mammograms but also represents an independent risk factor for developing breast cancer. The additional tissue density can hide cancerous lesions on standard mammography, which is why the supplemental imaging is valuable. Some key points to consider include:
- The sensitivity of mammography can vary significantly with breast density, with sensitivity as low as 30% in women with dense breast tissue 1.
- Supplemental screening options, such as digital breast tomosynthesis (DBT), whole-breast ultrasound (WBUS), and MRI, may detect additional breast cancer, but also result in a higher number of false-positive results 2, 3, 4, 5.
- Clinical examination findings should always take precedence over imaging results when there's a discrepancy, and a concerning physical finding warrants further investigation regardless of normal imaging. Remember, the goal of screening is to reduce breast cancer morbidity and mortality, and improve quality of life, and supplemental imaging in patients with dense breasts can help achieve this goal 1.
From the Research
Recommendations for Women with Dense Breasts
- Women with dense breasts have a modestly increased risk of breast cancer and experience reduced sensitivity of mammography to detect breast cancer 6.
- Supplemental screening with breast ultrasound or breast MRI may be of value in these patients, as it can increase breast cancer detection 7, 8.
- A negative mammogram or other imaging report should not preclude further evaluation, which could include biopsy of a palpable abnormality.
Diagnostic Performance of Imaging Modalities
- Magnetic Resonance Imaging (MRI) has the highest sensitivity for breast cancer detection, regardless of breast type, density, and history 9.
- Mammography has the lowest sensitivity, while ultrasound has a moderate sensitivity 9.
- Combining imaging modalities, such as MRI + ultrasound or MRI + mammography, can increase diagnostic ability compared to using modalities alone 9.
Supplemental Screening Techniques
- Abbreviated MRI and contrast-enhanced mammography have been shown to detect more invasive cancers compared to automated whole breast ultrasound (ABUS) 8.
- Contrast-enhanced mammography can be a viable option in dense breast tissue when there are contraindications to MRI, as it also has high sensitivity based on the type of breast cancer 9.
Clinical Guidance
- Healthcare providers should comply with state laws that require disclosure to women of their breast density as recorded in a mammogram report 6.
- Standardizing recommendations and implementation of risk-based decision-making using a validated calculator can allow for earlier detection of breast cancer and ensure equitable care for patients 7.