From the Guidelines
MRI of the breast with contrast has a high negative predictive value for breast cancer, meaning that a negative result is very reliable in ruling out cancer, with a negative predictive value typically exceeding 95%. This high reliability stems from MRI's ability to detect increased blood flow and vascular permeability in tumors through the use of gadolinium-based contrast agents, as seen in studies such as 1. When injected, these agents accumulate in areas with abnormal vascularity, causing cancerous tissues to "light up" or enhance on the images.
Key Points
- The sensitivity of contrast-enhanced MRI for detecting invasive breast cancer is approximately 90-95%, significantly higher than mammography or ultrasound, as reported in 1.
- MRI is most valuable as a supplemental screening tool for high-risk patients or to further evaluate ambiguous findings from other imaging modalities, rather than as a first-line screening test for the general population, as recommended in 1 and 1.
- While a negative MRI is reassuring, it doesn't completely eliminate the possibility of cancer, particularly for very small lesions or certain cancer subtypes that may not enhance significantly, as noted in 1 and 1.
High-Risk Populations
- Studies have shown that MRI screening can be beneficial for women with a genetic predisposition to breast cancer, such as BRCA1 and BRCA2 mutation carriers, as well as those with a strong family history of breast cancer, as seen in 1 and 1.
- Women who have received chest radiation therapy before age 30 may also benefit from annual MRI screening, starting 8-10 years after radiation exposure, as recommended in 1.
Limitations and Considerations
- The specificity of MRI is lower than that of mammography, resulting in more recalls and biopsies, as reported in 1 and 1.
- False-positive results can lead to additional investigations, many of which will not demonstrate that cancer is present, and may cause anxiety and psychological distress, as noted in 1.
From the Research
MRI Breast with Contrast High Negative Predictive Value for Breast Cancer
- The use of MRI with contrast in breast cancer screening has been shown to have a high negative predictive value, meaning that a negative result can effectively rule out the presence of breast cancer 2.
- A study published in 2017 found that the negative predictive value of breast MRI for malignancy was 97.8% among patients who underwent biopsy or had 2 or more years of imaging stability 2.
- Another study published in 2021 compared the performances of ultrasound, mammograms, and MRI in detecting breast cancer in patients with germline pathogenic variants in cancer predisposition genes, and found that MRI presented the highest sensitivity (98.5%) and the lowest underestimation rate (14.5%) in these patients 3.
- The high negative predictive value of MRI with contrast can be useful in screening women at high risk for breast cancer, such as those with BRCA1 or BRCA2 mutations, as it can help to identify those who do not have cancer and reduce the need for unnecessary biopsies and other procedures 4, 5.
- The American College of Radiology recommends that women at high risk for breast cancer undergo annual screening with MRI and mammography, as this can help to detect cancer at an early stage when it is most treatable 6.
Key Findings
- MRI with contrast has a high negative predictive value for breast cancer, making it a useful tool for screening women at high risk.
- MRI is particularly useful in detecting breast cancer in patients with germline pathogenic variants in cancer predisposition genes.
- The combination of MRI and mammography can help to detect breast cancer at an early stage, when it is most treatable.
- Supplemental ultrasound or mammograms may not add significant value to MRI for detecting breast cancer in high-risk patients.