Is it a good practice to request previous imaging, including Mammograms (MG), Ultrasounds (US), and Magnetic Resonance Imaging (MRI), when analyzing a possible breast cancer imaging?

Requesting Previous Imaging for Breast Cancer Analysis

Yes, it is absolutely essential to request previous imaging when analyzing a possible breast cancer case, as this practice significantly improves diagnostic accuracy and reduces unnecessary biopsies.

Benefits of Comparing with Prior Images

• Radiologists should always attempt to obtain previous mammograms when evaluating abnormal findings, particularly for lesions that are of low suspicion mammographically 1
• When a finding requires additional evaluation (BI-RADS category 0), comparison with previous studies is crucial whenever possible 1
• The American College of Radiology (ACR) explicitly recommends that radiologists use judgment on how vigorously to attempt obtaining previous studies 1
• Comparison with prior images is especially important for distinguishing between scarring and recurrence in patients with breast cancer treated with lumpectomy and radiation therapy 1

Impact on Diagnostic Performance

• Comparison with prior mammograms can help determine if a questionable area is clearly benign, potentially avoiding unnecessary diagnostic mammograms 1
• For BI-RADS category 0 findings (incomplete assessment), comparison with previous mammograms is a key component of proper evaluation 1
• Prior images are particularly valuable when evaluating patients with a personal history of breast cancer, as they help differentiate post-surgical changes from recurrence 1
• Studies show that radiologists achieve higher specificity (ability to correctly identify normal cases) when reading mammograms with prior images from the same vendor (78.7%) compared to cases without prior images (74.9%) 2

Clinical Scenarios Requiring Prior Images

• For patients with a history of breast cancer treated with lumpectomy, prior images are essential for distinguishing between post-treatment changes and recurrence 1
• When evaluating response to neoadjuvant chemotherapy, comparison with pre-treatment imaging is critical for accurate assessment 1
• In cases of suspected local recurrence, comparison with baseline post-treatment imaging is necessary 1
• For patients with dense breasts or complex findings, comparison with prior studies helps determine stability or change over time 1

Limitations and Caveats

• While prior images are valuable, sensitivity for cancer detection may sometimes be higher when reading without prior images (80.3% vs. 71.2% with same-vendor priors) 2
• Radiologists should not delay urgent evaluation if prior images cannot be obtained in a timely manner 1
• The benefit of prior images varies based on lesion characteristics - architectural distortions and abnormal calcifications are more likely to be correctly identified when comparing with different-vendor prior images 2
• For high-risk patients requiring MRI screening, comparison with prior MRI studies is particularly important due to the higher false-positive rate of MRI 1

Best Practices for Image Comparison

• Request all relevant prior imaging modalities, including mammograms, ultrasound, and MRI when available 1
• For patients with breast implants or lobular cancers, comparison with prior MRI is especially valuable 1
• When evaluating response to neoadjuvant therapy, obtaining pre-treatment MRI for comparison is essential 1
• For patients with a personal history of breast cancer, comparison with prior images should be standard practice to detect recurrence at the earliest possible stage 1