A mammogram is an x-ray exam of the breast that is used to detect and evaluate breast changes.
X-rays were first used to examine breast tissue a century ago, by the German surgeon, Albert Salomon. Modern mammography has only existed since the late 1960s, when special x-ray machines were designed and used just for breast imaging. Since then, the technology has advanced, and today’s mammogram is very different even from those of the 1980s and 1990s.
The x-ray machines used for mammograms today expose the breast to much less radiation than those used in the past. The x-rays do not go through tissue as easily as those used for routine chest x-rays or x-rays of the arms or legs, which also improves the image quality.
Understanding your mammogram report – BI-RADS categories
The American College of Radiology (ACR) came up with a standard way to describe mammogram findings and results. In this system, the results are sorted into categories numbered 0 through 6. This system is called the Breast Imaging Reporting and Data System (BI-RADS).
BI-RADS 0: Additional imaging evaluation and/or comparison to prior mammograms is needed.
BI-RADS 1: Negative There’s no significant abnormality to report.
BI-RADS 2: Benign (non-cancerous) finding: This is also a negative mammogram result.
BI-RADS 3: Probably benign finding – Follow-up in a short time frame is suggested
The findings in this category have a very high chance (greater than 98%) of being benign (not cancer).
BI-RADS 4: Suspicious abnormality – Biopsy should be considered
Findings do not definitely look like cancer but could be cancer.
BI-RADS 5: Highly suggestive of malignancy – Appropriate action should be taken
The findings look like cancer and have a high chance (at least 95%) of being cancer. Biopsy is very strongly recommended.
BI-RADS 6: Known biopsy-proven malignancy – Appropriate action should be taken
This category is only used for findings on a mammogram that have already been shown to be cancer by a previous biopsy. Mammograms may be used in this way to see how well the cancer is responding to treatment.