A mammogram is an X-ray imaging test that examines breast health. It’s the most efficient tool to help detect breast cancer, especially at its earliest stage. It can also be used as a follow-up tool when doctors find abnormal masses during a clinical breast exam.
While this test can’t medically diagnose breast cancer, it can help identify anything abnormal. Not all abnormal findings are considered cancerous.
Doctors use the BI-RADS system to place abnormal findings into categories. The categories are from 0 to 6. Oftentimes, women 40 years and older receive scores ranging from 0 to 2, indicating normal results or that abnormal results are benign, or noncancerous. If you receive a score of 3 or above, doctors and radiologists recommend a follow-up visit or a biopsy to determine the next course of action.
A score of 0 indicates an incomplete test. The mammogram images may have been difficult to read or interpret. In some cases, doctors may want to compare these new images with older ones to determine if there’ve been any changes. A BI-RADS score of 0 requires additional tests and images to provide a final assessment.
This score confirms that your mammogram results are negative. A score of 1 shows that there’s no cancer and your breasts are of equal density. However, it’s important to continue having routine screenings.
A BI-RADS score of 2 also shows that your mammogram results are normal. There are no indications of cancer, but the doctor may notice some benign cysts or masses to include in your report. Routine visits are suggested with this score. The note on your report will be used as a comparison for any future findings.
A score of 3 implies that your mammogram results are probably normal, but there’s a 2 percent chance of cancer. In this case, doctors recommend a follow-up visit within six months to prove the findings are benign. You’ll also need to have regular visits until your results improve and any abnormalities have stabilized. Regular visits help avoid multiple and unnecessary biopsies. They also help confirm an early diagnosis if cancer is found.
A category 4 score indicates a suspicious finding or abnormality. In this instance, there is a 20 to 35 percent chance of cancer. To confirm, your doctor will need to perform a biopsy to test a small tissue sample.
This score is split within three additional categories based on the doctor’s level of suspicion:
- 4A. Low suspicion for cancer or malignant findings.
- 4B. Moderate suspicion for cancer or malignant findings.
- 4C. High suspicion for cancerous or malignant findings.
Scoring 5 indicates a high suspicion of cancer. In this instance, there’s at least a 95 percent chance of breast cancer. A biopsy is highly recommended to confirm results and determine the next steps for treatment.
You can only score a 6 after you’ve had a biopsy and received diagnosis of breast cancer. This category and corresponding images used as a comparison show how the cancer is responding to necessary treatment, such as chemotherapy, surgery, or radiation.
BI-RADS can also classify breast density into one of four groups. Dense breasts have less fatty tissue. They’re more likely to develop cancer in comparison with less dense breasts with more fatty tissue.
The four categories of breast density are:
- Mostly fatty. Breasts are made up of mostly fat with little fibrous and glandular tissue. A mammogram of breasts with a lower density can more easily show abnormal findings.
- Scattered density. Breasts have a lot of fat with few areas of glandular and fibrous tissue.
- Consistent density. Breasts have an even distribution of fibrous and glandular tissue. This can make it difficult to detect small abnormalities.
- Extremely dense. Breasts have mostly fibrous and glandular tissues, making it difficult to detect cancer. Abnormalities are more likely to blend in with normal breast tissue.
The BI-RADS score helps your doctor communicate your mammogram results and determine treatment. Remember that a BI-RADS score doesn’t provide a diagnosis.
If you receive a higher score that indicates the presence of cancer, you must have a follow-up appointment to confirm your doctor’s findings and to receive a proper diagnosis. An early diagnosis can increase your chances of beating breast cancer.