Received a BI-RADS 4C result? Learn what high suspicion means, why a biopsy is strongly recommended, and why BI-RADS 4C is still not a confirmed cancer diagnosis.
BI-RADS 4C Explained: What Does High Suspicion Mean?
Receiving a BI-RADS 4C result can be frightening.
Many patients immediately wonder:
“Does BI-RADS 4C mean I have breast cancer?”
The answer is no—not yet.
BI-RADS 4C means that the imaging finding has a high level of suspicion for malignancy, but it is not a confirmed cancer diagnosis.
A biopsy is needed to determine exactly what the lesion is.
What Is BI-RADS 4C?
BI-RADS 4 is divided into three subcategories:
4A — Low suspicion
4B — Moderate suspicion
4C — High suspicion
BI-RADS 4C is the most suspicious category within BI-RADS 4.
According to the BI-RADS framework, the likelihood of malignancy for category 4C is greater than 50% but less than 95%.
This is why tissue diagnosis is strongly recommended.
Why Is a Biopsy Necessary?
Ultrasound and mammography can identify features associated with breast cancer, but imaging alone cannot provide a definitive diagnosis.
A biopsy allows a small amount of tissue to be examined under a microscope.
This determines whether the finding is benign or malignant.
What Ultrasound Features May Raise Suspicion?
Depending on the lesion, suspicious features may include:
✔ Irregular shape
✔ Spiculated or indistinct margins
✔ Non-parallel orientation
✔ Posterior acoustic shadowing
✔ Architectural distortion
✔ Other suspicious associated findings
However, no single ultrasound feature alone proves that a lesion is cancer.
The entire imaging appearance and clinical situation must be considered.
Is BI-RADS 4C the Same as BI-RADS 5?
No.
This is an important distinction.
BI-RADS 4C means there is a high suspicion of malignancy and biopsy is recommended.
BI-RADS 5 is reserved for findings that are highly suggestive of malignancy, with an estimated likelihood of malignancy of at least 95%.
Therefore, BI-RADS 4C is concerning, but it is still not the same category as BI-RADS 5.
A Sonographer’s Perspective
One question patients often ask is:
“Can you tell from the ultrasound whether it’s definitely cancer?”
Ultrasound can tell us how suspicious a lesion looks.
But it cannot replace pathology.
The biopsy result provides the definitive diagnosis.
Key Takeaways
✔ BI-RADS 4C means high suspicion for malignancy.
✔ It does not mean breast cancer has already been confirmed.
✔ Biopsy is strongly recommended.
✔ BI-RADS 4C is more suspicious than 4A and 4B.
✔ BI-RADS 5 represents an even higher level of suspicion.
