BI-RADS 5 Fibroadenoma?

DeeDeeT405

New here. My mammogram/US were done because I had found a dimpled area under my right breast when I raised my right arm. My report said “abnormality 9:00 position 5cm from the nipple there is a hypoechoic irregularly shaped spiculated mass measuring 1 x 1.8 x 1.4 cm. My BI-RADS score was 5. 2 radiologists reviewed the results and agreed. I was sent for an ultrasound guided core biopsy last Wednesday. Today I got the results and was told she was “very shocked” that it came back as a Fibroadenoma. She even went back and talked with the radiologists and reviewed the mammogram and US images again. I have an appointment with the breast surgeon next week.

My question is- is this a common finding that it would only be a Fibroadenoma with those imaging results

Beesie

On ultrasound imaging, a fibroadenoma is usually a well-circumscribed oval mass, which is pretty much the opposite of an irregularly shaped spiculated mass.

This is why the biopsy finding of a fibroadenoma is surprising. When biopsy results aren't consistent with what would be expected from the imaging, the results are considered discordant. When this happens, usually an excisional (i.e. surgical) biopsy is recommended, to remove the entire suspicious mass for a more complete examination under the microscope. I'm guessing this is why you've been referred to the Breast Surgeon.

Hopefully this does end up being just a benign fibroadenoma; I don't know how likely that is with that appearance on the imaging. Another possibility - not as good for you - is something I've seen just a few times in my many years on this site, which is that an area of cancer grows within a fibroadenoma. The fibroadenoma itself is benign, but it is composed of the same components as breast tissue (well, that's my simplistic layperson's understanding) so just as breast cancer can develop in breast tissue, it can develop within a fibroadenoma. That might not be what's happened in your case, but it's a possible explanation.

Please let us know what the Breast Surgeon says.

DeeDeeT405

I agree with everything you’ve said. With the BIRADS 5 and shape of the mass, I already was prepared that this was indeed cancer. The biopsy results don’t ease my fears at all and we’re left wondering if they evensampled the right area.