Are biopsies ever wrong? Fibroadenoma vs Phyllodes

[clmlw]

I have a hard lump in my left breast. It started out the size of a pea 3 months ago. It is now the size of a walnut. I've been through the whole mammogram & ultrasound thing. I had a core biopsy done last week, and the results indicate it is probably a fibroadenoma. But last week, they thought it was a benign phyllodes. My questions:

-How often is a biopsy wrong? In other words, if the biopsy indicates that it's a fibroadenoma, what are the chances of it turning out to be a phyllodes tumor?

-Do they take a margin on a fibroadenoma or just on a phyllodes?

-Is there an increased risk of cancer after having a fibroadenoma?


Thanks in advance :) Christy

[Twocapes]

I had seven fibroadenomas removed in the past 25 years and the eighth lump was positive for cancer.  Fibroadenomas do not "turn" into cancerous lesions.  The risk with having fibroadenomas is ignoring a new lump figuring it is just the same thing.  Also, if left in, it could get in the way of other lumps during self examinations.  Ironically when they removed my cancerous lump (I elected to have a lumpectomy), there was also a fibroadenoma in the tissue they took.

[clmlw]

Thank you so much, and yes, it was called a cellular fibroadenoma - too funny. I'm meeting with a breast oncology surgeon next week to schedule surgery. Do you know if a general or local anesthesia is used for removal? Personally, I know the risks of general, and I'd much rather take my chances than be awake while they remove it.

[Computer_Voice]

The fact that it's growing so quickly makes phyllodes somewhat likely.  It's sometimes very hard for the pathologist to distinguish between a phyllodes and a fibroadenoma when only a core biopsy has been performed and they are often misdiagnosed.  Did they call it a "cellular" fibroadenoma, which can be interpreted as code for I can't really tell if it's a fibroadenoma or a phyllodes?  They don't usually try to take margins on a fibroadenoma, just try to shell it out as best as possible.  The fact that it's growing so quickly makes it worth taking out.  Even if it is just a fibroadenoma, with that rate of growth the earlier the surgery the smaller it will have to be.  Benign phyllodes tumors are on a continuum with malignant phyllodes tumors.  Malignant phyllodes often recur locally and rarely metastasize, but when they do it typically bypasses the lymph nodes.  Anyway, it's certainly nothing to worry about and if you watch it for another several months to see if it stays on that same growth trajectory or stabilizes you won't be risking anything, except perhaps a slightly larger incision.  The dogma is that fibroadenoma's do not turn into cancer and do not increase the risk of cancer.  The statistical reality is that they do increase the risk of cancer ever so slightly (as do a million other things) when you do the math, but not enought that it should be considered a risk factor or removed for that reason.