Dear Rosy, Fat necrosis is a firm, round lump that forms in an area of fatty breast tissue that has been damaged. This may be from previous surgery to the breast or a bruise or injury to the breast (although many women may not remember any specific injury). The lump is usually painless, and the skin around it may look red, bruised or dimpled. Findings from scans (mammogram, ultrasound) can be suspicious for this. Sometimes an MRI might also be done to further evaluate. These findings can be more or less suspicious but definite diagnosis would be through biopsy.
I'd disagree a bit: it's not typically round, and may not be feelable. Certain patterns show on xray and can be assumed to be fat necrosis; but it's not possible to tell with certainty by mammogram alone. In fact, it's one thing that can sometimes look a lot like cancer on xray, and more often than not leads to biopsy before one can be absolutely sure. In the cases I've seen, I'd not rely on xray interpretation alone. I'd defer to a radiologist on the issue as to whether MRI could indeed be definitive. In general, I'd say a stereotactic, or other biopsy would be needed. However, not seeing the xray, I'm sure it's possible to see certain shadows and be comfortable it's ok, even if fat necrosis is on the list of possibilities.
I guess I should add this: the pattern of calcifications might indeed indicate benign. One way this is so is with a degenerated fibroadenoma, which often calcifies in a particular way. Likewise, whereas it may or may not be certain that the area is fat necrosis, if it has large dense calcifications in it, it would in fact be pretty confidently benign.
Fat necrosis can be any shape or form, as mine was. I had a lobulated mass, quite large (3cmx2.5 cm), near my armpit removed in February that pathology deemed fat necrosis and reactive lymph nodes. Fat necrosis can cause an inflammatory response, thus enlarging nodes. I had a breast reduction two years ago, and although I never smoked in my life, developed areas of fat necrosis...probably from exercising too soon after surgery. Women
who are very large busted can form areas of necrosis as well, without any known trauma to the breast. Unfortunately, unless very obvious on mammo/ultrasound, fat necrosis can mimic carcinoma, and biopsy is the only sure way to confirm, however, it sounds like your radiologist was able to make a definitive call based on the ultrsound, which is great.
My 15 year old daughter has a large mass in her right breast. She has had it for several months but just informed me of it last week. I took her to family dr. and he said she needed a mammogram. I called a local breast screening clinic and they told me absolutely not, that at her age the breasts are too dense, and she should have an ultrasound, which she will be having in a couple of weeks. She did have a very severe trauma to that breast last year in gym class. Another student dropped a 20 lb weight on her (my daughter was laying on floor and this girl went to jump over her and dropped the weight on her breast. I am just hearing about this now for some reason. Anyways, I don't believe she had the lump before this, from what I can gather from her, and it has gotten larger over time, could this be from the trauma, I have read about fat necrosis and scar tissue. The lump is very palpable, quite large, easily moveable, firm, not round, more flat and irregular feeling. Any insight would be appreciated. Oh yes, also, if it is fat necrosis what do they do?
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