Second Biopsy recommended

[Cat Crazy]

I had my first screening mammogram at age 48 in April of this year. Calcifications were found behind my left nipple. The report from the magnified mammagram classified them as clustered and heterogenous and category "4" suspicious. Surgical consult recommended. A stereotactic biopsy result was "Fibrocystic change with focal atypical lobular hyperplasia." Rec: Due to the presence of atypia, surgical consultation for wide excision following wire localization. Apx nine samples were removed but some calcifications do remain.
If stereotactic biopsies are over 95% accurate, why should I go through the pain and expense of another procedure? My physician and the surgeon she recommended, both act as if I'm nuts to question the necessity of a second biopsy. I prefer a follow up mammagram in October and see if anything has changed. Am I over rationalizing as my doctor suggested?
Lastly, what other "clinical reasons" would be present for a second biopsy?
Additional Info:I'm adopted so I have no family history available. I weigh 100lbs (small woman/small breasts)
I've read of women that go through repeated biopsies and I don't want to be left with damaged tissue that doesn't mammagram well in the future.
Thank you for a wonderful forum and website.

[surgeon]

atypia means a form of abnormality than can be seen with lots of conditions. The concern is that where there is atypica, it's possible there is also cancer nearby. So it's a matter of how much of the tissue needs sampling to be sure. If lots of the calcifications were seen in the specimens taken, it's probably a pretty accurate sample. However, we tend to want to err on the side of being too cautious: what's the worse error: assuming things are ok when they aren't, or doing an extra surgery and finding out it is ok?

[CCF-RN,MSN-rf]

Dear Cat Crazy:  The concern with any biopsy that only removes a portion of tissue is that there could be tissue left behind that may yield different results.  Most physicians will err on the side of safety by making certain that nothing is left to chance.  In your case, with remaining calcifications the concern is that there could be cancerous cells that were not identified in the biopsy.  By removing the whole area, one can be certain that nothing suspicious has been left behind.  It is certainly your choice on how to proceed.  Until time passes, no one will know which choice is right.