excisional biopsy

I am going in for an excisional biopsy on Friday.  Since I have no palpable lump (I have ADH/LCIS, columnar cell changes that were found on stereo biopsy), how will they know what to remove? I have a "clip" that was inserted in my breast during the stereo biopsy, so I assume that "tells" the surgeon where to operate.  Can anyone tell me how much tissue needs to be removed in this type of surgery?  Thank you.

[japdip]

You are correct about the purpose of the titanium chip ... this will be the guide unless you are to be having a wire insertion just prior to surgery. This is often done in Radiology immediately prior to going to the OR. As to the amount of tissue to be removed; it depends on the size of the area of suspicion. Clean margins must be obtained and this will be determined when the Pathology examination is done.   Regards ....