Yes,I had a stereotactic breast core biopsy to test some calcifications found in my breast. Now.. you ask is it painful?? Well..I would not exactly call it pain. Let's just say.. it sort of felt something that more resembled a "sting", whenever the procedure was being done. There is a needle which is placed in the breast(which is of course anesthetized!).Through the use of some very high tech machine and looking at the mammo which had shown where it(area to be biopsied ) is, the procedure is done. Looking at the pics. as u are on the table, sort of tells the dr. that she/he is in the right area. With the press of some buttons, they procede to sort of "suction out" the tiny specs that they felt needed biopsying. It is an incredibly wonderful system, and I would suspect much better than having a real surgical biopsy. You lie on a table and it is done as you face down. The dr. works under the table..(which I can't imagine being too comfortable!). When it is over, a bandaid is placed over the tiny punctured area.. and you go home!! I'd be happpy to give you more "details" just email good luck!!