You may have already had your biopsy already. So this may be too late. First of all, a birads 3 is 98% benign. A birads 4 is very broad but is on the average 80% benign. So a birads 3.5 (which doesn't exist) means your calcs are about 80 to 98% benign. A stereotactic biopsy is an outpatient core needle biopsy. You lay flat on your stomach with your breast hanging through an opening. A mammogram is done while youre lying down. The calcs are found and the info is sent to a computer. The computer tells the radiologist exactly where to go with the needle.
The limitation is that if the calcs are really deep or near your chest wall, that area may not be able to be localized with the compression paddle. Also, the core biopsy needle has to go through the calcs because the cutting chamber is along the side of the needle near the tip. If your breast tissue is too thin, the needle would have to go through the calcs, which means it may go through the other side of the breast and therefore, the metal compression paddle on the other side. So, this would be impossible to do. There are a few tricks to try to thicken the breast compression, but it doesn't always work.
If they can't do the stereotactic biopsy, you will have an option to either do a 6 month follow up mammogram or do a needle localization surgical excisional biopsy, depending on how suspicious the calcs look and how you feel about it. The needle loc is the traditional way they used to sample calcs before the stereo was invented. A needle and wire are placed through the calcs while you're in compression, and the surgeon uses the wire tip as a guide to surgically remove the lump around the needle tip and also the calcs. It's a fairly simple procedure but the surgeon has to make an incision and a larger lump is taken out which means more scarring.
I hope your biopsy was benign. Good luck!!