I install and service Mammography equipment. I'm a guy, but saw the thread title and thought I may be able to offer some info.
New digital Mammo systems are very good at imaging the tiniest of calcifications. Implants are not a problem. Your imaging tech should ask about them, if not be sure to mention it. There are specific techniques for implants. The implants will be clearly visible on the image.
I also service Radiation Therapy equipment so I may be able to answer questions about that.
Hope your MIL is doing well.