Dear cassandraw30: What this means is that both tests are highly suspicious that this is cancer. We do not know yet, the full scope of the problem. Your mother will need to see a breast surgeon along with an oncologist who can come up with the best plan for treatment. It is not too late, necessarily but time should not be wasted in getting treatment started.
As an asside, I do hope that you will be sure to get regular screening mammograms for yourself.
the level 5 thing means it's likely to be cancer, but not that it's gone too far. That only is determined after testing the tumor, lymph nodes, etc. But no matter what size or stage a tumor is in there are various treatments available which can result in anything from cure to long term (many years) control. At this point there's no way to know for sure what to expect, but the answers will be coming in. Many tumors that get very large within the breast don't spread to other organs. So even very large tumors may be curable, depending on the situation.