Hi,You are right,there is NO stage 5 breast cancer...what your friend might have heard is that her BIRADS score is a 5...(.BIRADS are used by radiologist to categorize the imagery seen on mammograms and they give a score from 1 to 5.A score of five means that the lesion seen in the mammogram or ultrasound ,is highly suspicious of malignancy..but a biopsy is the only test that will give an accurate diagnosis.As Versh mentioned the breast cancer stage goes only up to 4.Best wishes to your friend and you.
I have only heard of stage 4. the next they call the last stage.