@Tart Cherry Jam - I've never had an MRI instead of the yearly mammogram, but this year, after my annual mammogram, I too had to have a diagnostic mammogram & ultrasound for one of my breasts. The diagnostic mammogram showed dense breast tissue and had an abnormality on it and the US afterward showed it was likely a variation on the normal breast tissue due to dense breast tissue (though the annual mammogram said I didn't have dense breast tissue?). At any rate, I have to follow up with a mammogram at 6 mo. instead of 1 yr but no biopsy or anything else needed right now. Hopefully the same is true for you. I had an abnormal mammogram a long, long time back, and the same thing happened then too except I think it was a cyst that time round. I don't have a family history of breast cancer though.