Case 57 Answer
A persistent focal asymmetry is present in the UOQ. However, it is still not definitely a mass from these images. There is no architectural distortion and no associated calcifications.
Whenever you have this scenario (persistent FA), you always need to perform an ultrasound before making your final assessment:
If it is a cyst the same size as the FA, it is benign.
If it is a definite solid mass at US, then it is suspicious.
If you see nothing but fibroglandular tissue, then this qualifies as Probably Benign. That is, the FA is persistent, but it is likely just breast tissue.
In this case, an ultrasound was performed, and no abnormality was found. Would old films make a difference?