Focal asymmetry can be one of many things discovered in the breast tissue, many of which are NOT cancer. It's always best to get a clear picture as to what is going on so I'm sure the 3D Mammo and Ultrasound will clear this up as they will be focused on the area of concern giving the best and detailed information. If there is still some question about the cause a biopsy may be suggested in the future. Please let us know your results after these latest tests and if you have any further concerns we will be here to help as best we are able. Take care and proceed with the additional testing as recommended. Regards .....