Although, you have an acceptable reconstruction, you may benefit from a shaping and symmetry procedure.
Unfortunately, the location of the scar is dictated by the type of mastectomy performed. This is based on the amount of skin removal necessary to treat your cancer and the preference of your mastectomy surgeon.
There is little that can be done to erase these scars. In reconstruction and body contouring, we have to trade off scarring for shape, size, and symmetry. If you are interested in downsizing your breasts, a portion of the flap skin and tissue could be removed, but this will not change the position of the upper mastectomy scars.
I wish you all the best!!
Web reference: http://www.drpaulgill.com