After mastectomy, breast reconstruction restores breast contour, volume and symmetry. Reconstruction can be performed any time after mastectomy, although it most commonly is performed immediately after the mastectomy during the same surgery by placing a special type of breast implant called a tissue expander. This is followed by replacing the expander with a permanent implant after several weeks. Alternatively, reconstruction can be performed by using tissue from the back or abdomen, with or without an implant.