This study will provide a better knowledge of the expected outcome of immediate breast reconstruction, when it is performed by one of these two surgical techniques. The investigators expect that these results will help determine if the prepectoral implant placement may represent a better and gentler method for reconstruction of the breast with lower morbidity than the retropectoral implant placement. In all cases the results of this trial will enable us to provide our patients with better and more objective information, before they are subjected to immediate breast reconstruction.