This is a great question and deserves a detailed answer. The breast reconstruction that is made up of an implant or abdominal tissue cannot develop breast cancer because it does not contain breast tissue. However, even with the best mastectomy there is always some breast tissue that is left behind. Therefore, there is a chance that the breast tissue that is left in the breast surround the reconstruction can develop a new breast cancer or recurrent breast cancer. The risk of this is generally extremely small, but will depend on the size and grade of the initial breast tumour, radiation status and of course the completeness of the mastectomy.