Breast cancer can come back even after a mastectomy. However, the risk of the cancer returning (ie a "recurrence") after a mastectomy is very low and is the same whether you have breast reconstruction or not. Studies have compared patients with similar stage breast cancers and found no difference in recurrence between patients undergoing mastectomy alone (without reconstruction) and those having skin-sparing mastectomy and reconstruction.
When the patient's own tissue is used for the reconstruction (as in a "flap" procedure), only skin, fat, and (sometimes) muscle are used. This tissue is used to replace breast tissue and feels like a breast, but it never turns into real breast tissue. Since it isn't real breast tissue, the flap doesn't increase the risk of a new cancer forming.
While it is possible for breast cancer to recur after a mastectomy, breast reconstruction (either with an implant or flap) does not increase the risk of a new cancer forming, or the previous cancer returning.
I hope this info helps.
PRMA Plastic Surgery specializes in advanced breast reconstruction including DIEP flap, SIEA flap, GAP flap, TUG flap, Alloderm One-Step and fat grafting. We are In-Network for most US insurance plans and routinely welcome patients from across the USA. Please call (800) 692-5565 or email patientadvocate@PRMAplasticsurgery.com to learn more about your breast reconstruction options. Connect with other breast cancer patients at facebook.com/PRMAplasticsurgery.