Breast cancer remains the most common tumor in women, and new techniques for post- surgical breast reconstruction have been recently introduced. These new procedures include autologous fat grafting with or without the enrichment with autologous stromal vascular fraction (SVF), platelet-derived growth factors and insulin. The reported improvement of fat graft viability with these techniques likely depends on the presence in the SVF of multipotent resident adipose derived-stem cells (ASCs). The clinical advantage derives from the plasticity of ASCs and their ability to generate new functional adipose tissue and vessels. However, there is an ongoing debate regarding the possible interplay between breast tumor cells and resident or transplanted ASCs for their capacity to locally secrete growth factors. Most of the data in the literature concerning ASCs is derived from in vitro models, whereas the knowledge of ASC behavior in vivo remains scarce. Recent reports concerning SVF/ASC enrichment of fat graft did not describe any significant worsening of prognosis for patients undergoing those procedures. However, further studies and longer follow-ups are needed to specifically define technical procedures and to confirm the safety of procedures of SVF/ASC enrichment during post-surgical breast reconstruction.