This is a response-adaptive (RAR) prospective randomized study with a long-term follow-up and the aim of this clinical study is to measure with qualitative and quantitative indicators the changes in cosmetic results, quality of life and patient satisfaction after delayed- immediate breast reconstruction with standardized technique Skin Reducing Nipple sparing mastectomy, SRNSM and SSM with standardized horizontal skin incision. According to our hypothesis, SRNSM with standardized technique on pendulous/ ptotic breasts is a safe procedure compared to SSM. It also promotes the cosmetic efficacy of SRNSM with the removal of the entire glandular tissue through avoidance of the reduction of projection, the need later nipple reconstruction surgery and of areola tattoo. In our study we propose that compared to one of the well-known and widely investigated studied SSM, our current standardized SRNSM technique is able to perform similar oncologically safe entire gland tissue removal, with low complication rate, accommodating for adjuvant treatments. Furthermore, it may provide superior cosmetic results than SSM (NAC is not removed, projection is maintained, and there is no need for further nipple reconstruction or tattoo) with high patient satisfaction which is maintained long term.