In order to reduce mutilation, nipple-areola complex (NAC) conservation can be proposed for the treatment of breast cancer when mastectomy is indicated. To reduce the risk of retro areolar recurrence, a novel radiosurgical treatment combining subcutaneous mastectomy with intraoperative radiotherapy (ELIOT) is proposed. One thousand and one nipple sparing mastectomies (NSM) were performed from March 2002 to November 2007 at the European institute of oncology (EIO), for invasive carcinoma in 82% of the patients and in situ carcinoma in 18%.Clinical complications, aesthetic results, oncological and psychological results were recorded. A comparison was performed between the 800 patients who received ELIOT and the 201 who underwent delayed one-shot radiotherapy on the days following the operation. The median follow up time was 20 months (range 1-69) for a follow up performed in 83% of the patients. The NAC necrosed totally in 35 cases (3.5%) and partially in 55 (5.5%) and was removed in 50 (5%). Twenty infections (2%) were observed and 43 (4.3%) prostheses removed. The median rate of the patients for global cosmetic result on a scale ranging from 0 (worst) to 10 (excellent) was 8. Evaluation by the surgeon in charge of the follow-up gave a similar result. Only 15% of the patients reported a partial sensitivity of the NAC. Of the fourteen (1.4%) local recurrences, ten occurred close to the tumour site, all far from the NAC corresponding to the field of radiation. No recurrences were observed in the NAC. In a group of patients characterized by a very close free margin under the areola, no local recurrence was observed. Overall, 36 cases of metastases and 4 deaths were observed. No significant outcome difference was observed between the 800 patients receiving intraoperative radiotherapy (ELIOT) and the 201 patients receiving delayed irradiation.