 - The high-risk group not suitable for ASTRO 2.3. Therefore, it is possible to propose to a patient a randomized clinical tria IPAS, to subject it belongs to the group low risk. The results of phase II trials as a long-term analysis of the matched team of William Beaumont Hospital 4 and the phase III trial using intra-operative radiation photons in low energy X whose results were recently published 5 confirm the value of this new therapeutic concept for post-operative breast cancer at low risk of local recurrence. 