 In our study, we propose to treat these patients with a total dose of 16 Gy in one fraction. This dose is calculated taking into account a report alphabeta for the breast, on the order of 3.4 Gy for late toxicity and 4.6 Gy for local control 13. Applying the linear-quadratic model with alphabeta for the breast of 4, 16 Gy in one fraction is calculated as radio-biologically equivalent to 53 Gy in conventional fractionation 14,15. Biological Equivalence of this dose is between the dose in the protocols IPAS intraoperative electron or X-ray photons of 50 kV 21 Gy in one fraction, 87 Gy EQD2 alphabeta 4.6 5.8 and the post-operative irradiation of 34-38 Gy in 10 fractions, 5 days 42 Gy EQD2 alphabeta 4.6. 