Breast Cancer With Low Risk Of Local Recurrence: Partial and Accelerated Radiation With Three-Dimensional Conformal Radiotherapy (3DCRT) Vs. Standard Radiotherapy After Conserving Surgery (Phase III Study

This study was designed and developed in the Emilia Romania research and innovation program (PRI ER). The study does not have commercial sponsors and comes under the independent studies provided for by Ministerial Decree 17.12.2005. The PRI ER program will guarantee a contribution to the study for the first three years of recruitment through the regional Innovation Fund, to cover the costs of coordination and data management sustained by the Coordinating Center. Primary Objectives The study proposes to evaluate whether partial hypofractionated and accelerated irradiation of the sole surgical cavity, in patients suffering from breast cancer with low risk of local recurrence and who undergo conservative surgery, is not inferior to postoperative irradiation with conventional fractionation of the entire breast as regards local control (incidence of ipsilateral recurrences as prime event). Secondary Objectives Comparison of the global survivals, freedom from locoregional recurrences (with exception for contralateral tumors and second tumors), distant relapse-free (except for local or regional relapses or in the contralateral breast) in patients treated with conventional radiotherapy and accelerated partial radiation. To evaluate whether accelerated partial irradiation offers cosmetic results, acute toxicity comparable with conventional irradiation. Possible connection with other national and international studies Similar studies which nonetheless evaluate different methods of partial irradiation are currently underway. Study Design Multicenter phase III controlled randomized, unblinded study of non-inferiority. Number of cases Recruitment of 3302 patients is planned. Target Population of the Study Women aged = \> 49, ECOG 0-2, undergoing conservative breast surgery for invasive breast cancer, pT 1-2 (\< 3 cm in diameter) pN0-N1 M0, unifocal, resection margins histologically negative (³ 2 mm) at first intervention or after subsequent widening. Duration of the recru