Phase III clinical trial - Sein Adjuvant

The standard treatment of localized breast cancers consists of surgical removal of the tumor at the breast or removal of the entire breast and lymph nodes (sentinel lymph node and / or axillary dissection) with or without chemotherapy followed by radiotherapy on the breast or thoracic wall and the lymph node areas from 5 to 6.5 weeks.;Shorter radiotherapy treatments over 3 weeks for breast cancer without lymph node involvement have been equally effective and have no more side effects in several clinical trials involving several thousand patients. This called hypofractioned radiotherapy has become a standard for breast cancers in the absence of lymph node involvement in postmenopausal women.;The objective of the HypoG01 trial is to evaluate hypofractioned radiotherapy in women who require radiotherapy in the breast or chest wall and lymph node areas by comparing standard over 5 to 6.5 weeks and hypofractionated irradiation over 3 weeks analyzing the possible side effects and in particular the risk of lymphedema (swelling of the arm on the side treated) and the effectiveness of these treatments.