Inclusion :  More than 18 years old Written informed consent Primary breast cancer in situ or invasive without evidence of systemic disease - non Stage IV or locally advanced non-operable breast cancer. ECOG performance status 0 or 1 Uni or Bilateral surgery even if prophylactic in one side Capacity to use a web-based app autonomously or with home-based support  Exclusion:  Mastectomy without reconstruction Pregnancy or lactation Previous radiation to breast/chest (e.g., lymphoma) Previous ipsilateral breast surgery due to malignant disease. Other neoplasm in the last 5 years (excluding basal cell carcinoma of the skin and adequately treated carcinoma in situ of the cervix) Severe skin disease that will contra-indicate the use of radiotherapy Prophylactic surgery