Standard or Hypofractionated Radiotherapy Versus Accelerated Partial Breast Irradiation (APBI)for Breast Cancer (SHARE)

• rate of local recurrence [ Time Frame: 5 years ] [ Designated as safety issue: No ]
  To estimate and compare the rate of local recurrence between the experimental and control arms.
  
  

• Ipsilateral breast recurrence-free survival [ Time Frame: 10 years ] [ Designated as safety issue: No ]
  To evaluate Ipsilateral breast recurrence-free survival
  
  
• Nodal regional recurrence-free survival [ Time Frame: 10 years ] [ Designated as safety issue: No ]
  To evaluate nodal regional recurrence-free survival
  
  
• Distant recurrence-free survival [ Time Frame: 10 years ] [ Designated as safety issue: No ]
  To evaluate distant recurrence-free survival
  
  
• Disease-specific survival [ Time Frame: 10 years ] [ Designated as safety issue: No ]
  To evaluate disease-specific survival
  
  
• Overall survival [ Time Frame: 10 years ] [ Designated as safety issue: No ]
  To evaluate the overall survival
  
  
• Toxicities: Measurement of the rate and type of toxicity (acute and late toxic effects) [ Time Frame: 10 years ] [ Designated as safety issue: No ]
  To evaluate rates and type of acute and late toxicities
  
  
• Cosmetic: comparison of the cosmetic result (according to both the physician and the patient) [ Time Frame: 10 years ] [ Designated as safety issue: No ]
  To evaluate Cosmetic results (Patient and Physician evaluations)
  
  
• Quality of Life and Satisfaction [ Time Frame: 10 years ] [ Designated as safety issue: No ]
  To evaluate the patient quality of life and patient satisfaction
  
  
• Medico-economic study [ Time Frame: 3 years ] [ Designated as safety issue: No ]
  To evaluate the cost of APBI compared with Standard and Hypofractionated irradiation
  
  

Following breast conservative surgery, patients will be stratified according to the following prognostic factors using a minimisation technique: age (<70 vs ≥70), HER2 status (HER2+ vs HER2-), hormonal receptor status (RH+ vs RH-) and lymph node invasion (pN0 vs pN0i+).

Patients will be allocated to receive either standard treatment, hypofractionated treatment or APBI.

Radiation therapy should be started between 4 and 12 weeks after the last surgery.

Patients treated with standard whole breast irradiation will receive a total dose of 50 Gy in 25 fractions, 2 Gy per day, 5 days a week. The boost of 16 Gy will be delivered in 8 fractions for all patients after completion of the 50 Gy, without interruption. All patients will receive one fraction per day, 5 fractions a week.

Patients treated with hypofractionated irradiation will receive a total dose of either 40 Gy (in 15 fractions, 2.66 Gy per day) or 42.5 Gy (in 16 fractions, 2.65 Gy per day)5 days a week.

Patients treated with APBI will receive a total dose of 40 Gy in 10 fractions, delivered twice a day over a time period of 5-7 days. Each daily dose must be separated by 6 hours.

Patients will be followed at 3 and 6 month after the last dose of irradiation, at 12 months after the date of last surgery and then on a yearly basis during 10 years.