[3rd Hungarian Breast Cancer Consensus Conference - Radiotherapy Guidelines].

The radiotherapy expert panel revised and updated the radiotherapy (RT) guidelines accepted in 2009 at the 2nd Hungarian Breast Cancer Consensus Conference based on new scientific evidence. Radiotherapy of the conserved breast is indicated in ductal carcinoma in situ (St. 0), as RT decreases the risk of local recurrence by 60%. In early stage (St. I-II) invasive breast cancer RT remains a standard treatment following breast conserving surgery. However, in elderly (≥70 years) patients with stage I, hormone receptor positive tumour hormonal therapy without RT can be considered. Hypofractionated (15×2.67 Gy) whole breast irradiation and for selected cases accelerated partial breast irradiation are validated treatment alternatives of conventional (25×2 Gy) whole breast irradiation. Following mastectomy RT significantly decreases the risk of locoregional recurrence and improves overall survival of patients having 1 to 3 (pN1a) or ≥4 (pN2a, pN3a) positive axillary lymph nodes. In selected cases of patients with 1 to 2 positive sentinel lymph nodes axillary dissection can be omitted and substituted with axillary RT. After neoadjuvant chemotherapy (NAC) followed by breast conserving surgery whole breast irradiation is mandatory, while after NAC followed by mastectomy locoregional RT should be given in cases of initial stage III-IV and ypN1 axillary status.