A systematic review and meta-analysis of intraoperative electron radiation therapy delivered with a dedicated mobile linac for partial breast irradiation in early breast cancer

• PBI is valid alternative to WBI in patients at low-risk of local relapse. • PBI is delivered by means of various techniques, one of which is IOeRT. • After IOeRT, an unexpectedly high LR rate was observed in the only phase III RCT. • Patient selection impacts on LR rates after IOeRT. • With appropriate patient selection IOeRT outcomes overlap with other RT techniques.