Accelerated Partial Breast Irradiation With 3D-CRT and IMRT (APERT)

The purpose of this study is to determine in a phase II clinical trial whether accelerated partial breast irradiation after breast conserving surgery using 3 dimensional external beam radiotherapy (3D-CRT) and intensity modulated radiotherapy (IMRT) for low-risk invasive breast cancer patients is safe without causing serious late radiation side-effects.