Adjuvant Radiation Therapy for Breast Cancer

Abstract

The objective of adjuvant radiation therapy (RT) is to eradicate any tumor deposits following surgery for patients treated by either breast conserving surgery or mastectomy. Radiotherapy reduces the risk of local relapse and reduces breast cancer mortality. There have been significant advances in radiotherapy technology, with sophisticated imaging integrated into planning systems using techniques that protect the heart with shielding or deep inspiration breath holding (DIBH). Modern intensity modulated radiotherapy (IMRT) or volumetric modulatedarc therapy (VMAT) techniques can be used to shape the dose distributions around the heart in order to reduce the high-dose volume. Nevertheless, this is usually at the cost of a low-dose spill to the lungs, the contralateral breast and the whole heart. Breast-conserving therapy (BCT) for early-stage breast cancer has a survival rate comparable to mastectomy, therefore BCS and radiation have become the standard treatment for stage I–II breast cancer. After BCS, radiation therapy in the form of Whole Breast Radiation Therapy (WBRT) is the standard adjuvant treatment, with 90–95 percent local control rates. After breast conserving surgery, radiation can reduce the chance of recurrence.