During the early decades of radiation therapy for breast cancer, local control of disease was documented consistently but, enigmatically, an anticipated impact on breast cancer survival was not observed, leading to confusion in our understanding of the natural history of breast cancer and radiation effects. Now, almost 90 years after its first use in breast cancer, technology developments in diagnostic imaging and radiation therapy have elucidated parts of this enigma. The data now available demonstrate a significant impact of radiation therapy on survival as well as disease control and treatment-related mortality, opening a doorway to understanding the powerful impact of radiation therapy on both breast cancer and critical organs. Efforts are focused on leveraging novel techniques to maximize the benefits of radiation for breast cancer patients.
Keywords: deep-inspiration breath hold; intensity-modulated radiation therapy, IMRT; proton therapy.