NCCN Guidelines Update: Evolving Radiation Therapy Recommendations for Breast Cancer.

In the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Breast Cancer, among adjuvant radiotherapy options for whole breast irradiation after breast-conserving surgery, hypofractionation is preferred. For the use of accelerated partial-breast irradiation, the NCCN Guidelines have adopted the updated definition of "suitability" used by the American Society for Radiation Oncology. Regional nodal irradiation is indicated either in the setting of breast-conserving surgery or after mastectomy-for women with >= 4 positive nodes and should be strongly considered for 1 to 3 positive lymph nodes and select patients with node-negative disease deemed at high risk for recurrence.