Hypofractionated radiation therapy in the treatment of early-stage breast cancer.

Hypofractionated radiation refers to the use of fewer, larger-dose radiation treatments that are usually given over a shorter time period compared to conventional radiation fraction sizes. Randomized trials of hypofractionated whole breast irradiation (WBI) have demonstrated comparable outcomes as conventional fractionation. For a higher-risk population for local recurrence, a phase 3 trial by the Radiation Therapy Oncology Group (RTOG) is currently studying hypofractionated WBI with a concurrent tumor bed boost over 3 weeks. Accelerated partial breast irradiation limits radiation to the region of the tumor bed for 1-3 weeks and is the subject of an ongoing randomized trial by the National Surgical Breast and Bowel Project and RTOG. Questions remain for hypofractionation about optimal patient selection, radiation techniques, and the risk of late toxicity. But results from current trials could make hypofractionation more widely accepted for patients with early-stage breast cancer.