Unacceptable Cosmesis in a Protocol Investigating Intensity-Modulated Radiotherapy With Active Breathing Control for Accelerated Partial-Breast Irradiation

The hypofractionated schedule and parameters commonly used for external beam APBI and prescribed by the ongoing national trial may be suboptimal, at least when highly conformal techniques such as IMRT with management of breathing motion are used. The V50 and V100 of the breast reference volume seem correlated with cosmetic outcome, and stricter limits may be appropriate in this setting.