Is kV Intraoperative Radiation Therapy an Acceptable Method for Partial Breast Irradiation?

Multiple large prospectively randomized trials of postoperative partial breast irradiation (PBI) have established it as a viable alternative to whole-breast irradiation for risk-adapted breast conserving management of early stage disease. An area of controversy remains regarding the relative efficacy, safety, and utility of intraoperative radiation therapy as a PBI technique. This is particularly true regarding the use of a 50 kV x-ray device, whereby the inherent dosimetry of the applicator results in a low dose of radiation to an exceedingly small volume of tissue. A critical analysis of the current clinical data would strongly support the view that intraoperative radiation therapy with a 50 kV x-ray device is associated with inferior outcomes compared with the variety of currently available modalities used for postoperative PBI.