Innovative Approaches to Accelerated Partial Breast Irradiation

Early outcomes from studies evaluating accelerated partial breast irradiation (APBI) as an alternative adjuvant treatment after breast-conserving surgery for early-stage breast cancer have been promising. The method with the longest-standing history and supporting outcome data for APBI is multi-catheter interstitial brachytherapy. The advent of a single-channel intracavitary device, Mammosite balloon, has allowed a more simple and reproducible approach and in turn has led to an increased number of patients treated with APBI. More recently, several investigators have explored emulating the brachytherapy methods with a noninvasive external beam approach. Currently, a large phase III clinical trial is evaluating these three APBI approaches with the conventional fractionated whole breast radiation course. Based on the favorable outcomes of the above techniques, there have been several innovative methods of APBI that have been developed in an effort to bridge the benefits and overcome certain limitations inherent in existing techniques. These novel approaches will be reviewed, and a summary of the advantages, disadvantages, and phase of clinical development will be provided.