Accelerated Partial-Breast Irradiation: Outcomes and Future Perspectives

Accelerated partial-breast irradiation (APBI) is an adjuvant radiotherapy technique that allows for the completion of radiation therapy (RT) in 1 week or less for women undergoing breast conservation. Traditionally delivered using interstitial brachytherapy, APBI can also be performed using newer techniques that include applicator-based brachytherapy and external-beam techniques (3D-conformal RT, intensity-modulated RT). Long-term outcomes with APBI encompass data from randomized trials, prospective data, and single-institution series, which have highlighted the efficacy as well as comparable recurrence risks compared with whole-breast irradiation (WBI). Prospective randomized comparisons of APBI with WBI have demonstrated similar rates of tumor control, although toxicity results vary based on the technique used with the potential for improved toxicity with brachytherapy based techniques. Moving forward, studies are under way to evaluate shorter courses of APBI, with evidence-based guidelines evolving to the increasing literature supporting the technique.