American Brachytherapy Society Task Group Report: Long-term control and toxicity with brachytherapy for localized breast cancer

PURPOSE There has been significant controversy regarding the equivalency of accelerated partial breast irradiation to whole-breast irradiation. With the recent publication of a large, randomized trial comparing these two treatment modalities, an update on the current state of knowledge of brachytherapy-based accelerated partial breast irradiation, with respect to local control and toxicities, would be useful to practitioners and patients. Methods and Materials A systematic literature review was conducted examining articles published between January 2000 and April 2016 on the topics “brachytherapy” and “breast.” A total of 67 articles met inclusion criteria, providing outcomes on local tumor control and/or toxicity for breast brachytherapy. RESULTS Reported 5-year local failure rates were 1.4–6.1% for multicatheter interstitial brachytherapy (MIB) and 0–5.7% for single-entry brachytherapy catheters when delivered to patients with standard selection criteria. Toxicity profiles are acceptable, with cosmetic outcomes comparable to whole-breast irradiation. The reported rates of infection were 0–12%. Symptomatic fat necrosis was found in 0–12% and 0–3.2% of patients treated with MIB and single-entry brachytherapy catheters, respectively. Late Grade ≥3 telangiectasias and fibrosis were reported in 0–8% and 0–9.1% of patients treated with MIB, respectively. These side effects were less common with single-entry brachytherapy catheters (0–2.0% and 0%, respectively). Conclusions Breast brachytherapy is a treatment technique that provides acceptable rates of local control in select patients, as demonstrated by Level I evidence. The side effect profile of this treatment is well documented and should be shared with patients when considering this treatment modality.