Efficacy and safety of accelerated partial breast irradiation: a meta-analysis of published randomized studies

// Gengchun Liu 1, * , Zhongyi Dong 2, * , Baqun Huang 1 , Yuelong Liu 1 , Yan Tang 1 , Qing Li 1 and Yihui Zhu 1 1 Department of Radiation Oncology, Xiangtan City Central Hospital, Xiangtan 411100, Hunan Province, China 2 Department of Radiation Oncology, Nonfan Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China * These authors contributed equally to this work Correspondence to: Gengchun Liu, email: for-magi@outlook.com Keywords: efficacy, safety, accelerated partial breast irradiation, meta-analysis Received: March 16, 2017 Accepted: June 29, 2017 Published: July 13, 2017 ABSTRACT Background and purpose: Accelerated partial breast irradiation (APBI) technology has theoretical advantages in comparison with traditional adjuvant radiation therapy (whole-breast irradiation; WBI) after breast-conserving surgery. However, published randomized controlled trials have shown inconsistent outcomes. Therefore, a comprehensive assessment of the effectiveness and safety of APBI technology is needed. Results: A total of 7 studies of 7452 patients were included in this analysis. All 7 studies reported local recurrence as an outcome. Meta-analysis of 5 trials that included 6486 patients showed significantly different 5-year local recurrence rates for APBI and WBI groups (hazard ratio = 4.54, 95% confidence interval: 1.78–11.61, p = 0.002). Further analysis showed that this difference may be related to the choice of treatment methods. Benefit was conferred to the APBI group for the outcome of non-breast cancer deaths. There was no significant difference between the two groups in terms of nodal recurrence, systemic recurrence, overall survival, or mortality rates. Toxicity side effects and cosmetic effects were similar in both groups, but intraoperative radiotherapy seemed to have a greater acute response. Material and methods: Searches for relevant randomized controlled trials of APBI versus WBI were performed using the following sources: PubMed, EMBASE, Cochrane Library, Web of Science. Two independent observers evaluated the identified studies. The meta-analysis was conducted using RevMan 5.2 software. Conclusions: Although the analysis showed that patients receiving APBI had a higher local recurrence rate, subgroup analyses suggested that this might be related to treatment options. Patients who receive accurate radiotherapy may have greater benefits. APBI is a promising treatment technology and more phase III clinical trials are expected based on new treatments.