A meta-analysis of trials of partial breast irradiation Review


Authors: Goldberg, M.; Bridhikitti, J.; Khan, A. J.; McGale, P.; Whelan, T. J.
Review Title: A meta-analysis of trials of partial breast irradiation
Abstract: Purpose: Partial breast irradiation (PBI) is the delivery of radiation therapy (RT) limited to the tumor bed after breast conserving surgery. The results of recent trials of PBI compared with whole breast irradiation (WBI) have suggested conflicting results with respect to local control and toxicity. The purpose of this meta-analysis was to assess effectiveness of PBI and to compare the different techniques. Methods and Materials: A meta-analysis of aggregate data from published randomized trials was performed to examine the effectiveness of PBI compared with WBI in patients with invasive breast cancer and ductal carcinoma in situ. Relevant data were extracted. The primary outcome was any ipsilateral breast event (invasive or noninvasive). Secondary outcomes included acute and late toxicity. The results of randomized trials were pooled using a fixed effects model and the inverse variance method. Results: Fifteen trials involving 16,474 patients were identified. The majority of enrolled patients were >60 years of age and had T1N0 grade 1 to 2 disease treated with hormone therapy. The percent of ipsilateral breast events was higher in patients treated with PBI compared with WBI (5.0% vs 2.8%; risk ratio [RR], 1.72; 95% confidence interval [CI], 1.47-2.02). Heterogeneity (P =.0002) was observed between the 4 PBI techniques: external beam RT without computed tomography (CT) planning (RR, 2.06; 95% CI, 1.36-3.12); brachytherapy (RR, 1.21; 95% CI, 0.65-2.25); intraoperative RT (RR, 2.79; 95% CI, 2.08-3.73); and external beam RT with CT planning (RR, 1.25; 95% CI, 0.99-1.58). When external beam RT without CT planning and intraoperative RT trials were excluded, the percent of ipsilateral breast events was 3.3% versus 2.6%, respectively (RR, 1.25; 95% CI, 1.00-1.55; P =.05), and no heterogeneity was observed (P =.92). Overall, acute toxicity was less with PBI, and the effect on late toxicity varied by technique. Conclusions: Overall, WBI was more effective than PBI, but the effectiveness of PBI was technique related. PBI was less effective when given by external beam RT without CT planning or intraoperative therapy. Although PBI given by multicatheter brachytherapy or external beam RT with CT planning tended to be statistically less effective than WBI, the absolute difference between groups for ipsilateral breast events was very small (<1%), supporting these approaches for women considering PBI. © 2022 Elsevier Inc.
Keywords: adult; controlled study; aged; middle aged; cancer recurrence; cancer radiotherapy; cancer staging; outcome assessment; follow up; cancer grading; computer assisted tomography; breast; radiotherapy; tomography, x-ray computed; patient monitoring; pathology; breast neoplasms; radiation response; confidence interval; computerized tomography; breast tumor; partial mastectomy; irradiation; brachytherapy; intermethod comparison; hormonal therapy; external beam radiotherapy; toxicity; disease control; acute toxicity; randomized trial; meta analysis; mastectomy, segmental; intraoperative radiotherapy; meta-analysis; randomized controlled trial (topic); adverse event; accelerated partial breast irradiation; comparative effectiveness; external beam radiation therapy; clinical outcome; intraoperative radiation therapies; partial breast irradiation; procedures; inverse problems; whole-breast irradiation; invasive breast cancer; humans; human; female; article; late toxicities; x-ray computed tomography; breast radiotherapy; ductal breast carcinoma in situ
Journal Title: International Journal of Radiation Oncology, Biology, Physics
Volume: 115
Issue: 1
ISSN: 0360-3016
Publisher: Elsevier Inc.  
Date Published: 2023-01-01
Start Page: 60
End Page: 72
Language: English
DOI: 10.1016/j.ijrobp.2022.09.062
PUBMED: 36155214
PROVIDER: scopus
DOI/URL:
Notes: Article -- Export Date: 3 January 2023 -- Source: Scopus
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  1. Atif Jalees Khan
    153 Khan