McGill University Health Centre, Montreal, QC, Canada.
Citations 3
Concurrent Versus Sequential Radiation Dose Escalation to the Surgical Cavity for Conservative Treatment of High-Risk Early Breast Cancer: NRG/RTOG 1005 Phase III Trial
PURPOSE For patients with breast cancer undergoing breast conservation, escalating the dose (boost) of radiation to the lumpectomy cavity after whole-breast irradiation (WBI) reduces ipsilateral breast recurrence (IBR) but extends treatment duration. This phase III trial investigated whether boost delivery during WBI versus after WBI provides noninferior IBR and preserves cosmetic appearance. METHODS NRG/RTOG 1005 randomly assigned patients at higher risk for IBR after lumpectomy and axillary surgery to either a sequential boost of 12 Gy in six fractions(F) or 14 Gy in 7F after WBI of 50 Gy in 25F or 42.7 Gy in 16F (sequential arm) or a concurrent boost of 8 Gy in 15F of 0.53 Gy per day with WBI of 40 Gy in 15F (concurrent arm) using 3-dimensional conformal radiation therapy (RT) or intensity-modulated RT. Based on 1.59% 5-year IBR for the sequential arm, defining the noninferiority margin as a hazard ratio upper limit on the 90% CI of 2.12, 2,312 patients provide 80% power for noninferiority of IBR as first recurrence for the concurrent arm. Secondary end points included disease-free survival and overall survival, adverse events (AEs), and cosmetic outcomes. RESULTS Between May 24, 2011, and June 20, 2014, 2,354 patients were randomly assigned, with 2,255 eligible for analysis (sequential arm, n = 1,118; concurrent arm, n = 1,137). With median follow-up of 7.3 years, there were 56 IBR events; 5- and 7-year IBR were 2.1% and 2.2% on the sequential arm and 1.9% and 2.6% on the concurrent arm, respectively. The noninferiority criterion was met: HR (90% CI): 1.31 (0.84 to 2.04), P = .037. No differences were observed in AEs, cosmetic outcomes, or survival between arms. CONCLUSION Concurrent boost during WBI results in noninferior IBR compared with sequential boost without worsening toxicity or cosmetic outcomes and reduces overall treatment time.
Randomised controlled trials on radiation dose fractionation in breast cancer: systematic review and meta-analysis with emphasis on side effects and cosmesis
Abstract Objective To provide a comprehensive assessment of various fractionation schemes in radiation therapy for breast cancer, with a focus on side effects, cosmesis, quality of life, risks of recurrence, and survival outcomes. Design Systematic review and meta-analysis. Data sources Ovid MEDLINE, Embase, and Cochrane Central Register of Controlled Trials (from inception to 23 October 2023). Study selection Included studies were randomised controlled trials focusing on conventional fractionation (CF; daily fractions of 1.8-2 Gy, reaching a total dose of 50-50.4 Gy over 5-6 weeks), moderate hypofractionation (MHF; fraction sizes of 2.65-3.3 Gy for 13-16 fractions over 3-5 weeks), and/or ultra-hypofractionation (UHF; schedule of only 5 fractions). Data extraction Two independent investigators screened studies and extracted data. Risk of bias and quality of evidence were assessed using the Cochrane Collaboration’s tool and the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) approach, respectively. Data synthesis Pooled risk ratios (RRs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using a random effects model. Heterogeneity was analysed using Cochran’s Q test and I 2 statistic. Network meta-analysis was used to integrate all available evidence. Main outcome measures The pre-specified primary outcome was grade ≥2 acute radiation dermatitis and late radiation therapy related side effects; secondary outcomes included cosmesis, quality of life, recurrence, and survival metrics. Results From 1754 studies, 59 articles representing 35 trials (20 237 patients) were assessed; 21.6% of outcomes showed low risk of bias, whereas 78.4% had some concerns or high risk, particularly in outcome measurement (47.4%). The RR for grade ≥2 acute radiation dermatitis for MHF compared with CF was 0.54 (95% CI 0.49 to 0.61; P<0.001) and 0.68 (0.49 to 0.93; P=0.02) following breast conserving therapy and mastectomy, respectively. Hyperpigmentation and grade ≥2 breast shrinkage were less frequent after MHF than after CF, with RRs of 0.77 (0.62 to 0.95; P=0.02) and 0.92 (0.85 to 0.99; P=0.03), respectively, in the combined breast conserving therapy and mastectomy population. However, in the breast conserving therapy only trials, these differences in hyperpigmentation (RR 0.79, 0.60 to 1.03; P=0.08) and breast shrinkage (0.94, 0.83 to 1.07; P=0.35) were not statistically significant. The RR for grade ≥2 acute radiation dermatitis for UHF compared with MHF was 0.85 (0.47 to 1.55; P=0.60) for breast conserving therapy and mastectomy patients combined. MHF was associated with improved cosmesis and quality of life compared with CF, whereas data on UHF were less conclusive. Survival and recurrence outcomes were similar between UHF, MHF, and CF. Conclusions MHF shows improved safety profile, cosmesis, and quality of life compared with CF while maintaining equivalent oncological outcomes. Fewer randomised controlled trials have compared UHF with other fractionation schedules, but its safety and oncological effectiveness seem to be similar with short term follow-up. Given the advantages of reduced treatment time, enhanced convenience for patients, and potential cost effectiveness, MHF and UHF should be considered as preferred options over CF in appropriate clinical settings, with further research needed to solidify these findings. Systematic review registration PROSPERO CRD42023460249.
Looking Back: International Practice Patterns in Breast Radiation Oncology From a Case-Based Survey Across 54 Countries During the First Surge of the COVID-19 Pandemic
PURPOSE The COVID-19 pandemic has profoundly affected cancer care worldwide, including radiation therapy (RT) for breast cancer (BC), because of risk-based resource allocation. We report the evolution of international breast RT practices during the beginning of the pandemic, focusing on differences in treatment recommendations between countries. MATERIALS AND METHODS Between July and November 2020, a 58-question survey was distributed to radiation oncologists (ROs) through international professional societies. Changes in RT decision making during the first surge of the pandemic were evaluated across six hypothetical scenarios, including the management of ductal carcinoma in situ (DCIS), early-stage, locally advanced, and metastatic BC. The significance of changes in responses before and during the pandemic was examined using chi-square and McNemar-Bowker tests. RESULTS One thousand one hundred three ROs from 54 countries completed the survey. Incomplete responses (254) were excluded from the analysis. Most respondents were from the United States (285), Japan (117), Italy (63), Canada (58), and Brazil (56). Twenty-one percent (230) of respondents reported treating at least one patient with BC who was COVID-19–positive. Approximately 60% of respondents reported no change in treatment recommendation during the pandemic, except for patients with metastatic disease, for which 57.7% (636/1,103; P < .0005) changed their palliative practice. Among respondents who noted a change in their recommendation during the first surge of the pandemic, omitting, delaying, and adopting short-course RT were the most frequent changes, with most transitioning to moderate hypofractionation for DCIS and early-stage BC. CONCLUSION Early in the COVID-19 pandemic, significant changes in global RT practice patterns for BC were introduced. The impact of published results from the FAST FORWARD trial supporting ultrahypofractionation likely confounded the interpretation of the pandemic's independent influence on RT delivery.