Eur. J. Cancer 2015-03-01
Accelerated partial breast irradiation using intensity-modulated radiotherapy versus whole breast irradiation: 5-year survival analysis of a phase 3 randomised controlled trial.
ABSTRACT
BACKGROUND
Accelerated partial breast irradiation (APBI) has been introduced as an alternative treatment method for selected patients with early stage breast cancer (BC). Intensity-modulated radiotherapy (IMRT) has the theoretical advantage of a further increase in dose conformity compared with three-dimensional techniques, with more normal tissue sparing. The aim of this randomised trial is to compare the local recurrence and survival of APBI using the IMRT technique after breast-conserving surgery to conventional whole-breast irradiation (WBI) in early stage BC.
METHODS
This study was performed at the University of Florence (Florence, Italy). Women aged more than 40years affected by early BC, with a maximum pathological tumour size of 25mm, were randomly assigned in a 1:1 ratio to receive either WBI or APBI using IMRT. Patients in the APBI arm received a total dose of 30 Gy to the tumour bed in five daily fractions. The WBI arm received 50Gy in 25 fractions, followed by a boost on the tumour bed of 10Gy in five fractions. The primary end-point was occurrence of ipsilateral breast tumour recurrences (IBTRs); the main analysis was by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT02104895.
FINDINGS
A total of 520 patients were randomised (260 to external WBI and 260 to APBI with IMRT) between March 2005 and June 2013. At a median follow-up of 5.0 years (Interquartile Range (IQR) 3.4-7.0), the IBTR rate was 1.5% (three cases) in the APBI group (95% confidence interval (CI) 0.1-3.0) and in the WBI group (three cases; 95% CI 0.0-2.8). No significant difference emerged between the two groups (log rank test p=0.86). We identified seven deaths in the WBI group and only one in the APBI group (p=0.057). The 5-year overall survival was 96.6% for the WBI group and 99.4% for the APBI group. The APBI group presented significantly better results considering acute (p=0.0001), late (p=0.004), and cosmetic outcome (p=0.045).
INTERPRETATION
To our knowledge, this is the first randomised study using the IMRT technique for APBI delivery. No significant difference in terms of IBTR and overall survival was observed between the two arms. APBI displayed a significantly better toxicity profile.
Related Questions
Since we know that both the "Canadian" fractionation and partial breast irradiation work as treatment for early stage breast cancer in the same patien...
New answer by Radiation Oncologist at Rush University Medical Center (March 29, 2016)
Another study presented at ASTRO was using START or Canadian fractionation to partial breast (September 2004 Volume 60, Issue 1, Supplement, Pages S273&nd...
Are there any situations where a patient is a suitable candidate for ABPI but you still encourage standard whole breast hypofractionation?
New comment by Radiation Oncologist at Lake Huron Medical Center ( October 26, 2017)
Absolutely agree. All are different and have different roles. The question had been worded oddly initially, comparing a technique (EBRT) to a volume (partial breast) .
Particularly for patients too large for prone breast treatment, do you use a breast immobilization device or bra? Do you change your fractionat...
New comment by Radiation Oncologist at Thomas Jefferson University ( August 31, 2018)
We have used a 60 cc syringe under the breast with much less inframammary fold breakdown.
Do you consider this regimen based on the 10 year results of the UK FAST trial?
New comment by Radiation Oncologist at Cleveland Clinic ( March 30, 2020)
Agreed, 10 year data from Livi was presented at SABCC (https://www.abstractsonline.com/pp8/#!/7946/presentation/1921). Additionally, I have shifted to 5 days in a row (ACCEL t...
https://www.abstracts2view.com/sabcs18/view.php?nu=SABCS18L_568
Any concerns regarding toxicity with APBI?
New comment by Radiation Oncologist at Cleveland Clinic ( January 23, 2019)
I cant speak to how many were on B-39 for these groups. Overall, I think there is limited data under 40 so I do not routinely offer APBI to patients in this group. Similarly b...
What techniques are most effective to minimize contralateral breast, heart, and lung dose? Do you recommend conventional fractionation?
New comment by Radiation Oncologist at UP Health System, Marquettte ( July 11, 2019)
I have obtained the best plan using Tomotherapy
New comment by Radiation Oncologist at Bismarck Cancer Center ( August 29, 2020)
Yeah, in my own practice, if we can't identify the cavity with confidence (whether due to oncoplastic technique or even sometimes following adjuv chemo or other delays during ...
New comment by Radiation Oncologist at OSF Saint Anthony's Health Center-Alton ( January 25, 2021)
You are correct, back in the 2D era, you would shoot for 2 cm of lung or less on the tangential field simulation films.
As opposed to the every other day Florence regimen.
Would you use mini tangents, 3D conformal, IMRT?
New comment by Radiation Oncologist at Cleveland Clinic ( April 24, 2021)
We typically use VMAT with 2-3 partial arcs. Chest wall dose depends on location of cavity but still, dose is lower than when using tangents for whole breast that cover entire...
Do you boost when employing this regimen?
New answer by Radiation Oncologist at University of Colorado School of Medicine (November 28, 2021)
This metric is antiquated and based upon the OCOG (Whelan et al., PMID 20147717) trial comparing 50 Gy to 42 Gy for whole breast RT. For this trial performed in the mid-...