Table 1.

Select randomized controlled trials of accelerated partial breast irradiation (APBI) after breast conserving surgery (BCS)

	GEC-ESTRO	ELIOT	TARGIT-A	IMPORT LOW	OCOG-RAPID	NSABP-B39/RTOG 0413	University of Florence
Number of patients randomized	n = 1184	n = 1305	n = 3451	n = 2018	n = 2135	n = 4216	n = 520
Primary endpoint/trial design	Local recurrence/non-inferiority trial	IBTR/non-inferiority trial	IBTR/non-inferiority trial	IBTR/non-inferiority trial	IBTR/non-inferiority trial	IBTR/equivalence trial	IBTR/equivalence trial
Median follow-up	6.6 years	5.8 years	2.4 years	6 years	8.6 years	10.2 years	10 years
Study eligibility/exclusion criteria	≥ 40 years Negative surgical margins (≥ 2 mm for IDC, ≥ 5 mm for ILC) ≤ 3 cm, pN0/pN1mi Unifocal Pure DCIS allowed if Van Nuys Prognostic index score < 8 Grade I-III LVI & EIC excluded Paget’s or skin involvement excluded	48–75 years All histologies and grades eligible Suitable for BCS ≤ 2.5 cm	≥ 45 years IDC Suitable for BCS Unifocal on conventional imaging	≥ 50 years IDC (ILC excluded) Negative surgical margins (≥ 2 mm) ≤ 3 cm, pN0–1 grade I-III LVI allowed Unifocal	≥ 40 years IDC (ILC excluded) Negative surgical margins ≤ 3 cm (invasive and in situ combined), pN0-N1mi or N0i+ Pure DCIS allowed Grade I-III LVI allowed Multicentric excluded	> 18 years All histologies and grades eligible Negative surgical margins ≤ 3 cm, pN0–1 DCIS allowed Unifocal/multifocal only (multicentric excluded)	> 40 years IDC/lobular carcinoma Negative surgical margins (≥ 5 mm) ≤ 2.5 cm, pN0-N1 Pure DCIS Grade I-III LVI allowed Unifocal only EIC excluded

IBTR ipsilateral breast tumor recurrence, EIC extensive intraductal component, LVI lymphovascular invasion, DCIS ductal carcinoma in situ, LCIS lobular carcinoma in situ, mi micrometastases, i+ isolated tumor cells, IDC invasive ductal carcinoma, ILC invasive lobular carcinoma, BCS breast conserving surgery