Table 2.

American Society for Radiation Oncology and GEC-ESTRO recommendations on patient selection criteria for Accelerated Partial Breast Irradiation

	ASTRO	GEC-ESTRO	ASTRO	GEC-ESTRO	ASTRO	GEC-ESTRO
Factor	Suitable	Low-risk	Cautionary	Intermediate-risk	Unsuitable	High-risk
Patient factors
Age (yr)	≥ 60	> 50	50-59	40-50	< 50	< 40
BRCA1/2 mutation	Not present	Not defined	Not present	Not defined	Present	Not defined
Pathologic factors
Tumor size (cm)	≤ 2	≤ 3	2.1-3.0	≤ 3	> 3	> 3
T stage	T1	T1-2	T0 or T2	T1-2	T3-4	T2 (> 3 cm), T3-4
Histology	IDC or other favorable subtypes	IDC, mucinous, tubular, medullary and colloid carcinoma	ILC allowed	ILC allowed	Any	Any
Grade	Any	Any	Any	Any	Any	Any
Pure DCIS	Not allowed	Not allowed	≤ 3 cm	Allowed	> 3 cm	Any
EIC	Not allowed	Not allowed	≤ 3 cm	Not allowed	> 3 cm	Allowed
Associated LCIS	Allowed	Allowed	Allowed	Allowed	Allowed	Allowed
Multicentricity	Unicentric	Unicentric	Unicentric	Unicentric	Multicentric	Multicentric
Multifocality	Clinically unifocal ≤ 2 cm	Unifocal	Clinically unifocal 2.1-3 cm	Multifocal (limited within 2 cm of the index lesion)	Clinically multifocal, > 3 cm	Multifocal (> 2 cm from the index lesion)
LVSI	No	Not allowed	Limited/focal	Not allowed	Extensive	Allowed
ER status	Positive	Any	Negative	Any	Any	Any
Surgical margins	≥ 2 mm	≥ 2 mm	< 2 mm	< 2 mm	Positive	Positive
Nodal factors
N stage	pN0 (i-, i+)	pN0	pN0 (i-, i+)	pN1mi, pN1a	≥ pN1	pNx, ≥ pN2a
Nodal surgery	SN biopsy or ALND				None performed
Neoadjuvant therapy	Not allowed	Not allowed	Not allowed	Not allowed	If used	If used

DCIS: Ductal carcinoma in situ; EIC: Extensive intraductal component; LCIS: Lobular carcinoma in situ; ASTRO: American Society for Radiation Oncology.