Table 2.

Clinical, pathologic, and treatment-related characteristics of the EBRT and boost-IORT groups.

	EBRT			Electron boost		X-ray -boost		Total
	N		%	N	%	N	%	N	%
	657		100	706	100	283	100	1646	100
Stage
1	89		13.50	132	19	30	10.60	251	24.70
2	428		65.10	430	61.80	168	59.40	1026	57.40
3	140		21.30	134	19.30	85	30	359	17.90
Total	657		100	696	100	283	100	1636	100
Size
≤2.5 cm	312		53.10	374	58.30	115	42.40	801	60.00
2.5 = 3 cm	144		24.50	99	15.40	39	14.40	282	17.00
>3 cm	132		22.40	169	26.30	117	43.20	418	23.10
Total	588		100	642	100	271	100	1501	100
Grade
1	54		8.60	47	7.00	31	12.30	132	10.30
2	336		53.40	379	56.80	97	38.30	812	53.50
3	239		38	241	36.10	125	49.40	605	36.20
Total	629		100	667	100	253	100	1549	100
LVI
Positive	254		42	328	49.90	118	72.40	700	43.00
Negative	351		58	329	50.10	45	27.60	725	57.00
Total	605		100	657	100	163	100	1425	100
Ki67
>30%	32		11.80	176	29.00	23	35.90	231	27.10
≤30%	239		88.20	431	71.00	41	64.10	711	72.90
Total	271		100	607	100	64	100	942	100
ER
Positive	372		76.40	517	72.30	175	72.30	1064	77.30
Negative	115		23.60	158	27.70	67	27.70	340	22.70
Total	487		100	675	100	242	100	1404	100
HER2
Positive	91		23.80	89	14.00	68	25.50	248	19.10
Negative	292		76.20	547	86.00	199	74.50	1038	80.90
Total	383		100	636	100	267	100	1286	100
Age
<40	160		24.90	135	20.90	88	31.10	383	19.80
=40–50	193		30.00	236	36.50	100	35.30	529	31.90
≥50	290		45.10	275	42.60	95	33.60	660	48.30
Total	643		100	646	100	283	100	1572	100
Histology
IDC	591		90.90	449	64.50	161	62.60	1201	74.90
ILC	25		3.80	83	11.90	35	13.60	143	8.90
IDC + DCIS	23		3.50	93	13.40	39	15.20	155	9.70
IDC + ILC	2		0.30	60	8.60	19	7.40	81	5.10
Others	9		1.40	11	1.60	3	1.20	23	1.40
Adjuvant therapy
CT + HT	245		68.40	435	72.00	166	70.00	846	70.60
HT alone	33		9.20	19	3.10	6	2.50	58	4.80
CT alone	80		22.30	150	24.80	65	27.40	295	24.60
Total	358		100	604	100	237	100	1199	100