Table 1.

Baseline patient, tumor, and treatment characteristics

	CF-WBI (n=149)		HF-WBI (n=138)		P*
	N	%	N	%
Patient characteristics
Age at diagnosis (years)					0.55
40–49	13	9	19	14
50–59	55	37	46	33
60–69	59	40	51	37
70 and older	22	15	22	16
Race					0.68
White Non-Hispanic	116	78	99	72
Hispanic	16	11	20	15
Black Non-Hispanic	15	10	17	12
Asian Non-Hispanic	2	1	2	1
Menopausal Status					0.23
Premenopausal	9	6	13	9
Perimenopausal	8	5	3	2
Postmenopausal	132	89	122	88
Bra Cup Size					0.53
A	13	9	7	5
B	31	21	34	25
C	50	34	46	33
D	40	27	35	25
DD	12	8	16	12
DDD	2	1	0	0
EE	1	1	0	0
BMI Quartile (kg/cm2)					0.08
<24.48	35	24	37	27
24.48 – <29.18	38	26	35	25
29.18 – <33.64	30	20	40	29
>33.64	46	31	26	19
Physician-Assessed Cosmesis					0.16
Excellent-Good	135	91	131	95
Fair-Poor	14	10	7	5
Tumor characteristics
Tumor Behavior					0.07
Invasive	110	74	114	83
DCIS	39	26	24	17
Tumor Grade					0.46
1	40	27	34	25
2	70	47	73	53
3	39	26	30	22
Unclassified†	0	0	1	1
Margin Status					0.67
negative, ≥ 2 mm	133	89	121	88
negative, < 2 mm	16	11	17	12
Quadrant					0.28
Central	16	11	27	20
Lower Inner	9	6	7	5
Lower Outer	22	15	17	12
Upper Inner	22	15	15	11
Upper Outer	80	54	72	52
Estrogen Receptor Status					0.39
Positive	130	87	118	86
Negative	18	12	16	12
Not tested	1	1	4	3
Progesterone Receptor Status					0.42
Positive	112	75	102	74
Negative	36	24	32	23
Not tested	1	1	4	3
Her2-neu Status					0.43
Positive	12	8	11	8
Negative	102	69	103	75
Not tested	35	24	24	17
Pathologic Stage among patients with invasive cancer without neoadjuvant therapy (n=196)‡
pT1mic-pT1a	16	17	12	12	0.44
pT1b	24	26	23	23
pT1c	43	46	48	47
pT2	11	12	19	19
pN0	79	84	89	87	0.02
pN1mic	14	15	6	6
pN1a	1	1	7	7
Clinical and Pathologic Stage among patients with invasive cancer with neoadjuvant therapy (n=28)‡
cT1c	2	12	2	17	0.76
cT2	14	88	10	84
cN0	13	81	11	92	0.44
cN1a	3	19	1	8
pT0	7	44	5	42	0.68
pTis	1	6	2	17
pT1a	2	13	0	0
pT1b	0	0	0	0
pT1c	4	25	3	25
pT2	2	13	2	17
pN0	16	100	12	100	.
Treatment characteristics
Chemotherapy					0.67
None	106	71	96	70
Neoadjuvant	16	11	12	9
Adjuvant	27	18	30	22
Treatment Location					0.16
Houston-area	141	95	132	96
Banner MD Anderson	4	3	0	0
Orlando Health	4	3	6	4

Abbreviations: CF (conventionally fractionated), DCIS (ductal carcinoma in situ), HF (hypofractionated), WBI (whole breast irradiation)

^*Fisher’s exact test used for race, estrogen receptor status, progesterone receptor status, and bra cup size. Chi-square test used for all other comparisons.

^†This patient’s cancer was diagnosed on core biopsy but grade could not be assigned. There was no residual disease in the lumpectomy specimen.

^‡Staging information is only presented for patients with invasive breast cancer. A total of 63 patients had DCIS. Because DCIS typically does not undergo pathologic staging of the axillary nodes, patients with DCIS are not included in the comparison of stage by randomization arm. Additionally, staging is different for patients treated with upfront surgery compared to those treated with neoadjuvant chemotherapy, which is the reason that these two groups of patients are separated in the table.

ER positive: ≥ 1% of cells stained for estrogen receptor; PR positive: ≥ 1% of cells stained for progesterone receptor; Her2-neuNeu positive: 3+ by immunohistochemistry or gene amplification by fluorescence in situ hybridization