TABLE 2.

Predictors of conversion to BCS-eligibility with NAC

Characteristic	Overall n = 600	Post-NAC BCS candidate		Univariable	Multivariable
		No n = 150	Yes n = 450	p value	Odds ratio	95% Cl	p value
Age at diagnosis, median, years (range)	49 (25,87)	49 (27,87)	49 (25,82)	0.3	--	--
Clinical tumor size, median, cm (range)#	4.0 cm (0.9,12)	5.0 cm (0.9,12)	4.0 cm (1.0,12)	<0.001	0.86	0.78–0.95	0.003
Pre-NAC BCS candidate				<0.001			0.003
Borderline	188	24 (13%)	164 (87%)		Ref
No	412	126 (31%)	286 (69%)		0.46	0.27–0.76
Clinical T stage				<0.001	--	--
T1	37	8 (22%)	29 (78%)
T2	393	81 (21%)	312(79%)
T3	170	61 (36%)	109 (64%)
Clinical nodal status				<0.001			0.008
cN0	225	36 (16%)	189 (84%)		Ref
cN+	375	114(30%)	261 (70%)		0.54	0.34–0.84
Pre-NAC calcifications				<0.001			0.007
No	413	83 (20%)	330 (80%)		Ref
Yes	187	67 (36%)	120 (64%)		0.56	0.36–0.85
Receptor Status				<0.001
HR+/HER2−	196	74 (38%)	122 (62%)		Ref
HER2+	227	47 (21%)	180 (79%)		1.63	1.01–2.65	0.047
HR-/HER2−	177	29 (16%)	148 (84%)		2.26	1.33–3.91	0.003
Differentiation				0.009	--	--
Well	7	4 (57%)	3 (43%)
Moderate	141	45 (32%)	96 (68%)
Poor	452	101 (22%)	351 (78%)
Histology§				0.015	--	--
Ductal	554	130 (23%)	424 (77%)
Lobular	20	9 (45%)	11 (55%)
Mixed	19	9 (47%)	10 (53%)
Other*	6	2(33)	4 (67%)
Breast pCR				<0.001			<0.001
No	433	129 (30%)	304 (70%)		Ref
Yes	167	21 (13%)	146 (87%)		2.62	1.54–4.66

BCS breast-conserving surgery, NAC neoadjuvant chemotherapy, CI confidence interval, HR hormone receptor, HER2 human epidermal growth factor receptor 2, pCR pathologic complete response

^#Unknown (tumor size), n = 16

^§Unknown (histology) n = 1

^*other = 4 metaplastic, 1 anaplastic, 1 mucinous