Table 3.

Comparison of patient characteristics according to the use of neoadjuvant chemotherapy before and after propensity score matching (PSM).

Characteristics	Unmatched cohort					1:1 propensity score matched (PSM) cohort
	Neoadjuvant+surgical		Chemotherapy alone		Unadjusted	Neoadjuvant+surgical		Chemotherapy alone		PSM-adjusted
	N = 825	%	N = 4,079	%	P value	N = 715	%	N = 715	%	P value
Age at diagnosis					< 0.001					0.562
< 40	152	18.42	368	9.02		112	15.66	122	17.06
40–49	188	22.79	625	15.32		164	22.94	147	20.56
50–59	236	28.61	1,186	29.08		207	28.95	213	29.79
60–69	169	20.48	1,162	28.49		155	21.68	150	20.98
70–79	67	8.12	553	13.56		64	8.95	61	8.53
80+	13	1.58	185	4.54		13	1.82	22	3.08
Months from diagnosis to therapy					0.001					0.601
0	296	35.88	1,724	42.27		266	37.20	269	37.62
≥1	526	63.76	2,322	56.93		446	62.38	445	62.24
Unknown	3	0.36	33	0.81		3	0.42	1	0.14
Subtype					< 0.001					0.688
HR+/HER2–	431	52.24	2,229	54.65		380	53.15	365	51.05
HR+/HER2+	196	23.76	740	18.14		169	23.64	161	22.52
HR–/HER2+	79	9.58	368	9.02		63	8.81	71	9.93
HR–/HER2–	95	11.52	402	9.86		80	11.19	95	13.29
Unknown	24	2.91	340	8.34		23	3.22	23	3.22
Race					0.137					0.161
White	619	75.03	2,998	73.50		538	75.24	525	73.43
Black	107	12.97	635	15.57		94	13.15	118	16.50
Other	99	12.00	446	10.93		83	11.61	72	10.07
Histological type					< 0.001					0.827
IDC	666	80.73	2,760	67.66		576	80.56	586	81.96
ILC	49	5.94	436	10.69		46	6.43	38	5.31
Mixed	56	6.79	201	4.93		45	6.29	43	6.01
Other	54	6.55	682	16.72		48	6.71	48	6.71
Marriage status					0.053					0.769
Married	514	62.30	1,891	46.36		352	49.23	343	47.97
Single	255	30.91	1,001	24.54		182	25.45	194	27.13
Others	263	31.88	1,187	29.10		181	25.31	178	24.90
T stage					< 0.001					0.958
T1	63	7.64	523	12.82		60	8.39	55	7.69
T2	238	28.85	1,076	26.38		206	28.81	203	28.39
T3	180	21.82	609	14.93		149	20.84	149	20.84
T4	325	39.39	1,343	32.92		281	39.30	285	39.86
Tx	19	2.30	528	12.94		19	2.66	23	3.22
N stage					< 0.001					0.664
N0	94	11.39	882	21.62		91	12.73	78	10.91
N1	377	45.70	1,984	48.64		344	48.11	339	47.41
N2	163	19.76	302	7.40		121	16.92	123	17.20
N3	187	22.67	736	18.04		155	21.68	168	23.50
Nx	4	0.48	175	4.29		4	0.56	7	0.98
Grade					< 0.001					0.885
Well	52	6.30	257	6.30		50	6.99	52	7.27
Moderately	319	38.67	1,345	32.97		290	40.56	275	38.46
Poorly	387	46.91	1,360	33.34		341	47.69	353	49.37
unknown	67	8.12	1,117	27.38		84	11.75	85	11.89
Median household income (inflation adjusted)					0.333					0.920
< 50,000$	94	11.39	483	11.84		77	10.77	77	10.77
50,000–59,999$	142	17.21	634	15.54		122	17.06	124	17.34
60,000–69,999$	286	34.67	1,345	32.97		254	35.52	242	33.85
70,000+	303	36.73	1,617	39.64		262	36.64	272	38.04
Radiotherapy					< 0.001					0.748
No/unknown	304	36.85	2,658	65.16		302	42.24	308	43.08
Yes	521	63.15	1,421	34.84		413	57.76	407	56.92
Liver metastases					< 0.001					0.883
No/unknown	713	86.42	2,776	68.06		606	84.76	604	84.48
Yes	112	13.58	1,303	31.94		109	15.24	111	15.52
Lung metastases					< 0.001					0.650
No/unknown	720	87.27	2,825	69.26		610	85.31	616	86.15
Yes	105	12.73	1,254	30.74		105	14.69	99	13.85
Brain metastases					< 0.001					0.429
No/unknown	814	98.67	3,699	90.68		704	98.46	700	97.90
Yes	11	1.33	380	9.32		11	1.54	15	2.10
Distant other metastases					< 0.001					0.759
No/unknown	802	97.21	3,724	91.30		694	97.06	692	96.78
Yes	23	2.79	355	8.70		21	2.94	23	3.22