Table 2.

Patient demographic and clinical characteristics after propensity score matching.

Characteristics	IMPC (n = 324) n	%	IDC (n = 324) n	%	p value
Age, years					0.077
Mean	52.4		51.7
SDa	11.0		9.7
Tumour size, cm					0.370
T ≤ 2	130	40.1	126	38.9
2 < T ≤ 5	181	55.9	177	54.6
T ≥ 5	13	4.0	21	6.5
Node status					0.715
0	101	31.2	101	31.2
1–3	85	26.2	97	29.9
4–9	71	21.9	66	20.4
≥10	67	20.7	60	18.5
TNM stage					0.441
I	58	17.9	54	16.7
II	125	38.3	141	43.5
III	141	43.8	129	39.8
LVI b					0.869
yes	231	71.3	237	73.1
no	72	22.2	67	20.6
unknown	21	6.4	20	6.2
Hormone status
ERc positive	275	84.3	283	87.3	0.363
PRd positive	260	84.3	258	79.6	0.845
HER2e positive	107	33.0	100	30.9	0.555
Surgery					0.609
MRMf	249	76.8	263	81.2
BCSg	31	9.8	25	7.7
Mastectomy	28	8.6	23	7.1
Others	16	4.9	13	4.0

SD^a: standard deviation.

LVI^b: lymphovascular invasion.

ER^c: oestrogen receptor.

PR^d: progestin receptor.

HER2^e: epidermal growth factor receptor 2.

MRM^f: modified radical mastectomy.

BCS^g: breast conserving surgery.