Impact of Postmastectomy Radiotherapy on Locoregional Control and Disease-Free Survival in Patients with Breast Cancer Treated with Neoadjuvant Chemotherapy

Table 1

Clinical pathological characteristics of all patients (N = 554).

Variable	All		RT		No RT		value
	N = 554	%	N = 399	%	N = 155	%
Age (years)							0.980
<50	239	43.1	172	43.10	67	43.20
≥50	315	56.9	227	56.90	88	56.80
Menopausal status							0.609
Perimenopausal	255	46.0	184	46.11	71	45.81
Postmenopausal	265	47.8	193	48.37	72	46.45
Not known	34	6.1	22	5.51	12	7.74
Side of primary tumour							0.812
Left	294	53.1	213	53.38	81	52.26
Right	260	46.9	186	46.62	74	47.74
Tumour size, cm							≤0.001
<4	384	69.3	258	64.67	126	81.29
≥1	170	30.7	141	35.33	29	18.71
Tumour grade							0.445
G1-G2	274	49.5	194	48.62	80	51.61
G3	54	9.8	41	20.28	13	8.39
Not known	226	40.8	164	41.10	62	40
Histological type							0.449
Ductal	485	87.6	345	86.47	140	90.32
Tubular	30	5.4	24	6.02	6	3.87
Others	39	7.0	30	7.52	9	5.81
ER status							0.618
ER+	336	60.6	245	61.40	91	58.70
ER−	217	39.2	154	38.60	63	40.60
PR status							0.216
PR+	264	47.7	197	49.40	67	43.23
PR−	289	52.2	202	50.60	87	56.13
HER-2 status							0.447
HER-2 positive	114	20.6	85	21.30	29	18.71
HER-2 negative	378	68.2	268	67.20	110	80.00
Not recorded	62	11.2	46	11.50	16	10.30
TBC							0.020
Yes	98	17.7	61	15.30	37	23.90
No	394	71.1	292	73.20	102	65.80
Clinical T stage							≤0.001
T1-T2	438	79.1	297	74.44	141	90.97
T3-T4	116	20.9	102	25.57	14	9.03
Clinical N stage							≤0.001
N0	130	23.5	69	17.30	61	39.35
N1	339	61.2	260	65.16	79	50.97
N2	85	15.3	70	17.54	15	9.68
Clinical TNM stage							≤0.001
II	394	71.1	263	65.91	131	84.52
III	160	28.9	136	34.09	24	15.48
Clinical tumour response							0.415
CR + PR	472	85.2	343	85.96	129	83.23
SD + PD	82	14.8	56	14.04	26	16.77
Pathological response							≤0.001
pCR	38	6.9	15	3.76	23	14.84
No pCR	516	94.1	384	96.24	132	85.16
LVI							0.315
Yes	62	11.2	48	12.03	14	9.03
No	492	88.8	351	87.97	141	90.97
Pathological T stage							≤0.001
T0/tis	55	9.9	29	7.27	26	16.77
T1	279	50.4	199	49.87	80	51.61
T2–T4	220	39.7	171	42.86	49	31.61
Pathological N stage							≤0.001
N0	177	31.0	83	20.80	94	60.65
N1	192	34.7	152	38.10	40	25.81
N2-3	185	33.3	164	41.10	21	13.55
Pathological stage							≤0.001
0	38	6.9	15	3.76	23	14.84
I	94	16.0	44	11.03	50	32.26
II	228	41.2	168	42.11	60	38.71
III	194	35.0	172	43.11	22	14.19

PMRT, postmastectomy radiation therapy; ER, estrogen receptor; PR, progesterone receptor; HER-2, human epidermal growth factor receptor; TNBC, triple-negative breast cancer; pCR, pathological complete response; CR, complete response; PR, partial response; SD, stable disease; PD, progress disease; LVI, lymphatic vascular infiltration; HR, hazard ratio.