Table 1. Patient and Tumor Characteristics by Age Group.

*p<0.01;

a=Chi-Square Test; Mann-Whitney U Test, MC/MF - Multicentricity/multifocality, IDC - Invasive ductal carcinoma, LVI - Lymphovascular invasion.

	Age <35  (n=125)		Age 35–40  (n=207)
	n	%	n	%	Total		pa
Breast surgery type
BCS	82	65.6	131	63.3	213	64.2	0.670
Mastectomy	43	34.4	76	36.7	119	35.8
pT Stage
1	66	52.8	107	51.7	173	52.1	0.845
2-3	59	47.2	100	48.3	159	47.9
pN Stage
pN0	61	48.8	109	52.7	170	51.2	0.496
pN1-3	64	51.2	98	47.3	162	48.8
p Stage (TNM)
1	42	33.6	72	34.8	114	34.3	0.826
2-3	83	66.4	135	65.2	218	65.7
Histology
IDC	110	88.0	179	86.5	289	87.0	0.688
Others	15	12.0	28	13.5	43	13.0
Tumor focality
Unifocal	103	82.4	142	68.6	245	73.8	0.006*
MC/MF	22	17.6	65	31.4	87	26.2
Histological grade
I-II	58	46.4	110	53.1	168	50.6	0.234
III	67	53.6	97	46.9	164	49.4
LVI
Positive	67	54.5	110	53.4	177	53.8	0.850
Negative	56	45.5	96	46.6	152	46.2
In situ component (n=328)
Positive	87	70.7	145	70.7	232	70.7	1.000
Negative	36	29.3	60	29.3	96	29.3
ER
Negative	36	28.8	53	25.6	89	26.8	0.524
Positive	89	71.2	154	74.4	243	73.2
PR
Negative	86	68.8	145	70.0	231	69.6	0.811
Positive	39	31.2	62	30.0	101	30.4
Her-2 (n=328)
Negative	94	76.4	143	69.8	237	72.3	0.192
Positive	29	23.6	62	30.2	91	27.7
Chemotherapy
Received	116	92.8	178	86.0	294	88.6	0.087
Non- Received	9	7.2	29	14.0	38	11.4
Hormonal therapy
Received	95	76.0	161	77.8	256	77.1	0.709
Non-Received	30	24.0	46	22.2	76	22.9
Median Tm diameter	20	(2-110)	20	(1-110)	20	(1-110)	0.494
Median Ki-67 %	25	(5-85)	30	(2-95)	30	(2-95)	0.390