Table 1.

Patients’ characteristics and univariate analysis of factors related to survival

Factor	Cases	%	Events	%	p value*	HR	95% CI**
Age					.012
Up to 35 years old	47	5.24	16	34.04		1.63	0.98–2.73
36-69 years old	677	75.47	159	23.49		1.00
70 and older	173	19.29	53	30.64		1.50	1.10–2.04
Tumor size					< 0.001
T1 (up to 2 cm)	319	35.56	33	10.34		1.00
T2 (2–5 cm)	348	38.80	88	25.29		2.59	1.73–3.86
T3	105	11.71	37	35.24		4.03	2.52–6.45
T4	125	13.94	70	56.00		8.02	5.29–12.16
Lymph node status					< 0.001
N0	387	43.14	45	11.63		1.00
N1	255	28.43	67	26.27		2.56	1.76–3.74
N2	155	17.28	68	43.87		4.83	3.31–7.04
N3	100	11.15	48	48.00		5.25	3.50–7.90
Stage					< 0.001
I	223	24.86	13	5.83		1.00
II	315	35.12	58	18.41		3.34	1.83–6.10
III	359	40.02	157	43.73		9.84	5.58–17.33
Bilateral breast cancer					0.380
Yes	29	3.23	10	34.48		1.33	0.70–2.50
No	868	96.77	218	25.12		1.00
Histologic grade					< 0.001
Grade 1	181	20.18	23	12.71		1.00
Grade 2	385	42.92	77	20.00		1.71	1.07–2.72
Grade 3	320	35.67	124	38.75		3.72	2.38–5.80
Unknown	11	1.23	4	36.36
Pathology		0.00			.449
Invasive ductal carcinoma	760	84.73	199	26.18		1.00
Invasive lobular carcinoma	79	8.81	15	18.99		0.73	0.43–1.23
Other	58	6.47	14	24.14		0.86	0.50–1.48
Public health system					0.006
Yes	823	91.75	216	26.25		2.22	1.24–3.98
No	74	8.25	12	16.22		1.00
Neoadjuvant therapy					<0.001
Yes	166	18.51	77	46.39		2.87	2.18–3.78
No	731	81.49	151	20.66		1.00
Axillary node dissection					<0.001
Yes	684	76.25	211	30.85		3.82	2.33–6.27
No	213	23.75	17	7.98		1.00
Type of surgery					<0.001
Mastectomy	537	59.87	182	33.89		2.89	2.09–4.00
Breast-conserving surgery	360	40.13	46	12.78		1.00

*Log-rank test.

**95% Confidence interval.