Relationship between Clinicopathologic Variables in Breast Cancer Overall Survival Using Biogeography-Based Optimization Algorithm

Table 2

Univariate Cox regression analysis of clinicopathologic variables in breast cancer overall survival.

Variable	Comparison		Univariate
			HR	95% CI	p-value
Age	50 years	50 years	0.789	0.486-1.281	0.338
Grade	III	I, II	2.169	1.332-3.558	0.002
HER 2	Positive	Negative	1.036	0.638-1.683	0.887
Estrogen receptor	Positive	Negative	0.400	0.246-0.650	<0.001
Progesterone receptor	Positive	Negative	0.494	0.304-0.804	0.005
Tumor size (AJCC stage)	2.4 cm	2.4 cm	4.362	2.556-7.448	<0.001
Lymph node (AJCC stage)	Positive	Negative	2.689	1.631-4.434	<0.001
Lymphovascular invasion	Positive	Negative	2.960	1.825-4.801	<0.001
Dermal invasion	Positive	Negative	3.060	1.453-6.445	0.003
Perineural invasion	Yes	No	2.558	1.473-4.444	<0.001
Surgery method	Total mastectomy	Partial mastectomy	2.981	1.761-5.047	<0.001
Radiotherapy (RT)	Without RT	With RT	1.446	0.891-2.348	0.135
Chemotherapy (CT)	Without CT	With CT	0.782	0.438-1.397	0.406
Hormone therapy (HT)	Without HT	With HT	2.666	1.636-4.345	<0.001
Target therapy (TT)	Without TT	With TT	0.779	0.432-1.704	0.409

p-value is estimated using the Cox PH regression.
HR: hazard ratio; HER2: human epidermal growth factor receptor 2.